NationStates Jolt Archive

I was watching a vid. today about how the evolution of animals and crap, and i never got why sea creatures made the jump to land animals. Can someone explain this to me? I understand that evolution occurs as to adapt to enviromental changes and such. But, if sea creatures never had the ability to survive out of water, then how would they have supposedly adapt to to such a state? I was just wondering how they made that jump from sea to land. :confused: :confused: :confused:

Short answer:

We don't know, but there are theories.

Well, it wasn't like one single mutant suddenly jumped out of the sea and lived his life on land. Amphibians, man. Mutations occured slowly that wound up enabling partial life out of water. And later, with reptiles, from partial to total.

A pond dries up in the dry season, hundreds of fish suffocate in the shrinking water. Some fish tried to flop or roll their way to another pool of water with the interest of self-preservation, mudkippers are a modern example of this.

The first land animals were probably like mud skippers or

>.>

<.<

snakehead fish...

Ocean-dwelling animal evolves into amphibian, amphibian evolves into reptile, etc... is what I've always thought had happened. Doesn't explain mammals or birds, but it kind of makes sense when considered by itself.

Well, it wasn't like one single mutant suddenly jumped out of the sea and lived his life on land. Amphibians, man. Mutations occured slowly that wound up enabling partial life out of water. And later, with reptiles, from partial to total.

I thought that, but, it still seems odd to me. I don't know why. Like I am fine with everything else before and after this point. Its just this one point that messes with me.

The first land animals were probably like mud skippers or

>.>

<.<

snakehead fish...


don't forget lungfish

A pond dries up in the dry season, hundreds of fish suffocate in the shrinking water. Some fish tried to flop or roll their way to another pool of water with the interest of self-preservation, mudkippers are a modern example of this.

yes, but wouldn't they die, those first ones that is, because they are out of water, and didn't previously have the tools to survive?

Room was probably an issue. Things get crowded in the water but just past the shore is a lot of wide open space to settle. Sure it's a little different and a little less friendly what with the oxygen burning gills and skin but you just can't say no to all that room and low competition.

As for the ponds drying up, some species adapted legs and feet before they left the water so they could move around on the bottom in the shallows and through thick weedy vegetation. In short, some took a different approach and it seems to have paid off.

don't forget lungfish

*nod* Them too...

Damn, I just lost The Game...

yes, but wouldn't they die, those first ones that is, because they are out of water, and didn't previously have the tools to survive?

say the drying up pond is 10-15 feet fom a flowing river, or they might have used mud to stay moist and small pools of water in this mud would act like air pockets.

EDIT: this is all idle speculation...we may never know..

I thought that, but, it still seems odd to me. I don't know why. Like I am fine with everything else before and after this point. Its just this one point that messes with me.

Look at it this way--for whatever reason, there was a biological advantage to being able to live on land at least part-time. That eventually evolved into an advantage to living on land full-time. Anytime there's a biological advantage to doing something in a particular way, there will usually be an organism that will evolve to fit that niche, and it will procreate and survive because it fits that niche, and if that niche disappears, the animal will either evolve, or it will disappear.

say the drying up pond is 10-15 feet fom a flowing river, or they might have used mud to stay moist and small pools of water in this mud would act like air pockets.

EDIT: this is all idle speculation...we may never know..

Room was probably an issue. Things get crowded in the water but just past the shore is a lot of wide open space to settle. Sure it's a little different and a little less friendly what with the oxygen burning gills and skin but you just can't say no to all that room and low competition.

As for the ponds drying up, some species adapted legs and feet before they left the water so they could move around on the bottom in the shallows and through thick weedy vegetation. In short, some took a different approach and it seems to have paid off.

Look at it this way--for whatever reason, there was a biological advantage to being able to live on land at least part-time. That eventually evolved into an advantage to living on land full-time. Anytime there's a biological advantage to doing something in a particular way, there will usually be an organism that will evolve to fit that niche, and it will procreate and survive because it fits that niche, and if that niche disappears, the animal will either evolve, or it will disappear.



oooooo....Ok...it makes a lot more sense now. Thank ye!

I was watching a vid. today about how the evolution of animals and crap.

So, if you leave it in the bowl long enough it will turn into a fish or something? I'd like to check that out but I'm afraid if I left a floater in there that long it would really stink. How long does it take crap to evolve? Also, if only animals crap, how did the first crap evolve? :confused:

yes, but wouldn't they die, those first ones that is, because they are out of water, and didn't previously have the tools to survive?

They don't live out of water full time, at least at first. It probably originated as merely short jumps to get between pools, or catch bugs, or stuff like that.

oooooo....Ok...it makes a lot more sense now. Thank ye!

the evolution picture showing a fish swimming close to a beach then magically sprouting perfect legs don't help much, do they?

oooooo....Ok...it makes a lot more sense now. Thank ye!

Glad to be of service.

I thought that, but, it still seems odd to me. I don't know why. Like I am fine with everything else before and after this point. Its just this one point that messes with me.

Eels can travel up to 30 miles over land (in case you don't want to take my word for it (http://en.wikipedia.org/wiki/Eel_life_history)), Snakeheads (http://en.wikipedia.org/wiki/Snakehead_fish) have developed primitive lungs, and I remember reading about a species of fish in Asia that are currently evolving into an amphibian life form, being capable not only of leaving the sea but to actually climb trees. I can't remember what they are called, but I'm trying to find information on them...

Eels can travel up to 30 miles over land (in case you don't want to take my word for it (http://en.wikipedia.org/wiki/Eel_life_history)), Snakeheads (http://en.wikipedia.org/wiki/Snakehead_fish) have developed primitive lungs, and I remember reading about a species of fish in Asia that are currently evolving into an amphibian life form, being capable not only of leaving the sea but to actually climb trees. I can't remember what they are called, but I'm trying to find information on them...

mudskippers.http://www.aquascape.co.uk/mudskipper.jpg

I thought that, but, it still seems odd to me. I don't know why. Like I am fine with everything else before and after this point. Its just this one point that messes with me.

Probably because the differences between aquatic and land animals are so well known and pronounced, the conceptual bridging of the two is hard to grasp, especially since evolution is something kind of difficult to conceptualize anyway.

Also, you do know that typing "non debate" in the title was an invitation to all the NSG debaters who are now gonna start debating, yes? ;)

the evolution picture showing a fish swimming close to a beach then magically sprouting perfect legs don't help much, do they?

exactly. I was watching this vid in an university setting too :\

I was watching a vid. today about how the evolution of animals and crap, and i never got why sea creatures made the jump to land animals. Can someone explain this to me? I understand that evolution occurs as to adapt to enviromental changes and such. But, if sea creatures never had the ability to survive out of water, then how would they have supposedly adapt to to such a state? I was just wondering how they made that jump from sea to land. :confused: :confused: :confused:


Look at it this way. At the shore there are plants that are completly adapted to living in the water, but will, accidentally, wash up on the shore. For hours and hours every day theres a feast of plant matter waiting for the daring fish who can come and eat it first. There would already be fish well adapted to using strong front flippers to dig in the shorline silt, so then some of them would be first to eat when the tide started to go in.

Eventually other advantages would become available to those who can get out the earliest and go back the latest. Fewer predators for one thing. Much like why goats live in the mountains instead of the plains. This eventually leads to "fish" that never need to go back. They get to keep eating without having to compete with the bigger stronger fish back in the water. But eventually they must compete with each other, leading to the diversity of land animals we have today (or even greater diversity in previous ages.)

Eels can travel up to 30 miles over land (in case you don't want to take my word for it (http://en.wikipedia.org/wiki/Eel_life_history)), Snakeheads (http://en.wikipedia.org/wiki/Snakehead_fish) have developed primitive lungs, and I remember reading about a species of fish in Asia that are currently evolving into an amphibian life form, being capable not only of leaving the sea but to actually climb trees. I can't remember what they are called, but I'm trying to find information on them...

There's also a fish in Africa called the 'lungfish' that adapts to the dry season by slithering from mudhole to mudhole until eventually hibernating through the dry season.

snippy But eventually they must compete with each other, leading to the diversity of land animals we have today (or even greater diversity in previous ages.)
Really? Animal diversity used to be greater?

So, if you leave it in the bowl long enough it will turn into a fish or something? I'd like to check that out but I'm afraid if I left a floater in there that long it would really stink. How long does it take crap to evolve? Also, if only animals crap, how did the first crap evolve? :confused:

:D

The earliest crap was simple sugars and alcohols. Later came oxegen. Just like plants live on modern crap, new single celled organisms lived on this primative crap, in turn producing new, more complicated forms of crap like amonia and nitrogen compounds.

Really? Animal diversity used to be greater?

Is that a sarcastic question?

Yes. Diversityused to be greater. Some animals have gone extinct in the last few centuries. Before those extinctions animal diversity was, by definition, greater.

Is that a sarcastic question?
Nope... not really...

Yes. Diversityused to be greater. Some animals have gone extinct in the last few centuries. Before those extinctions animal diversity was, by definition, greater.
:rolleyes:
I thought you meant animal diversity was greater by a significant margin.

:D

The earliest crap was simple sugars and alcohols. Later came oxegen. Just like plants live on modern crap, new single celled organisms lived on this primative crap, in turn producing new, more complicated forms of crap like amonia and nitrogen compounds.

Oh. Too bad crap evolved that way. Early crap sounds like it smelled wonderfull! :) Crap stinks, now.

I was watching a vid. today about how the evolution of animals and crap, and i never got why sea creatures made the jump to land animals. Can someone explain this to me? I understand that evolution occurs as to adapt to enviromental changes and such. But, if sea creatures never had the ability to survive out of water, then how would they have supposedly adapt to to such a state? I was just wondering how they made that jump from sea to land. :confused: :confused: :confused:

Don't attack it from the back.

There was no 'goal'. There wasn't a straight-line of evolution that heads straight from marine-to-landlubber.

Evolution relies on the idea of small changes, over periods of time... and environment.


Example - fish x is one of millions... but fish x has a faulty swim-bladder. It 'leaks'. Just a bit. Fish x is very slightly less bouyant than his ancestors... but he swims just a little harder, and compensates. It doesn't really harm fish x, so his line doesn't die out.

Maybe millions of years later, the great descendents of fish x all have faulty swim-bladders. The 'problem' has been magnified, by millions of years of breeding.

(In some of the line, the breeding was 'outside' of the bloodline... those fish have almost un-noticable swim-bladder deficiency... but they MAY have introduced a weakness into the collective genepool.)

Some of the fish of this line may have been more isolated. In them, there was less outside breeding, so the condition is exacerbated. Fortunately, their isolated environment is teeming with food, so they have survived anyway... despite this 'broken' swim-bladder.


Some time later, there is an environment change on a small or large scale. The 'linebreeding' descendents of fish x are just one of millions of 'types' fighting for survival in this new environment.

Maybe it's been warm for a few years... The fresh-water all these fish were living in is drying up... the water is much more shallow than before. Some fish don't have enough water to breed... many are finding it hard to get enough oxygen out of the silty shallow water.

Except the 'fish x' line. For some reason, they seem to be thriving. It seems that 'broken' swim-bladder that leaks... can function as a kind of 'gas exchanger'... a kind of very basic 'lung'... allowing the shallow-dwelling fish to 'breathe' at the surface... and even survive for short periods when the water level is so low it is little more than unbreathable mud....

Fast forward another million years...

I was watching a vid. today about how the evolution of animals and crap, and i never got why sea creatures made the jump to land animals. Can someone explain this to me?

which time?

evolution can be very slow or very quick depending circumstances.

Mutations occur at regular intervals, so evolution is alwasys taking place but it can be difficult to detect. An organism evolving from total aquatic to air breathing would likely take quite a long time. The examples of lungfish is good, but between lungfish and total water dweller would still be many tiny developmental steps.

Evolution can also seemingly go backwards-whales were originally land mammals that evolved into sea creatures, maybe in several million years they could develop gills or even return to the land.

Is that a sarcastic question?

Yes. Diversityused to be greater. Some animals have gone extinct in the last few centuries. Before those extinctions animal diversity was, by definition, greater.Yeah, but it's not like evolution has stopped either. New species are developing even as we speak, replacing those that have gone extinct.

Yeah, but it's not like evolution has stopped either. New species are developing even as we speak, replacing those that have gone extinct.

Well, it works like this.

You get an event that creates a lot of extinction, or just a blank slate in which animals can evolve.

Without much pressure to adapt, you get all sorts of wierd, badly adapted animals, like 8 foot gunea pigs. Then as populations explode, you get competative pressure and the 8 foot gunea pigs go extinct. As the predators run out of fat, slow, weak prey they have to specialize. Do the big cats want to be fast, strong, stealthy, or cooperative. They can't be all of them. So a generic sort of big cat becomes leopards, cheetahs, and lions. But all sorts of animals that are almost as fast as cheetahs, but not strong enough to make up for being slower, or less strong that tigers, but not stealthy enough to make up for the weakness die out. As well as smaller types of buffalo, or less prolific types of wildebeast.

New animals evolve, but it's usually not really to replace the ones that just died. The ones that used to exist were becoming the kind that survived and the kind that didn't.

There did used to be a greater diversity of animals before humans came along, but a lot of it was lost to increasing competition before humans came along.

I was watching a vid. today about how the evolution of animals and crap, and i never got why sea creatures made the jump to land animals. Can someone explain this to me? I understand that evolution occurs as to adapt to enviromental changes and such. But, if sea creatures never had the ability to survive out of water, then how would they have supposedly adapt to to such a state? I was just wondering how they made that jump from sea to land. :confused: :confused: :confused:

They were probably animals living near the surface. They probably made occasional jumps out of the water, thereby getting used to the outside air. Eventually they become able to breath outside-of-water air. When their genes realized this, they probably said "Hey! Let's adapt to the outside world!" Then another gene probably said "Yeah... But how do we get onto land?" Then the other gene probably said "Legs!". And after a while of genes deciding "LEGS!", eventually legs grew on fish. And the fishies came out of the water. EDIT: That's just my theory. And my theory put into radical silliness.

Entry onto dry land predated flying critters, according to accepted science, so living on land is an advantage as it eliminates the degrees of freedom at which preditators may get at you to 2 dimensions rather than 3.

You spend less energy watching for attackers, and more eating and mating, making dry land living an advantage.

They were probably animals living near the surface. They probably made occasional jumps out of the water, thereby getting used to the outside air. Eventually they become able to breath outside-of-water air. When their genes realized this, they probably said "Hey! Let's adapt to the outside world!" Then another gene probably said "Yeah... But how do we get onto land?" Then the other gene probably said "Legs!". And after a while of genes deciding "LEGS!", eventually legs grew on fish. And the fishies came out of the water. EDIT: That's just my theory. And my theory put into radical silliness.

Kage leg bunshin no jutsu?

Entry onto dry land predated flying critters, according to accepted science, so living on land is an advantage as it eliminates the degrees of freedom at which preditators may get at you to 2 dimensions rather than 3.
Doesn't that also limit your angles of escape, though?

Damn, I just lost The Game...
Bastard!

Kage leg bunshin no jutsu?

What?

Bastard!

:D And the cycle continues.

What?

Yanno, the genes make the hand signs then shout "LEGS!" and multiple legs appear.

Doesn't that also limit your angles of escape, though?

Well initially there would be no pradators on land, so there would be nothing to escape from. Essentially, everything that lived on land was born having already escaped from all known predators. That's why flight had to evolve later when predation became a problem for land dwellers.

Yanno, the genes make the hand signs then shout "LEGS!" and multiple legs appear.
Is Yanno a god or something? :confused:
Well initially there would be no pradators on land, so there would be nothing to escape from. Essentially, everything that lived on land was born having already escaped from all known predators. That's why flight had to evolve later when predation became a problem for land dwellers.

Oh *nod* That makes sense.

And after flight developed, flyers like the Peregrine would evolve to fill the newly created niche...

as far as how that could have been possible physiologically, it's actually quite simple: being submersed in water isn't necissary to breath with gills, only that there's enough oxygen-ladened water on the gills themselves.

guys like mudskippers, snakehead fish, etc., they still need a thin film of water on them to diffuse oxygen from the air - otherwise they'll suffocate in short order.

that's why the next step was reptiles/scales evolutionary theory claims (i'm almost certain amphibians are considered more recent than reptiles - and possibly even mammals! mitocondrial DNA evidence is what that idea is largely based on, if memory serves me correct)

Is Yanno a god or something? :confused:

I knew a deity once, but he asploded.

Yanno, the genes make the hand signs then shout "LEGS!" and multiple legs appear.

I was just being silly. What the genes are essentially thinking is that the best way to get to this new oxygen source is to get onto land. And how do you get onto land? "LEGS!"

I knew a deity once, but he asploded.

:eek:
That must have made a mess.

snippity snip snip

Exactly what I wanted to say, except more detailed and well-thought out.

The random genetic changes that occur, like a leaky swim bladder, can sometime turn out to be good (which would lead to more and more having it until it was an evolutionary trait) or bad (in which those with it die out).

The little things lead to evolution. A change here or there, not, as a few fundie preachers say, a man was born of a monkey somewhere.

:eek:
That must have made a mess.


You're livin' in it.

I was just being silly. What the genes are essentially thinking is that the best way to get to this new oxygen source is to get onto land. And how do you get onto land? "LEGS!"

it woulda been nice if the Motorized Scooter gene had spoken up first :D

I was just being silly. What the genes are essentially thinking is that the best way to get to this new oxygen source is to get onto land. And how do you get onto land? "LEGS!"

Evolution doesn't work like that.

Exactly what I wanted to say, except more detailed and well-thought out.

The random genetic changes that occur, like a leaky swim bladder, can sometime turn out to be good (which would lead to more and more having it until it was an evolutionary trait) or bad (in which those with it die out).

The little things lead to evolution. A change here or there, not, as a few fundie preachers say, a man was born of a monkey somewhere.

A rational approach to evolution, as opposed to what I call the 'Fish-into-bananas' version.

That name arises, by the way, after I honestly encountered a Christian who based their whole case for opposition to the idea of evolution, on the simple question: "If evolution existed, why doesn't a fish ever turn into a banana"?

You're livin' in it.

I was wondering what that smell was.

Evolution doesn't work like that.

*COUGH*"justbeingsilly"*COUGH-COUGH*

Evolution doesn't work like that.

It's called "adaptation". Fish decide to live near the surface. Fish occasionally jump out of water. Fish learn to breath outside of water. Fish like breathing outside of water. Fish want to stay outside water. Fish realize to stay out of water, you need legs. Fish develop legs.

It's called "adaptation". Fish decide to live near the surface. Fish occasionally jump out of water. Fish learn to breath outside of water. Fish like breathing outside of water. Fish want to stay outside water. Fish realize to stay out of water, you need legs. Fish develop legs.

And go-carts. That's like seven steps after developing legs.

it woulda been nice if the Motorized Scooter gene had spoken up first :D

Fish on scooters. Ha.

And go-carts. That's like seven steps after developing legs.

Fish on go-carts. Ha.

It's called "adaptation". Fish decide to live near the surface. Fish occasionally jump out of water. Fish learn to breath outside of water. Fish like breathing outside of water. Fish want to stay outside water. Fish realize to stay out of water, you need legs. Fish develop legs.

lol, i kinda feel bad about jibbing ifreann for saying "evolution doesn't work that way"!

okay... first off, they don't "learn" to breath air, etc. that theory was proposed nearly two hundred years ago and has long-since been debunked (e.g. a girraffe has such a long neck because he streched harder to reach more leaves, so his kids automatically had long necks)

also... snakes don't have legs, eh? :D

And go-carts. That's like seven steps after developing legs.

if that fish ever came to be, i'd TOTALLY call it Devaronius kevinbaconus :D :D :D

[EDIT] or maybe Mariokartus kevinbaconus...

Fish on scooters. Ha.



Fish on go-carts. Ha.

I don't believe in the scooter theory. The Go-Cart theory has much more evidence to be found in the fossil record. Scooters also do not explain the ancient Go-Cart Tracks to be found in Africa and parts of Europe and Asia.

lol, i kinda feel bad about jibbing ifreann for saying "evolution doesn't work that way"!

okay... first off, they don't "learn" to breath air, etc. that theory was proposed nearly two hundred years ago and has long-since been debunked (e.g. a girraffe has such a long neck because he streched harder to reach more leaves, so his kids automatically had long necks)

also... snakes don't have legs, eh? :D

Meh. I don't know how to say this without seeming like I totally disagree with you and want to start an arguement, but I want to know who it was who proposed it and who debunked it and how.

I don't believe in the scooter theory. The Go-Cart theory has much more evidence to be found in the fossil record. Scooters also do not explain the ancient Go-Cart Tracks to be found in Africa and parts of Europe and Asia.

"what if two scooters were riding together?!"

Meh. I don't know how to say this without seeming like I totally disagree with you and want to start an arguement, but I want to know who it was who proposed it and who debunked it and how.

gimme a sec, looking it up right now...

lol, i kinda feel bad about jibbing ifreann for saying "evolution doesn't work that way"!

okay... first off, they don't "learn" to breath air, etc. that theory was proposed nearly two hundred years ago and has long-since been debunked (e.g. a girraffe has such a long neck because he streched harder to reach more leaves, so his kids automatically had long necks)

also... snakes don't have legs, eh? :D
some snakes still have remnents of legs...Giraffes-if a giraffe ancestor had an abnormally long neck it's offspring would have greater chance of survival as it would reach food other animals could not. In times of severe shortage of food chances are that the taller giraffes and their offspring would survive, evolution by adaptation.

It's called "adaptation". Fish decide to live near the surface. Fish occasionally jump out of water. Fish learn to breath outside of water. Fish like breathing outside of water. Fish want to stay outside water. Fish realize to stay out of water, you need legs. Fish develop legs.

I'll let Morbo field this one:
http://tfp.killbots.com/scans/168_morbo-couch.gif
Evolution does not work like that!

Thank you Morbo.

Fish can't 'learn' to breathe out of water anymore that you could 'learn' to live in a pure chlorine gas enviroment. A random gene mutation allowed some fish to survive out of water temporarily(or permanently, we'll never know). The important word to note there is 'random'. Those fish could eat the plants on the shore and escape predators, thus they would be succesfful and have offspring, who would also carry those genes, and they too would thrive and so on.

Meh. I don't know how to say this without seeming like I totally disagree with you and want to start an arguement, but I want to know who it was who proposed it and who debunked it and how.
got it!

in the early 1800's a french naturalist Jean Baptiste de Lamarck (1744-1829) proposed new or evolved structures in an orgamism appear because of a need or "inner want." the giraffe example i mentioned is the most famous one (he also suggested snakes were lizards that had a "strong preference" for slithering ont eh ground - you can see why that one's not mentioned as much :D ).

as for the disproving... first, it's impossible via experimentation to prove that "inner want". also, aquired traits aren't automatically passed on to kids (think suntans, or the ability to ride a bike). the kicker, though, had to do with all that wonderful knowledge we gathered about genetics (i.e., that's how physical traits are actually passed down from generation to generation).

i'm not sure when it was disregarded by the majority, but it was questioned almost immediately. hope that helped!

I'll let Morbo field this one:
http://tfp.killbots.com/scans/168_morbo-couch.gif
Evolution does not work like that!

Thank you Morbo.

Fish can't 'learn' to breathe out of water anymore that you could 'learn' to live in a pure chlorine gas enviroment. A random gene mutation allowed some fish to survive out of water temporarily(or permanently, we'll never know). The important word to note there is 'random'. Those fish could eat the plants on the shore and escape predators, thus they would be succesfful and have offspring, who would also carry those genes, and they too would thrive and so on.

So evolution is completely random? So for some reason, birds decided to grow wings? Not to escape predators? Just for the sake of growing wings? And it is impossible for humanity, over several generations I note, to evolve to be able to survive in harsher, winter enviroments, where the air is thinner?

some snakes still have remnents of legs...Giraffes-if a giraffe ancestor had an abnormally long neck it's offspring would have greater chance of survival as it would reach food other animals could not. In times of severe shortage of food chances are that the taller giraffes and their offspring would survive, evolution by adaptation.

yes, but the giraffe didn't stretch his own neck. that's the kicker. what you're talking about is natural selection/genetics, which is the modern, accepted theory

"what if two scooters were riding together?!"

One scooter should ride on the other. When you ride alone, you ride with Bin Laden.

got it!

in the early 1800's a french naturalist Jean Baptiste de Lamarck (1744-1829) proposed new or evolved structures in an orgamism appear because of a need or "inner want." the giraffe example i mentioned is the most famous one (he also suggested snakes were lizards that had a "strong preference" for slithering ont eh ground - you can see why that one's not mentioned as much :D ).

as for the disproving... first, it's impossible via experimentation to prove that "inner want". also, aquired traits aren't automatically passed on to kids (think suntans, or the ability to ride a bike). the kicker, though, had to do with all that wonderful knowledge we gathered about genetics (i.e., that's how physical traits are actually passed down from generation to generation).

i'm not sure when it was disregarded by the majority, but it was questioned almost immediately. hope that helped!

Hmm... So just because there's no experiment that is able to be performed, something is automatically untrue? That's what they are pretty much saying. And I think if a family of fish lived near the surface continually, and continually popped up out of the surface, I think the genes would eventually get passed down.

So evolution is completely random? So for some reason, birds decided to grow wings? Not to escape predators? Just for the sake of growing wings? And it is impossible for humanity, over several generations I note, to evolve to be able to survive in harsher, winter enviroments, where the air is thinner?

No, gene mutation is random. Then natural selection takes over. If the mutation allows the organism to survive and breed, it will be passed on(birds flying, for example. If they can escape predators and fly to new food sources they'll live long enough to breed). If the mutation puts the organism at a disadvantage then the organism won't live long enough to breed or won't be seen as a suitable mate(peacocks, for example, attract mates with their brightly coloured plumage. If a peacock was born with one or more genes mutated in such a way that his plumage was less impressive, he would likely not get a mate and the mutation would not be passed on).

A rational approach to evolution, as opposed to what I call the 'Fish-into-bananas' version.

That name arises, by the way, after I honestly encountered a Christian who based their whole case for opposition to the idea of evolution, on the simple question: "If evolution existed, why doesn't a fish ever turn into a banana"?

Jesus H. Christ.

Wait, that's even more ironically stupid! :p

Hmm... So just because there's no experiment that is able to be performed, something is automatically untrue? That's what they are pretty much saying. And I think if a family of fish lived near the surface continually, and continually popped up out of the surface, I think the genes would eventually get passed down.

Living near the surface of the water would not cause a fish's genes to mutate to allow them to live on land.

So evolution is completely random? So for some reason, birds decided to grow wings? Not to escape predators? Just for the sake of growing wings? And it is impossible for humanity, over several generations I note, to evolve to be able to survive in harsher, winter enviroments, where the air is thinner?

genetic mutation is random, yes. but there's no gene for "wing" or "leg" or "elephant trunk". the way you're wording it, it's like the birds put concious effort into adjusting their DNA to develope wings.

remeber, evolution is said to be gradual - it's extremely slow in the making. there wasn't an animal with no legs, then five generations later it's got em.

as for the human evolution: there actually ARE peoples that are better adapted to living in high altitudes (see also: Andes Indians). could humans change into something vastly different? who knows... but if natural selection in humans were to truely take place, things like social welfare and society would have to be either eliminated or greatly reduced - "only the strongest survive" won't happen with everyone getting food (which isn't the case now of course, i know :-P)

p.s. i'm NOT suggesting we let all poor people starve or anything ludicrous like that! i was merely saying that, from a truely natural and emotionally-removed perspective, humans are slightly hindering their physiological evolutionary process.

again, i'm neither a "Master Race", nor eugenics enthusiast :rolleyes:

No, gene mutation is random. Then natural selection takes over. If the mutation allows the organism to survive and breed, it will be passed on(birds flying, for example. If they can escape predators and fly to new food sources they'll live long enough to breed). If the mutation puts the organism at a disadvantage then the organism won't live long enough to breed or won't be seen as a suitable mate(peacocks, for example, attract mates with their brightly coloured plumage. If a peacock was born with one or more genes mutated in such a way that his plumage was less impressive, he would likely not get a mate and the mutation would not be passed on).

Well I think most fish swimed to the surface to escape predators, most of which (during that time) were deep underwater. So I think the fish (who were probably essentially living on the surface) probably lived. And if you're going to ask what they ate, remeber algae?

Living near the surface of the water would not cause a fish's genes to mutate to allow them to live on land.

No, but the want to be able to constantly breath the air on the surface will.

genetic mutation is random, yes. but there's no gene for "wing" or "leg" or "elephant trunk". the way you're wording it, it's like the birds put concious effort into adjusting their DNA to develope wings.

remeber, evolution is said to be gradual - it's extremely slow in the making. there wasn't an animal with no legs, then five generations later it's got em.

as for the human evolution: there actually ARE peoples that are better adapted to living in high altitudes (see also: Andes Indians). could humans change into something vastly different? who knows... but if natural selection in humans were to truely take place, things like social welfare and society would have to be either eliminated or greatly reduced - "only the strongest survive" won't happen with everyone getting food (which isn't the case now of course, i know :-P)

p.s. i'm NOT suggesting we let all poor people starve or anything ludicrous like that! i was merely saying that, from a truely natural and emotionally-removed perspective, humans are slightly hindering their physiological evolutionary process.

again, i'm neither a "Master Race", nor eugenics enthusiast :rolleyes:

Of course there's no gene for "leg, etc". But with the want/need for them, it will certainly develop. And I don't mean to say birds put concious effort into making wings. What I'm saying is that birds, in the beginning, were probably constant prey. They needed someway to escape the predators. The body of these birds decided (Note I am once again being silly) "Meh. Why don't we get flying? Then they can't catch us!" And this then developed over a long time.

Hmm... So just because there's no experiment that is able to be performed, something is automatically untrue? That's what they are pretty much saying. And I think if a family of fish lived near the surface continually, and continually popped up out of the surface, I think the genes would eventually get passed down.

You don't get it. Lamarkianism claims that changes a being undertakes on themselves get passed down. A blacksmith's child would have bigger muscles because his father worked out. That sort of thing. This doesn't happen because heredity is genetic. It also means that evolution isn't driven by intention. We can roughly describe organisms as having "desire" to be certain things, but it's just a metaphor. Evolution can't plan, and can't see what options might be ahead. All it does is promote whatever is surviving best in the given span of variation. If there is a group of surface fish (for whatever reason) then the ones best able to be surface fish would survive, yes. Those traits might have side effects that would eventually mean that the best surface fish could do various land-type-things, which would make the fish that were better at land-type-things the ones that survived. Thus, land habitation evolves, not via desire or planning but via replication, variation, and selection.

Well I think most fish swimed to the surface to escape predators, most of which (during that time) were deep underwater. So I think the fish (who were probably essentially living on the surface) probably lived. And if you're going to ask what they ate, remeber algae?

If a fish today jumped up on the shore to escape a predator it would die, unless it got back in the water. Some fish did evolve the ability to survive out of the water(probably for a short period of time, but barring time travel I don't think we'll ever know), and they would have survived, and passed on their genes. This mutation didn't come about because they wanted to escape predators(if it did then why are there any fish at all, surely all of them wanted to escape predators?), but it allowed them to escape predators.

Hmm... So just because there's no experiment that is able to be performed, something is automatically untrue? That's what they are pretty much saying. And I think if a family of fish lived near the surface continually, and continually popped up out of the surface, I think the genes would eventually get passed down.
*TAKE TWO*
1) no, that means it's not scientifically valid. science only accepts ideas that are testible, repeatable, and falsifiable (don't worry about this point if it seems too complicated)
2) they were saying it was untrue because actions made during the giraffe's life didn't give it's kids longer necks: it was the genes inhierent at birth. humans have been circumcising males for over 4,000 years, but we're still born with foreskins!
3) you're getting closer to the mark here... the fish with genes making them better at surviving brief forays out of water would, over time, likely lead to a species of fish that could stay on land for longer and longer periods of time.

my point is not "their characteristics aren't passed onto the next generation." my point is "physical characteristics are passed onto the next generation via genetics (and new characteristics arise from slight mutations in said genetics)"

No, but the want to be able to constantly breath the air on the surface will.

I don't see how desire could possibly affect the genetic make up of an organism.

You don't get it. Lamarkianism claims that changes a being undertakes on themselves get passed down. A blacksmith's child would have bigger muscles because his father worked out. That sort of thing. This doesn't happen because heredity is genetic. It also means that evolution isn't driven by intention. We can roughly describe organisms as having "desire" to be certain things, but it's just a metaphor. Evolution can't plan, and can't see what options might be ahead. All it does is promote whatever is surviving best in the given span of variation. If there is a group of surface fish (for whatever reason) then the ones best able to be surface fish would survive, yes. Those traits might have side effects that would eventually mean that the best surface fish could do various land-type-things, which would make the fish that were better at land-type-things the ones that survived. Thus, land habitation evolves, not via desire or planning but via replication, variation, and selection.

Well what I meant to say is that fish didn't want to evolve, but that they probably needed to evolve, as either they grew more and more dependent on the surface air, or predators were making their advance up from the depths of the ocean.

Of course there's no gene for "leg, etc". But with the want/need for them, it will certainly develop. And I don't mean to say birds put concious effort into making wings. What I'm saying is that birds, in the beginning, were probably constant prey. They needed someway to escape the predators. The body of these birds decided (Note I am once again being silly) "Meh. Why don't we get flying? Then they can't catch us!" And this then developed over a long time.

What is your basis for saying that need for a certain mutation will cause it to develop?

Of course there's no gene for "leg, etc". But with the want/need for them, it will certainly develop. And I don't mean to say birds put concious effort into making wings. What I'm saying is that birds, in the beginning, were probably constant prey. They needed someway to escape the predators. The body of these birds decided (Note I am once again being silly) "Meh. Why don't we get flying? Then they can't catch us!" And this then developed over a long time.

No. It has to do it in gradual steps. It can't just think: "Oh, wings might be nice", especially since wings are relatively complex. It would be something more like: some of them have a small membrane, this helps stop them from dying from falls or whatever, so they survive, membrane size is useful, so bigger ones develop, then wings. Except not, because wings aren't membranes, but you get my point, it takes steps. Evolution doesn't predict where it's going, and every step has to be either useful or irrelevant.

*TAKE TWO*
3) you're getting closer to the mark here... the fish with genes making them better at surviving brief forays out of water would, over time, likely lead to a species of fish that could stay on land for longer and longer periods of time.

my point is not "their characteristics aren't passed onto the next generation." my point is "physical characteristics are passed onto the next generation via genetics (and new characteristics arise from slight mutations in said genetics)"

1. (Previously 3). That's what I just said.

2. That's essentially what I've been saying. The slight mutations eventually build up overtime to the point of where fish become completely dependent on surface air, thereby leading to the need to develop legs, but since fish obviously can't evolve legs in one generation, the genes slowly mutate, and with every new generation there is more and more leg, until the fish eventually are able to stay on land.

What is your basis for saying that need for a certain mutation will cause it to develop?

it keeps seeming like naliitr thinks animals/species are sentient master genetic scientists, doesn't it?

What is your basis for saying that need for a certain mutation will cause it to develop?

1. Didn't you yourself say the only way an animal could evolve is because they need the evolution.

2. It's called "ADAPTATION". If an animal is in an enviroment where it is having a difficult time, such as being hunted by predators, will lead to a need to escape the predators. The genes, in a sense, realize this need, and mutate in order to provide for this need, whether it is wings or legs, or something else.

it keeps seeming like naliitr thinks animals/species are sentient master genetic scientists, doesn't it?

No... I'm saying that the genes themselves are master genetic scientists. Scientists who research and develop for the family of animals they are currently residing in.

1. (Previously 3). That's what I just said.

2. That's essentially what I've been saying. The slight mutations eventually build up overtime to the point of where fish become completely dependent on surface air, thereby leading to the need to develop legs, but since fish obviously can't evolve legs in one generation, the genes slowly mutate, and with every new generation there is more and more leg, until the fish eventually are able to stay on land.

I think I get the issue here. There was no need for "leg". There was a need for a bit more muscular fin, or a bit more extended bone structure, or...you get it. It's not like at the beginning the fact that legs would be useful made things slowly progress to them, it was because the next step that, in this specific case, happened to lead to legs, was optimal. The step could've led to something completely different, evolution only cares about the immediate.

The basic point is that evolution doens't know what a leg is or what it could do until one happens to come about. And mutations happen not because they're useful, but because they can. Evolution only selects out of existing variation.

1. Didn't you yourself say the only way an animal could evolve is because they need the evolution.

2. It's called "ADAPTATION". If an animal is in an enviroment where it is having a difficult time, such as being hunted by predators, will lead to a need to escape the predators. The genes, in a sense, realize this need, and mutate in order to provide for this need, whether it is wings or legs, or something else.

no... you're making a "ipso facto, post facto" error (after the fact, therefore because of the fact). again, genes don't "realize" anything. a bunch of different variations exist, one happens to be more successful, that variation gets passed on. it happens again with more random variations, a few being successful.

after all is said and done, the species evolved into a different, more successful creature, but it was the passive result of environmental factors, not an active driving force from within the species, animal, or gene!

So what drives evolution then? A will to survive? Why would animals care if they lived or died?

no... you're making a "ipso facto, post facto" error (after the fact, therefore because of the fact). again, genes don't "realize" anything. a bunch of different variations exist, one happens to be more successful, that variation gets passed on. it happens again with more random variations, a few being successful.

after all is said and done, the species evolved into a different, more successful creature, but it was the passive result of environmental factors, not an active driving force from within the species, animal, or gene!

Yes, but wouldn't a gene mutation be successful depending on how it works for the animal in the ENVIROMENT?

Yes, but wouldn't a gene mutation be successful depending on how it works for the animal in the ENVIROMENT?

just recently there was news on how things that happened to a father during his lifetime could be passed on to his children. An emotional or stressfull experience are possibly being passed on through the fathers gene's. This could possible effect not only behaviour but possibly evolution.

Yes, but wouldn't a gene mutation be successful depending on how it works for the animal in the ENVIROMENT?

you missed my point. again. it might be too subtle... lemme try it this way:
EVENT 1: animals are born with random variations
EVENT 2: new environmental factor makes certian variations desireable
EVENT 3: desireable variation survives to produce offspring, passing on gene
*REPEAT EVENTS 1-3 AD INFINUM*
in word-form, it's saying "1 and 2 are independent of each other/not causal, though 3 happened due to the presence of 1 and 2"
earlier you said:
[EVENT 2]If an animal is in an enviroment where it is having a difficult time, such as being hunted by predators, will lead to a need to [EVENT 3]escape the predators. [EVENT 1]The genes, in a sense, realize this need, and mutate in order to provide for this need
you were saying "1 happened because of 2, and 3 happened because of that"

basically, you got the chain of causality mixed up

just recently there was news on how things that happened to a father during his lifetime could be passed on to his children. An emotional or stressfull experience are possibly being passed on through the fathers gene's. This could possible effect not only behaviour but possibly evolution.

Except it can't happen, because of how genes work. NEEEXT!

So what drives evolution then? A will to survive? Why would animals care if they lived or died?

Was this a question for Naitilir, a question for everybody else, or you being funny?

just recently there was news on how things that happened to a father during his lifetime could be passed on to his children. An emotional or stressfull experience are possibly being passed on through the fathers gene's. This could possible effect not only behaviour but possibly evolution.

if the environmental factor altered hsi genetic code, then yes. cancer, radiation, polution, some posions, old age, etc. CAN weaken the genetic structure, often leading to more and more profound genetic mutations (such as how parents over 40 are much more likely to have babies with Downs Syndrome, or two-headed snakes or 8-legged calves).

HOWEVER, the learned experiences aren't passed on, and that's what we keep trying to drive at. yes, a man could be so increadibly traumatized that he could get ulcers and stressed out, which would weakening his immune system, and that could lead to a disease that could alter a few genes. (pant-pant)

if you're claiming the actual emotion experience is passed on... well, that's speculation at best and pseudo-scientific religious mumbo-jumbo at worst :rolleyes:

No... I'm saying that the genes themselves are master genetic scientists. Scientists who research and develop for the family of animals they are currently residing in.

i wouldn't call genes master geneticists: i mean, they succeed only a tiny fraction of the time ;D

Was this a question for Naitilir, a question for everybody else, or you being funny?

if you're asking why life "keeps on truckin", then that's a philosophical debate you're looking for - and a really heavy one, at that. :p

this thread's for clarifying certian points of evolution ;)

Except it can't happen, because of how genes work. NEEEXT!

gee I guess I should try find out which group of researchers are doing the work and explain to them that an expert in a NS chat room told them their work is wrong. NEEEEEEEXT!

"sins of the father" as the discovery is being refferred to

gee I guess I should try find out which group of researchers are doing the work and explain to them that an expert in a NS chat room told them their work is wrong. NEEEEEEEXT!

"sins of the father" as the discovery is being refferred to

just based on what you told us, it's complete malarkie. if we could get more information, we'll address it accordingly. can you give us any references or links about what you're talking about? i'd really like to see what it's about. ("Sins of the Father" doesn't really help, since that's the name of four movies, about half a dozen books, two songs... and newspapers can entitle articles anything they want)

gee I guess I should try find out which group of researchers are doing the work and explain to them that an expert in a NS chat room told them their work is wrong. NEEEEEEEXT!

"sins of the father" as the discovery is being refferred to

Linky, SVP.

no... you're making a "ipso facto, post facto" error (after the fact, therefore because of the fact).


I thought it was called "post hoc, ergo proctor hoc."

Linky, SVP.

no linky, I heard it on the radio or tv last week(don't remember which).

life experiences imprinted on genes as they happen, interesting concept if their research holds up, would explain some of the weird behaviour I see in my kids.

might explain colective memory/ instinct

I thought it was called "post hoc, ergo proctor hoc."

doh! :( you're right!

you'd think i'd have noticed the simple fact that "post" means "after" in latin, not "ipso" :p

just recently there was news on how things that happened to a father during his lifetime could be passed on to his children. An emotional or stressfull experience are possibly being passed on through the fathers gene's. This could possible effect not only behaviour but possibly evolution.

If that's what they said then they were being metaphorical. The joke at Oxford is that there are genes for "having a good mother." Which means that genetically determined behaviors that result in taking good care of ones offspring make one's lineage more likely to thrive. Therefore the offspring can be said to have "genes for having a good mother." It's a joke.

If you inheret the effects of emotional trauma to your parents it's because you're being raised by traumatized parents who are likely to f-- you up in the head. Like those crazy stage mothers who put their kids in beauty pagents.

I thought it was called "post hoc, ergo proctor hoc."

on second thought, maybe i would have followed universal forum debate style if i had simply replied: "you're wrong:upyours: - AND you hate america!:sniper: :mp5: :mp5: !"



:p

just based on what you told us, it's complete malarkie. if we could get more information, we'll address it accordingly. can you give us any references or links about what you're talking about? i'd really like to see what it's about. ("Sins of the Father" doesn't really help, since that's the name of four movies, about half a dozen books, two songs... and newspapers can entitle articles anything they want)

From what I can tell, he is referring to the chances of epigenetic changes being passed on.

http://www.schizophrenia.com/sznews/archives/003842.html
http://www.sciencemag.org/cgi/content/short/308/5727/1373h

Most epigenetic changes refer to methylation and de-methylation of DNA. It doesn't alter the genetic code itself at all. What it does is alter the DNA polymer so that certain genes are accessed more or less depending on the level of methylation. Some epigenetic changes seem to be removed by the processes in a fertilized egg (cloning has demonstrated this pretty clearly - see the first cloned cat for an example), but it is very possible that some may not. Methylation and de-methylation of DNA occurs throughout a person's lifetime in response to all sorts of cues. Some genes, specifically in the extra X-chromosome in a woman, seem to be turned off almost permanently for her lifetime, but can reappear in her offspring.

Of course, we aren't talking about major mutations here. We are talking about alterations in hormone levels, increased or decreased fertility, etc. No genetic information is added or removed. The amount of access cells have to it is altered instead.

no linky, I heard it on the radio or tv last week(don't remember which).

life experiences imprinted on genes as they happen, interesting concept if their research holds up, would explain some of the weird behaviour I see in my kids.

might explain colective memory/ instinct

Look, only a very specific set of experiences can alter genes in any way. Radiation, for example. Emotions though? No, they don't. Instinct doesn't work by passing on experiences so much as passing on genetically determined responses to those experiences. Like if you automatically flinch when something flies at your head, you might have a better chance of passing on your genes than someone just standing there. That doesn't mean there's any imprinting involved.

Was this a question for Naitilir, a question for everybody else, or you being funny?

It's a question for everybody. I'm playing devils advocate.

From what I can tell, he is referring to the chances of epigenetic changes being passed on.

http://www.schizophrenia.com/sznews/archives/003842.html
http://www.sciencemag.org/cgi/content/short/308/5727/1373h

Most epigenetic changes refer to methylation and de-methylation of DNA. It doesn't alter the genetic code itself at all. What it does is alter the DNA polymer so that certain genes are accessed more or less depending on the level of methylation. Some epigenetic changes seem to be removed by the processes in a fertilized egg (cloning has demonstrated this pretty clearly - see the first cloned cat for an example), but it is very possible that some may not. Methylation and de-methylation of DNA occurs throughout a person's lifetime in response to all sorts of cues. Some genes, specifically in the extra X-chromosome in a woman, seem to be turned off almost permanently for her lifetime, but can reappear in her offspring.

Of course, we aren't talking about major mutations here. We are talking about alterations in hormone levels, increased or decreased fertility, etc. No genetic information is added or removed. The amount of access cells have to it is altered instead.

um... what he said! :D

It's a question for everybody. I'm playing devils advocate.

Umm...k...

Individual animals don't necessarily want to survive, but the ones that do survive and reproduce are the ones that determine what the next generation of animals are like. Thus, evolution moves populations towards greater survival chances.

It was a rather silly question, even for a devil's advocate.

um... what he said! :D

I went ahead and acessed the actual paper from Science. They don't actually rule out possible genetic mutations caused by the pesticides and fungicides they were using to induce the effect. They had evidence that pointed to epigenetic changes, but it was not conclusive and they make a point of saying so.

(and it's she) =)

From what I can tell, he is referring to the chances of epigenetic changes being passed on.

http://www.schizophrenia.com/sznews/archives/003842.html
http://www.sciencemag.org/cgi/content/short/308/5727/1373h

Most epigenetic changes refer to methylation and de-methylation of DNA. It doesn't alter the genetic code itself at all. What it does is alter the DNA polymer so that certain genes are accessed more or less depending on the level of methylation. Some epigenetic changes seem to be removed by the processes in a fertilized egg (cloning has demonstrated this pretty clearly - see the first cloned cat for an example), but it is very possible that some may not. Methylation and de-methylation of DNA occurs throughout a person's lifetime in response to all sorts of cues. Some genes, specifically in the extra X-chromosome in a woman, seem to be turned off almost permanently for her lifetime, but can reappear in her offspring.

Of course, we aren't talking about major mutations here. We are talking about alterations in hormone levels, increased or decreased fertility, etc. No genetic information is added or removed. The amount of access cells have to it is altered instead.

Hmm, sorta like the effects of the protein wrappers, etc. Cool.

I wouldn't think this would have a huge influence on evolution, though, as there's too much possible variation to allow for stable trends. Still, quite cool.

Umm...k...

Individual animals don't necessarily want to survive, but the ones that do survive and reproduce are the ones that determine what the next generation of animals are like. Thus, evolution moves populations towards greater survival chances.

It was a rather silly question, even for a devil's advocate.

Well the idea was to bring it out and draw to the line and point of why do Humans want to survive. Don't say we don't want to survive, have a better life, have a more comfortable life. How does evolution play into that?

Well the idea was to bring it out and draw to the line and point of why do Humans want to survive. Don't say we don't want to survive, have a better life, have a more comfortable life. How does evolution play into that?

You don't want to survive, you die. You don't have kids. If you have some sort of drive to survive, on the other hand, you do survive and have kids. So those with the drive to survive are the ones that pass on that drive to the next generation, thus filling the gene pool.

Hmm, sorta like the effects of the protein wrappers, etc. Cool.

I wouldn't think this would have a huge influence on evolution, though, as there's too much possible variation to allow for stable trends. Still, quite cool.

so I understand none of it, please explain more simple if possible.

Well the idea was to bring it out and draw to the line and point of why do Humans want to survive. Don't say we don't want to survive, have a better life, have a more comfortable life. How does evolution play into that?

again, that's the more in the relm of philosphy, since any species would inevitably link back to that "first life"... and why did it want to survive. The Meaning of Life, and all that

you missed my point. again. it might be too subtle... lemme try it this way:
EVENT 1: animals are born with random variations
EVENT 2: new environmental factor makes certian variations desireable
EVENT 3: desireable variation survives to produce offspring, passing on gene
*REPEAT EVENTS 1-3 AD INFINUM*
in word-form, it's saying "1 and 2 are independent of each other/not causal, though 3 happened due to the presence of 1 and 2"
earlier you said:

you were saying "1 happened because of 2, and 3 happened because of that"

basically, you got the chain of causality mixed up

I think I was trying to say: 1 happened because of 3, and 3 happens because of 2.

Except it can't happen, because of how genes work. NEEEXT!

Agreed.

i wouldn't call genes master geneticists: i mean, they succeed only a tiny fraction of the time ;D

And do you think master geneticists, who are humans themselves would succeced more than the genes themselves?

again, that's the more in the relm of philosphy, since any species would inevitably link back to that "first life"... and why did it want to survive. The Meaning of Life, and all that

But Philosophy comes from the mind, which is a part of the human body, which came from wherever according to evolution. How can you dismiss the two as seperate?

Look, only a very specific set of experiences can alter genes in any way. Radiation, for example. Emotions though? No, they don't. Instinct doesn't work by passing on experiences so much as passing on genetically determined responses to those experiences. Like if you automatically flinch when something flies at your head, you might have a better chance of passing on your genes than someone just standing there. That doesn't mean there's any imprinting involved.

unless those who reported it got it all wrong, they did imply that experiences could be imprinted. From my impression experiences would be along the lines of emotions, fear, aggression and such.

no linky, I heard it on the radio or tv last week(don't remember which).

life experiences imprinted on genes as they happen, interesting concept if their research holds up, would explain some of the weird behaviour I see in my kids.

might explain colective memory/ instinct

You should still be able to find it on google.

so I understand none of it, please explain more simple if possible.

I'm not sure this is what they're talking about, but in addition to your genes there are proteins wrapped around them. They protect them, and determine whether they're expressed. New developments indicate that they might have even more significance than we're currently aware of. In any case, changes in these proteins can occur during someone's life, at least to a certain extent, and if those changes reached the DNA in sperm and eggs they would get passed on to the proteins around childrens' DNA. In any case, I wouldn't think this would have a huge effect, but it might do something.

You don't want to survive, you die. You don't have kids. If you have some sort of drive to survive, on the other hand, you do survive and have kids. So those with the drive to survive are the ones that pass on that drive to the next generation, thus filling the gene pool.

And the drive to survive means, voila, making genetic mutations in order to survive.

unless those who reported it got it all wrong, they did imply that experiences could be imprinted. From my impression experiences would be along the lines of emotions, fear, aggression and such.

But that couldn't actually work, because such experiences wouldn't do anything to genes. Even the epigenetic stuff wouldn't be changed by overabundance of emotions.

And the drive to survive means, voila, making genetic mutations in order to survive.

The mutations aren't in order to survive, they just happen. They are then selected based upon which survive. That's the language problem you've been having all along.

And drive to survive in individuals has absolutely nothing to do with mutation. Whether you want your children to mutate or not will have no effect on whether they actually mutate.

And the drive to survive means, voila, making genetic mutations in order to survive.


But you can't control genetic mutations. Genetic mutations by definition are random, and almost any significant genetic mutation ends up in infertility or death, meaning that the genetic mutations would have to be slow and adaptable, assuming the same genetic mutation would happenchance be good enough to survive and make it more succesful and then mutate again.


it is because of that I have a hard time subscribing to the theory of macro evolution.

And do you think master geneticists, who are humans themselves would succeced more than the genes themselves?

Genes don't have planning. They can't imagine, they can't forsee, they work through trial and error, and they don't even plan out their trials. People can plan, can select based on what will happen as opposed to what does.

But you can't control genetic mutations. Genetic mutations by definition are random, and almost any significant genetic mutation ends up in infertility or death, meaning that the genetic mutations would have to be slow and adaptable, assuming the same genetic mutation would happenchance be good enough to survive and make it more succesful and then mutate again.


it is because of that I have a hard time subscribing to the theory of macro evolution.

Mutation+variation within a species act within certain parameters, that's inevitable. The tallest mouse is still a mouse. But if being the height of the tallest mouse is advantageous, then more of the mice will be the height of the tallest mouse in subsequent generations. Eventually, the range of variation will have moved up in height, and the tallest mouse will be much taller than any past mouse could've been.

Basically, change adds up. Macroevolution is really just a lot of microevolution over time.

But you can't control genetic mutations. Genetic mutations by definition are random, and almost any significant genetic mutation ends up in infertility or death, meaning that the genetic mutations would have to be slow and adaptable, assuming the same genetic mutation would happenchance be good enough to survive and make it more succesful and then mutate again.


it is because of that I have a hard time subscribing to the theory of macro evolution.

So by your reasoning birds just RANDOMLY evolved to have wings. And humans just RANDOMLY evolved to be the smartest species on earth. And cheetahs just RANDOMLY evolved to become the fastest land animal. It wasn't to escape predators? It wasn't to dominate our predators? It wasn't to catch prey?

I'm not sure this is what they're talking about, but in addition to your genes there are proteins wrapped around them. They protect them, and determine whether they're expressed. New developments indicate that they might have even more significance than we're currently aware of. In any case, changes in these proteins can occur during someone's life, at least to a certain extent, and if those changes reached the DNA in sperm and eggs they would get passed on to the proteins around childrens' DNA. In any case, I wouldn't think this would have a huge effect, but it might do something.

I checked the one link and it's from 2005, what I heard was released only last week.

If a chemical reaction to an event can effect the genes in the sperm then that could effect behaviour could it not? If it does then a normally agressive animal could become shy, in an extreme enviorment it could be the difference between extinction and survival. I know there have been mice bred to be unafraid/bold which is a fatal behaviour in mice. -Mice ran in the open rather than their normal behaviour of staying close to walls and cover.

Genes don't have planning. They can't imagine, they can't forsee, they work through trial and error, and they don't even plan out their trials. People can plan, can select based on what will happen as opposed to what does.

I'm not saying that they do. I'm saying that the body is giving them (in a sense) instructions on what to evolve. The body itself cannot evolve, so it's needs tells the genes what to evolve.

Macroevolution is the assumption that the process of adaptation of millions upon millions of years leads to the creation of new distinct species. There is no documented proof of this. I mean if you want to go to the fossil record, then feasibly there should be just as many "in between" species as there are previous and distinct species, as it's a process that occurs over billions of years and is constnatly going, because genetic mutation doesn't stop once a convenient and survivable species type is found.

no linky, I heard it on the radio or tv last week(don't remember which).

life experiences imprinted on genes as they happen, interesting concept if their research holds up, would explain some of the weird behaviour I see in my kids.

might explain colective memory/ instinct


Is it recent stuff on epigenetics you're thinking of ? If so, see the work of Marcus Pembrey, or Reik & Dean, amongst others :)

The basic idea is that the 'switches' of genes are not set in stone at conception, but can be altered by life experiences, certainly up to the point of initial gamete formation - usually life experiences that produce large hormonal or chemical changes, or extreme nutritional effects, etc. The example Pembrey used was tracking the intergenerational differences in a remote Swedish (? scandinavian, anyway) village - nutritional differences occasioned by famine in one generation predicted something... damn, no, sorry, I can't remember. It predicted something in the next generation, anyway.

And more longitutional research on a cohort of mothers and their kids who were caught up in the 9/11 disaster was being carried out - the kids had a stronger reaction to some stress hormone than other control groups of kids.

And Reik & Dean had similar results in their work on mice and rats - treat the experience of one set of rats in a certain way, and their offspring would differ from other rats who had not undergone the treatment.

If these researches are borne out, what you do in life may well effect your children by changing the nature of the genes that are transmitted, even if you don't reproduce till years or even decades have passed - quite a responsibility.

I'm not saying that they do. I'm saying that the body is giving them (in a sense) instructions on what to evolve. The body itself cannot evolve, so it's needs tells the genes what to evolve.

This goes back to the idea of survival. Why would an animal want to survive? Prolonged survival is not evolutionary beneficial. It is just another mouth to feed after breeding becomes impractical. Meaning for that to work, that has to be something encoded in the genes for them to want to survive, a purpose beyond natural selection/survival of the fittest.

I checked the one link and it's from 2005, what I heard was released only last week.

If a chemical reaction to an event can effect the genes in the sperm then that could effect behaviour could it not? If it does then a normally agressive animal could become shy, in an extreme enviorment it could be the difference between extinction and survival. I know there have been mice bred to be unafraid/bold which is a fatal behaviour in mice. -Mice ran in the open rather than their normal behaviour of staying close to walls and cover.

Behavior can change your chances of passing on your genes. That doesn't mean that experiences can have any effect on the genes themselves. Having bad things happen to you in life won't change the genes you pass on. This doesn't mean you can't pass on traits that would get you into bad situations, or traits that alter your reactions to bad situations, but if the bad situations just happen to you, they won't change your genes.

This goes back to the idea of survival. Why would an animal want to survive? Prolonged survival is not evolutionary beneficial. It is just another mouth to feed after breeding becomes impractical. Meaning for that to work, that has to be something encoded in the genes for them to want to survive, a purpose beyond natural selection/survival of the fittest.

So it's not embeded within the our instincts to survive? Then why is it that we run when we sense danger? Why do we fight back if someone is attacking? Why do we do whatever we can to SURVIVE?

Having bad things happen to you in life won't change the genes you pass on. .


Not true, chromosones can be damaged by physical trauma (atleast in guys) or radioactive exposure, and probably other things.

So it's not embeded within the our instincts to survive? Then why is it that we run when we sense danger? Why do we fight back if someone is attacking? Why do we do whatever we can to SURVIVE?

Quite the opposite, I believe in a Creator who encoded in our very genes the will to survive among other things. I firmly believe that there are things encoded in our genes, that were not just happenchance evolution by natural selection. I however do keep an open mind and am willing to listen to and debate arguements.

When I said I was playing devil's advocate, I didn't say I was playing it from one side to the other within the evolutionary debate, I meant that I am in a third party.

Macroevolution is the assumption that the process of adaptation of millions upon millions of years leads to the creation of new distinct species. There is no documented proof of this. I mean if you want to go to the fossil record, then feasibly there should be just as many "in between" species as there are previous and distinct species, as it's a process that occurs over billions of years and is constnatly going, because genetic mutation doesn't stop once a convenient and survivable species type is found.

There are as many "in between species" as you like, or there would be if people didn't tend to classify things in species. The species concept is just what we use for ordering our current world, but species still blend. A great example is this set of newt species around death valley: at the top there are two species of newt, and very clearly so. They don't and can't breed with eachother, and thus they are separate species. But, the newts at the top can breed with their neighbors to the south, who can breed with their neighbors to the south..so they're all breeds of a given species, right? Except that when you get to the southern end of the valley, and the two different "species" meet, both lines of newts can breed with eachother. So at one end of the valley, they're species, whilst at the other, they aren't? No, there are just variations along the valley, which add up from one north side to the other so that the northernmost ones are so different they can't breed, while the southern ones are exactly the same, to the point where it would be impossible to classify which was part of which "species". The same thing happens, not in space but in time, with evolution.

Not true, chromosones can be damaged by physical trauma (atleast in guys) or radioactive exposure, and probably other things.

Yes.

This is irrelevant, because the person I was responding to was suggesting that things beyond that might have an effect.

There are as many "in between species" as you like, or there would be if people didn't tend to classify things in species. The species concept is just what we use for ordering our current world, but species still blend. A great example is this set of newt species around death valley: at the top there are two species of newt, and very clearly so. They don't and can't breed with eachother, and thus they are separate species. But, the newts at the top can breed with their neighbors to the south, who can breed with their neighbors to the south..so they're all breeds of a given species, right? Except that when you get to the southern end of the valley, and the two different "species" meet, both lines of newts can breed with eachother. So at one end of the valley, they're species, whilst at the other, they aren't? No, there are just variations along the valley, which add up from one north side to the other so that the northernmost ones are so different they can't breed, while the southern ones are exactly the same, to the point where it would be impossible to classify which was part of which "species". The same thing happens, not in space but in time, with evolution.


That is a faulty analysis. Just because 2X2 and 2^2 are the same thing, doesn't mean that as the numbers grow greater with time that they will equal the same thing. 3X3 does not equal 3^3 nor does 3x2 equal 3^2. It is simply an assumption based on what limited information you have. There are way too many variables for macroevolution to be fact.

Yes.

This is irrelevant, because the person I was responding to was suggesting that things beyond that might have an effect.

Oops, sorry about that. Anyway I have to head off for awhile, I may be back later tonight, but doubtful. I have plenty of homework to keep me busy. Professors just like doing that to you, though admitadly my homework is light comparatively to others.

Quite the opposite, I believe in a Creator who encoded in our very genes the will to survive among other things. I firmly believe that there are things encoded in our genes, that were not just happenchance evolution by natural selection. I however do keep an open mind and am willing to listen to and debate arguements.

When I said I was playing devil's advocate, I didn't say I was playing it from one side to the other within the evolutionary debate, I meant that I am in a third party.

Oh ye gods...

Well, it's certainly creative.

Your argument is that evolution can't explain drive to survive past reproduction, and thus we need something else doing it (presumably something that thinks like us, though why I have no fucking clue). Evolution does explain extended drive towards survival, for two reasons. First, we humans decide to reproduce a lot less than our forebears would've, a lot of life that we don't reproduce in would still have been useful to early genes for reproduciton. Second, caring for future generations and helping them survive is also useful to help genes get passed down, and the drive could also exist for that. Third, evolution is fundamentally klugy. It uses what it can get. It could very simply be that it's too inefficient to have the survival drive turn off when reproduction becomes impossible, so instead we have a fairly constant survival drive. Fourth, people in the past didn't live very long past reproduction anyway, so stopping the survival drive when someone passes reproductive age would not be useful.

It's an interesting choice for an objection, but it's really one of the simple ones. Why don't you guys ever chose one of the real controversies, like sex? People still aren't sure why sex evolved, though there are hypotheses.

That is a faulty analysis. Just because 2X2 and 2^2 are the same thing, doesn't mean that as the numbers grow greater with time that they will equal the same thing. 3X3 does not equal 3^3 nor does 3x2 equal 3^2. It is simply an assumption based on what limited information you have. There are way too many variables for macroevolution to be fact.

This is by far the dumbest analogy I've ever encountered. Yes, if something looks like a math trend because you're only looking at one number, it might not be true. I really don't see what this has to do with what we're talking about. If small changes happen, then over lots and lots of time with fairly constant conditions they add up to big changes. It's not about 2x2=2^2 meaning 3x3=3^3, it's about 2+2=4, which is bigger, 2+2+2+2+2+2+2+2.....repeated over a billion years would produce a really big number. The algorithm works, that's all there is to it.

Oh ye gods...

Well, it's certainly creative.

Your argument is that evolution can't explain drive to survive past reproduction, and thus we need something else doing it (presumably something that thinks like us, though why I have no fucking clue). Evolution does explain extended drive towards survival, for two reasons. First, we humans decide to reproduce a lot less than our forebears would've, a lot of life that we don't reproduce in would still have been useful to early genes for reproduciton. Second, caring for future generations and helping them survive is also useful to help genes get passed down, and the drive could also exist for that. Third, evolution is fundamentally klugy. It uses what it can get. It could very simply be that it's too inefficient to have the survival drive turn off when reproduction becomes impossible, so instead we have a fairly constant survival drive. Fourth, people in the past didn't live very long past reproduction anyway, so stopping the survival drive when someone passes reproductive age would not be useful.

It's an interesting choice for an objection, but it's really one of the simple ones. Why don't you guys ever chose one of the real controversies, like sex? People still aren't sure why sex evolved, though there are hypotheses.


Actually, I've already gone over that quite alot with others when debating. In the simple sense that Sex would have evolved due to the simple fact that the variation provided by the random mating provided less chance for deadly genetic mutations that asexual species were quite prone too.

However you are still ignoring the fundamental drive for survival. Why?

However it was nice debating with you. It's much more enjoyable and enriching than debating with people who aren't as prominent in what they know about either creationism or evolution.

I bid thee adieu for now.

I'm not saying that they do. I'm saying that the body is giving them (in a sense) instructions on what to evolve. The body itself cannot evolve, so it's needs tells the genes what to evolve.

It's a very lose sense, and one that just confuses the matter. Evolution doesn't work on the level on individual reproduction, and your descriptions make it sound like it does. I think you get it, but you keep explaining it in a way that is exactly what confuses Scottie here. Your problem is linguistic.

This is by far the dumbest analogy I've ever encountered. Yes, if something looks like a math trend because you're only looking at one number, it might not be true. I really don't see what this has to do with what we're talking about. If small changes happen, then over lots and lots of time with fairly constant conditions they add up to big changes. It's not about 2x2=2^2 meaning 3x3=3^3, it's about 2+2=4, which is bigger, 2+2+2+2+2+2+2+2.....repeated over a billion years would produce a really big number. The algorithm works, that's all there is to it.

But you are assuming that it is done in the form of addition. It could be any series of set type of things. It is not a strict analogy other than to show that it is possible for patterns at small levels to be true but not at larger numbers, it was in no way meant to be a definitive statement on the nature of math and numbers.

Correlation is not always constant. It can be, but it isn't always, that was the point I was bringing.

Though I'm sure you could easily find dumber analogies if you try hard enough. As the old saying goes "if someone thinks they've found the stupidest thing they've ever seen, they aren't looking hard enough"

Actually, I've already gone over that quite alot with others when debating. In the simple sense that Sex would have evolved due to the simple fact that the variation provided by the random mating provided less chance for deadly genetic mutations that asexual species were quite prone too.

However you are still ignoring the fundamental drive for survival. Why?

However it was nice debating with you. It's much more enjoyable and enriching than debating with people who aren't as prominent in what they know about either creationism or evolution.

I bid thee adieu for now.

Just explained the survival drive...gah

Things that want in whatever sense we describe wanting need to want to survive, because things that want to survive are going to survive more than things that don't care, and thus will survive unto reproduction. The above post explains why many such drives continue after reproduction (though certainly not all. Salmon, for example, die shortly after spawning.)

As for the sex stuff, the issues gets more complicated by the fact that genes are selfish. What you described is the simplified, textbook picture, but there still is a large amount of debate over the details. Dawkins' most recent book, Ancestor's Tale, refuses to comment on which hypothesis will bear fruit.

But you are assuming that it is done in the form of addition. It could be any series of set type of things. It is not a strict analogy other than to show that it is possible for patterns at small levels to be true but not at larger numbers, it was in no way meant to be a definitive statement on the nature of math and numbers.

Correlation is not always constant. It can be, but it isn't always, that was the point I was bringing.

Though I'm sure you could easily find dumber analogies if you try hard enough. As the old saying goes "if someone thinks they've found the stupidest thing they've ever seen, they aren't looking hard enough"

My point is, it's not an issue of correlation, but of algorithm. 2+2=4 not because we've tried it and found it so, but because that's what it is by definition. Similarly, evolution is the algorithm of replication, variation, and selection. This will always produce evolution because that's what it does, and it doesn't stop at the "micro" level because there's nothing there to stop it. If there are a bunch of different things out there, and the differences can be passed on, and not all of the things will survive, and that survival chance is at least somewhat based on the differences, then differences will accrue to make survival more likely. This happens as many times as you like, and gets farther each time. Millions of years=millions of small changes in the same direction=big changes. Microevolution implies macroevolution because the only differences are arbitrary.

The 'will to survive' exists because it can, because in many cases in which it does occur it increases survival (and so net reproductive rate), and because at least one of the pathways to the effect we refer to as 'the will to survive' is subject to genetic influences (in other words it is/they are heritable). Given these three facts, it would be stranger for the will to survive not to exist than for it to exist.

With regards to longevity being another mouth to feed, in the case of humans this objection doesnt hold up in the face of the facts. Reproductively immature humans generate an energy deficit (they need more energy than they can independently obtain from the environment). However mature humans can in many environments generate an energy surplus. A post-menopausal female then can generate more energy in many environments than she requires and this surplus energy can be invested in her descendants.

unless those who reported it got it all wrong, they did imply that experiences could be imprinted. From my impression experiences would be along the lines of emotions, fear, aggression and such.

Based on what I have read, anything that said this misrepresented it. Certain life experiences can lead to hormonal changes, and therefore, epigenetic changes. The actual experiences, however (ie. emotions, fear) would not be passed on. A person who underwent stress and ended up with very high (or low) amounts of certain hormones may have epigenetic changes that are passed on. The child, however, would not have any memory of that stress or be afraid of the same things, etc. They might be more jumpy, more prone to stress in general - that sort of thing.

So by your reasoning birds just RANDOMLY evolved to have wings. And humans just RANDOMLY evolved to be the smartest species on earth. And cheetahs just RANDOMLY evolved to become the fastest land animal. It wasn't to escape predators? It wasn't to dominate our predators? It wasn't to catch prey?

No. Mutations that eventually led to wings occurred randomly. Because those mutations were beneficial, they were selected for in the population. The mutation is random. Natural selection is not.

However, a possible open niche in an ecosystem is not going to cause a specific mutation. If that mutation happens, it will be selected for. If it doesn't, something else will be selected for.

I'm not saying that they do. I'm saying that the body is giving them (in a sense) instructions on what to evolve. The body itself cannot evolve, so it's needs tells the genes what to evolve.

And this would be patently incorrect. There is no evidence that the body causes mutations to happen in response to stimuli. In fact, the body contains all sorts of mechanisms to try and prevent mutation (although some mutation is still inevitable).

Based on what I have read, anything that said this misrepresented it. Certain life experiences can lead to hormonal changes, and therefore, epigenetic changes. The actual experiences, however (ie. emotions, fear) would not be passed on. A person who underwent stress and ended up with very high (or low) amounts of certain hormones may have epigenetic changes that are passed on. The child, however, would not have any memory of that stress or be afraid of the same things, etc. They might be more jumpy, more prone to stress in general - that sort of thing.

And even that seems unlikely. I mean, what're the chances that stress specifically damages the proteins around the stress gene, as opposed to other proteins? While I could see some stuff getting passed on, it would be too erratic to have much of an evolutionary effect.

No. Mutations that eventually led to wings occurred randomly. Because those mutations were beneficial, they were selected for in the population. The mutation is random. Natural selection is not.

However, a possible open niche in an ecosystem is not going to cause a specific mutation. If that mutation happens, it will be selected for. If it doesn't, something else will be selected for.



And wings are actually a pretty good example of this issue. Fully formed wings simply won't spontaneously mutate on something, so even if various species might find them useful, it's not going to happen. Instead, wings are the result of a series of incremental changes, each one beneficial in and of itself, and each one part of existing variation.

hey guys, I thought this was a non-debate thread;)

And even that seems unlikely. I mean, what're the chances that stress specifically damages the proteins around the stress gene, as opposed to other proteins? While I could see some stuff getting passed on, it would be too erratic to have much of an evolutionary effect.


you discounted it completely earlier, so...the fact that someone thinks stress can have an effect and their research seems to back it up...so if it does how much does it do so? many mysteries yet to be dicovered in the human body, wasn't long ago DNA was discovered and how much has been learned since then....

I agree it would may be too eratic to have much of an evolutionary effect but under the right circumstances it could in isolated instances...

Except it can't happen, because of how genes work. NEEEXT!


Hooold on there Tex-Rex.

you are being a little simplistic. The fathers actions CAN and do affect his genes. This is well proven. A gene is expressed through assemblage by mitochondria in the cells of his body, and in the presence of enzymes in the right quantity and at the right times.

The fathers sperm production is dependant on the right enzymes and amino acids, again, at the right time, place and quantity. Sperm are a very close copy of the fathers genes, but even within his body, cells are not perfectly genetically identical. Sperm are not perfect copies.

Now for the action phase. Many things the father does in his life will affect his body to reproduce his genetic code, such as drugs, eating foods high in oxidants, stress, exposure to mutagens, and things such as disease inhibiting production of enzymes. Even his own mutations can have secondary effects in his children.

A good example would be scurvy, which is caused by lack of vitamin C, and results in death from the body not being able to produce the amino acids it needs.

So the lifestyle, action and history of the father directly influences the quality, purity(genetic makeup) and quantity of the sperm that passes his DNA to his offspring.

We are each 50 percent of our father, fifty percent of our mother, with a small helping of mutation.... from before conception. No copy is perfect.

you are being a little simplistic. The fathers actions CAN and do affect his genes.

Indeed. But what V-R was saying is that experiences cannot be passed on through the genes. If I have a bad experience with spiders, my genes aren't going to change so that my children are born terrified of spiders - that sort of thign.

This is well proven. A gene is expressed through assemblage by mitochondria in the cells of his body, and in the presence of enzymes in the right quantity and at the right times.

I think you are a bit confused as to what mitochondria actually do. A gene is expressed through transcription, modification of RNA, and then translation - none of which directly involve the mitochondria.

Hooold on there Tex-Rex.

you are being a little simplistic. The fathers actions CAN and do affect his genes. This is well proven. A gene is expressed through assemblage by mitochondria in the cells of his body, and in the presence of enzymes in the right quantity and at the right times.

The fathers sperm production is dependant on the right enzymes and amino acids, again, at the right time, place and quantity. Sperm are a very close copy of the fathers genes, but even within his body, cells are not perfectly genetically identical. Sperm are not perfect copies.

Now for the action phase. Many things the father does in his life will affect his body to reproduce his genetic code, such as drugs, eating foods high in oxidants, stress, exposure to mutagens, and things such as disease inhibiting production of enzymes. Even his own mutations can have secondary effects in his children.

A good example would be scurvy, which is caused by lack of vitamin C, and results in death from the body not being able to produce the amino acids it needs.

So the lifestyle, action and history of the father directly influences the quality, purity(genetic makeup) and quantity of the sperm that passes his DNA to his offspring.

We are each 50 percent of our father, fifty percent of our mother, with a small helping of mutation.... from before conception. No copy is perfect.

again, those are physiological effects. physical. high stress or drugs or pesticides won't transfer a memory to a child!

again, those are physiological effects. physical. high stress or drugs or pesticides won't transfer a memory to a child!

Quite correct. No memory is transfered. You couldnt possibly have enough DNA to store all that information anyway.

As for the other poster, yes, I misused mitochondria. It is the ribosomes that build proteins. Thanks for the heads up.

This explains it all:
http://www-astro.physics.ox.ac.uk/~hansen/pics/moment.jpg

One thing worth keeping in mind is that mutations don't have to be GOOD or BAD - they can also be NEUTRAL.

So, let's take a population of mice, living in a field with no predators.

Mutations in tail length occur. Some have longer tails, some have average tails, some have stubby tails. There is no 'need' for different tail lengths - it just happens because each generation of mice will contain a certain percentage of imperfect babies, which differ in various ways from their parents. In this situation, tail length IN NO WAY effects breeding chances - no one tail length is selected against, so they all breed roughly equally.

Now - let's add some environmental pressure. A predator moves into the field. It's method of catching prey involves grabbing them by an extremity (ie a tail) and holding on.

Now, obviously the long tailed mice are STRONGLY selected against, the average tails are SLIGHTLY selected against, and the stubby tails are NOT selected against.

Within a few generations, you will see long tails all but disappear, and stubby tails make up the vast majority.

Now, is this because the bodies of the mice went 'oh bugger, predators. genes, make shorter tails!', or is it because the mice with longer tails got eaten?

Birds did not 'need' to develop wings to escape predators - birds which had (random) wing-like mutations were better able to escape predators, and so LIVED to produce offspring with more extreme wing-like mutations.

Cheetars did not 'want' to evolve speed to catch prey - the cheetars that were (randomly) faster caught more food and LIVED to breed even faster offspring.

Bad things die off and good things live, so any population will have many good things and few bad things. But neutral things remain until the environment changes and they BECOME good or bad.

This explains it all:
http://www-astro.physics.ox.ac.uk/~hansen/pics/moment.jpg

Hehe, use that all the times in my teaching =)

Here is another nice one to use for education:

Indeed. But what V-R was saying is that experiences cannot be passed on through the genes. If I have a bad experience with spiders, my genes aren't going to change so that my children are born terrified of spiders - that sort of thign.

Is there a confusion over the term 'experiences'? In the context of epigenetics, it's only trying to get across the idea that there's more to inheritence than pure genetics - that your nutrition, abnormal hormone production, radiation/chemical effects etc. can effect the genes you pass down to your offspring.

The origins of these effects are 'experiential' in that they're things that happened during your lifetime that were not laid down in your genetic code, but rather occured as a result of your upbringing, or day to day life at sensitive periods.

An experience is being defined as an extra-genetic factor that nevertheless had an effect on the genes transmitted to the next generation, and this 'experiential factor' was dependant on the world/situation that the parent was born into or grew up in, that's all. It's not talking about inherited memories or the like.

Is there a confusion over the term 'experiences'? In the context of epigenetics, it's only trying to get across the idea that there's more to inheritence than pure genetics - that your nutrition, abnormal hormone production, radiation/chemical effects etc. can effect the genes you pass down to your offspring.

The origins of these effects are 'experiential' in that they're things that happened during your lifetime that were not laid down in your genetic code, but rather occured as a result of your upbringing, or day to day life at sensitive periods.

An experience is being defined as an extra-genetic factor that nevertheless had an effect on the genes transmitted to the next generation, and this 'experiential factor' was dependant on the world/situation that the parent was born into or grew up in, that's all. It's not talking about inherited memories or the like.

One note, because it wasn't really clear what you meant here:

Nothing has suggested that experiences dictate which genes will be passed on and which will not, nor that the genetic code itself is altered by most experiences (other than actual mutation-causing experiences such as radiation). Stresses, nutrition, etc. seem to change the genes of a person epigenetically - changing the way in which genes are used, not the actual genetics. These epigenetic changes, from what we have seen, are usually reversed when development begins in a fertilized egg cell. However, some may not be and may be passed on.

Free Sex and Beer referred to (or seemed to refer to) actual experiences being imprinted and passed on, not to experiences making changes that were then passed on.

So by your reasoning birds just RANDOMLY evolved to have wings. And humans just RANDOMLY evolved to be the smartest species on earth. And cheetahs just RANDOMLY evolved to become the fastest land animal. It wasn't to escape predators? It wasn't to dominate our predators? It wasn't to catch prey?

No. All those things happened because of 'random' mutation... but they were 'selected for' by survival factors in the environment.

For example - the characteristic that led to the evolution of the cheetah, MIGHT have been that peculiar metabolic 'switch' that actually seems to oppose good sense - the ability of the cheetah to expend a far-too-high amount of energy.

When such a mutation first happened, one can assume that we would be looking at a mutant form of some basic wild cat... not some sleekly designed roadster that we see today.

In areas where the food supply was short, the mechanism that doesn't inhibit energy release would probably be a 'negative mutation'... by which I mean, the cat would overheat, or exhaust itself, far more often than it would be successful. Natural selection would NOT favour this mutation, and that line would die out.

On the other hand, if the mutation was exhibited where food was plentiful, the ability to 'break' the metabolic rules a little would not be negative. And - as the food supply had it's weaker/slower bloodlines weeded out by predatory actions, it would actually become a benefit.

What you then have is a relationship. Only the fastest and most agile prey survive to pass on their genes... so the prey become faster and more agile. Which means - only the fastest and most agile predators get to eat, and pass on THEIR genes... so the predators becomes faster and more agile.

The Cheetah didn't just see a niche and jump into it.


And, who told you humans were the smartest species on earth?