NationStates Jolt Archive

The BBC has an interesting article about how the human face has changed over the last 650 years. Based on skull measurements, it appears that people living in the middle ages had more pronounced facial features yet smaller foreheads than modern humans do. This seems to show that we are still evolving. Though I'd like to see more research to confirm it. Any thoughts?

http://news.bbc.co.uk/2/hi/science/nature/4643312.stm

We are always evolving. Evolution doesn't simply just stop and go "ok, good enough." Its a process of nature just like the water cycle or gravity.

If your main point for this was as evidence, there's already plenty. It is clear that we are evolving because all organisms evolve, just by the way evolution works alone.

The article is still pretty interesting though.
Dr Peter Rock, lead author of the study and director of orthodontistry at Birmingham University, told the BBC News website: "The astonishing finding is the increased cranial vault heights.

"The increase is very considerable. For example, the vault height of the plague skulls were 80mm, and the modern ones were 95mm - that's in the order of 20% bigger, which is really rather a lot."

He suggests that the increase in size may be due to an increase in mental capacity over the ages.
Ooh, I'd be really wary about jumping to that conclusion after most of the stuff I've heard about brain size. AFAIK, having a physically larger brain isn't the largest factor in human intelligence. Then again, I'm no expert.

This seems to show that we are still evolving. Though I'd like to see more research to confirm it. Any thoughts?

you need to take into account social evolution as well. tastes change.. what was considered beautiful in 1200 may now be ugly. people breed with looks in mind (a lot of the time).. and i think that needs to be considered. long ago it was sexy, maybe, to have smaller of bigger foreheads.. or more or less prominent teeth or something.. bigger noses or higher cheekbones. social evolution.. depeche mode. ;)

uhhh.. other creatures are evolving. why not us. however, i think ours is more socially linked than otherwise. natural evolution can't move that fast, far as i know.

We are always evolving. Evolution doesn't simply just stop and go "ok, good enough." Its a process of nature just like the water cycle or gravity.

gravity is NOT a "process."

In order to evolve, the least fit must perish, and the fittest survive and breed. Since only very serious genetic defects cause people to die nowadays, not a great deal of evolution is going on.

No! Of course not God just ddecided to chage the shape of our heads! </sarcasm>

Of course we're still evolving. Evolution wont stop until life stops.

having a physically larger brain isn't the largest factor in human intelligence.

i'm currently taking human anatomy&physiology2.. and i can confidently say that brain size plays NO part in intelligence at all. not even taken into account, ever. ;)

Vegetarianistica']gravity is NOT a "process."

So you don't believe in gravitrons?

Vegetarianistica']i'm currently taking human anatomy&physiology2.. and i can confidently say that brain size plays NO part in intelligence at all. not even taken into account, ever. ;)

i should add that it's the amount of Folds in the brain that matters. the more folds, the more intelligent .. if you're comparing species. in humans we're not sure what makes some more intelligent than others. seems to be how they categorize their 'space.' ;)

So you don't believe in gravitrons?

Gravitrons are the sh*t !!! :)

Vegetarianistica']i'm currently taking human anatomy&physiology2.. and i can confidently say that brain size plays NO part in intelligence at all. not even taken into account, ever. ;)
Hurray, I was somewhere sort of vaguely near the right idea!
*pats self on back*

In order to evolve, the least fit must perish, and the fittest survive and breed. Since only very serious genetic defects cause people to die nowadays, not a great deal of evolution is going on.

Actually, evolution is still going on. Evolution is a series of minor mutations that may produce slight variations in character traits. The vast majority of such variations have no effect. Others have detrimental effect and a very rare few have beneficial effect. If the individual with these beneficial trait survives and breeds with greater success than those without the trait, that trait becomes the new standard for the species.

Considering the amount of traits we now posess as human beings, it is clear that the variation of beneficial traits and detrimental traits we can possess and still survive is fairly broad. But there are as yet unquantifiable traits that are still undergoing occasional mutation. For instance; we are evolving into more socially dependent creatures.

In order to evolve, the least fit must perish, and the fittest survive and breed. Since only very serious genetic defects cause people to die nowadays, not a great deal of evolution is going on.
I think you're barking up the wrong tree here.
You have to take into account that "fittest" is relative to their environment. Our technological change has changed our environment, and made 'fitness' different. It is no longer necessarily a very 'unfit' trait to have asthma, or some mild genetic disease or other, because we still survive to breed even if we have those traits, in our changed environment.

Vegetarianistica']i'm currently taking human anatomy&physiology2.. and i can confidently say that brain size plays NO part in intelligence at all. not even taken into account, ever. ;)

i read something about this awhile ago....something about the first people migrating out of africa. originally they thought only homo erectus (tee hee) had a big enough brain to be able to handle intercontinental travel... but later they found bones outside of africa of homo habilis (a less developed cousin of ours), which has a significantly smaller brain. It didnt seem to make any sense but there was no denying what they found

here is something fun you can do:

feel the pinkie knuckle on the side that faces out you should (unless your not evolved enough and thus should become extinct soon) feel a bump on one or both of your knuckles guess what...that’s your 6th finger in a few million years you will see it more clearly (unless you already have a sixth finger and thus are a witch)

evolution at work! *drools over everyone touching themselves at my command*

Actually, evolution is still going on. Evolution is a series of minor mutations that may produce slight variations in character traits. The vast majority of such variations have no effect. Others have detrimental effect and a very rare few have beneficial effect. If the individual with these beneficial trait survives and breeds with greater success than those without the trait, that trait becomes the new standard for the species.

Considering the amount of traits we now posess as human beings, it is clear that the variation of beneficial traits and detrimental traits we can possess and still survive is fairly broad. But there are as yet unquantifiable traits that are still undergoing occasional mutation. For instance; we are evolving into more socially dependent creatures.

A good point, well made.

Vegetarianistica']gravity is NOT a "process."
I'd love to see you prove this. There is deep and serious division among scientists about what gravity is.

I'd love to see you prove this. There is deep and serious division among scientists about what gravity is.

Indeed there is.

here is something fun you can do:

feel the pinkie knuckle on the side that faces out you should (unless your not evolved enough and thus should become extinct soon) feel a bump on one or both of your knuckles guess what...that’s your 6th finger in a few million years you will see it more clearly (unless you already have a sixth finger and thus are a witch)

evolution at work! *drools over everyone touching themselves at my command*

I've heard that having a sixth finger is actually a dominant trait and one that pops up occasionally.

Vegetarianistica']i'm currently taking human anatomy&physiology2.. and i can confidently say that brain size plays NO part in intelligence at all. not even taken into account, ever. ;)

Except in psudeo-science, like phrenology et al.

Frankly this doesn't suprise me much - I've thought before that humans over time probably evolve to become more aesthetically pleasing. After all, it plain makes sense that the more handsome you are the better advantage you've got when it comes to passing on your genes.

I actually considered it when thinking how it seems to me that although obviously you get ugly brainy people and beautiful dumb people, overall I think intelligent people are more likely to be attractive than stupid people. This is probably because intelligence gives a person a better chance of getting a better looking mate, even if they themselves are not attractive, and so both looks and smartness are often passed down together.

We are always evolving. Evolution doesn't simply just stop and go "ok, good enough." Its a process of nature just like the water cycle or gravity.

In the case of humans, at least, that isn't quite true. Because humans are civilized, our evolution has slowed to crawl, if not a dead stop. In the wild, the less successful, talented, strong, fit, etc. die, or at least don't do as well. In a civilization, less successful members are preserved and protected, threats to life, limb, property, rights, etc. are communally defended against, etc.

The less successful survive just as readily as the more successful, and often have more children. Because of that, natural selection via survival of the fittest has been short-circuited and undermined, grinding evolution to a halt or near-halt. It's a paradox; sapience is apparently the most complex and high-information/energy-structure result of evolution, but it leads to civilization, which is an evolutionary dead-end. The only way out of that cul-de-sac is, of course, self-directed artificial evolution via bioengineering, AI, uploading, intelligence amplification, etc.

Really, we've just changed who's "fittest", used to be the one who could get more food, now it's based almost solely on attracting a mate, or as many mates as possible.

I'd love to see you prove this. There is deep and serious division among scientists about what gravity is.

gravity is not a process. what it is i don't know. i do know that space-time curves around gravity. i can't imagine space-time curving around a 'process.' if you can find me even ONE scientifically feasible quote using the words 'gravity' and 'process,' i'll rest my case. otherwise, yeah, we don't know what it is. but i believe the common thing is to call it a 'force.'

The less successful survive just as readily as the more successful, and often have more children. Because of that, natural selection via survival of the fittest has been short-circuited and undermined, grinding evolution to a halt or near-halt. It's a paradox; sapience is apparently the most complex and high-information/energy-structure result of evolution, but it leads to civilization, which is an evolutionary dead-end. The only way out of that cul-de-sac is, of course, self-directed artificial evolution via bioengineering, AI, uploading, intelligence amplification, etc.

Evolution is not the progress of a species into something 'better', it is merely the progress of a species into something different. If the traits of the 'less successful' propagate, it's no less evolution than if more successful people passed on their traits the most.

Though I would probably agree that humanity's general control of our living environment has probably stopped anything big from happening evolution-wise. Then again, have most large animals really evolved much recently?

In the case of humans, at least, that isn't quite true. Because humans are civilized, our evolution has slowed to crawl, if not a dead stop. In the wild, the less successful, talented, strong, fit, etc. die, or at least don't do as well. In a civilization, less successful members are preserved and protected, threats to life, limb, property, rights, etc. are communally defended against, etc.

The less successful survive just as readily as the more successful, and often have more children. Because of that, natural selection via survival of the fittest has been short-circuited and undermined, grinding evolution to a halt or near-halt. It's a paradox; sapience is apparently the most complex and high-information/energy-structure result of evolution, but it leads to civilization, which is an evolutionary dead-end. The only way out of that cul-de-sac is, of course, self-directed artificial evolution via bioengineering, AI, uploading, intelligence amplification, etc.
It has not been stopped, because it can't be. The mere fact that people survive to breed shows that they are fit, even, as far as I know surviving and breeding is basically the definition of fit.
Fitness doesn't necessarily mean stronger, or more talented, or any of that. Look at the situation with the small mammals vs. the dinosaurs. Dinosaurs died off due to whatever reason, but the physically weaker and smaller mammals survived.
You don't need to be strong as a prerequisite for fitness unless your environment requires it, and ours doesn't.

We are always evolving. Evolution doesn't simply just stop and go "ok, good enough." Its a process of nature just like the water cycle or gravity.
As long as their is envyromental pressure to do so... though it will be intresting to see what takes place as we remove phisical pressures.

Evolution, like all fads, ended way back when in the 70s. When disco was born, evolution died of a heart failure due to cholesterol build-up.


~Alan Smithee
Puppet of [censored]~

Well it really goes down to a scientific level, look at the medievil ages, back then people drank urin, killed each other, and were basicly almost un-organized. but now we have computers, hockey sticks, flying metal birds, so coming to this conlusion; as we change our surrounding, our surroundings change us

Evolution is not the progress of a species into something 'better', it is merely the progress of a species into something different. If the traits of the 'less successful' propagate, it's no less evolution than if more successful people passed on their traits the most.

Though I would probably agree that humanity's general control of our living environment has probably stopped anything big from happening evolution-wise. Then again, have most large animals really evolved much recently?
Not unless you call extinction evolution. IIRC, 90% of most animals over 40lbs died around the time we came along. It appears though, that it wasn't entirely our fault.

Well it really goes down to a scientific level, look at the medievil ages, back then people drank urin, killed each other, and were basicly almost un-organized. but now we have computers, hockey sticks, flying metal birds, so coming to this conlusion; as we change our surrounding, our surroundings change us

Heheh. So true. Though some physical differences between now and then probably aren't genetic. I mean, people nowadays are giants compared to your average joe medievil times, but that's probably due to better nutrition or the consumption of exhorbant amount of sugar more than anything.

In the case of humans, at least, that isn't quite true. Because humans are civilized, our evolution has slowed to crawl, if not a dead stop.

I'd Like to tell you no thats not true, but I cant, any more than you can validly make your claim. From What I can see, modern social pressures are creating stresses that CAN be selected against, such as Irregular sleep patterns, wide spectrum light levels, Excessive ambient noise levels, Changes in nutrient requirementsand things such as adaptation to new strains of virus, bacteria, and other diseases.

As well, there are the social factors that must be dealt with, such as charges in instinctual threat analysis(is that guy gonna mug me?),Increased selection for people that can juggle social ativities and sustenance gathering(excessive work AND a love life), emotional evolution due to the fact that we no longer have large familial groups for emotional support...

The american dental association(they've kept records longest) have data showing that in the last 300 years, our jaws are shrinking, likely because of better prepared foods, and foods that are more refined. This would both be a genetic thing, and an environmental adaptation. Tooth alignment issues are on the rise because of this; we dont need large surface area jaws to sufficiently chew our food, but smaller jaws cannot hold 32 teeth properly.

Another factor that must be selected for is a prolonged life, and offset reproduction age. As people spend more of their lives as students, they also remain immature longer, and hold off on having children.

It is said that the only thing evolution doesnt select against is death, because after people are finished reproducing, mutations to their genetics do not reenter the gene pool. So reproduction age and death age are strongly tied together.

As people extend their lives and routinely have children in their late 30s, 40s, and even 50s, we will be subjected to forces and genetics that keep our bodies young right up til the point of death. Remember that 100 years ago, 50 years old was the maximum avaerage life expectancy. Things like female menopause are being offset later and later. With the advent of drugs like viagra, we can expect middle aged pregnancies to become more common, and life expectancies to increase.

Eh, don't the chances of things like Down's Syndrome in the child increase with the mothers age?

Eh, don't the chances of things like Down's Syndrome in the child increase with the mothers age?

I think so, yes. Something about how as the body ages you start getting more errors in cell division, including in the gametes.

Heheh. So true. Though some physical differences between now and then probably aren't genetic. I mean, people nowadays are giants compared to your average joe medievil times, but that's probably due to better nutrition or the consumption of exhorbant amount of sugar more than anything.

Actually, our height today is about the same as it was during the Roman Empire and the Dark Ages. It was only after we started clustering in dirty medieval cities with childhood diseases and malnutrition that we started to "shrink". It more or less hit its peak during the Industrial Revolution, and after that we started to increase in height again.

It's probably unlikely that, unless something drastic changes in our enviroment, humans will evolve significantally in the near future. We seem to have found a niche that suits us nicely. Look at how little turtles and sharks have changed over the years.

What we might see happening is increased resilience to pollution as cities and pollution spreads. But this will probably be more drastic in plants and non-human animals then it will in us.

Of course, I'm be no means an expert, and you should not, under any circumstances assume that I really know what I'm talking about. I'm just conjecturing from what seems to make sense.

So, where's the ID and Creationists?

Eh, don't the chances of things like Down's Syndrome in the child increase with the mothers age?

Yes. The incidence of Down's Syndrome increases 100x (yes, 100x not 100%) for women who have children over the age of 35 (in the USA). It has to do with how long the immature gametes are held in stasis before completing meiosis and being released as a mature egg.

As far as the original topic is concerned, it's just too soon to say whether or not this is evidence of human evolution. Consider the changes in nutrition and sanitation since that time. A change in expression of genes does not indicate a change in genes. Furthermore, the article does not mention the make-up of the group the old skulls were compared to. Increased immigration may have changed the local gene pool (which is not evidence of evolution).

Vegetarianistica']i'm currently taking human anatomy&physiology2.. and i can confidently say that brain size plays NO part in intelligence at all. not even taken into account, ever. ;)

...excepting any values of brain size 0.

Actually, our height today is about the same as it was during the Roman Empire and the Dark Ages.

Explain to me why the average Roman soldier was between 1.48 and 1.65 metres tall (second and third century AD), would you?

im no expert, im just wondering, can diet change things a little, things such as today we are recieving alot more calcium, and necesarry vitamins, if someone today was to eat exactly what they ate then, would their skull also be different?

As people extend their lives and routinely have children in their late 30s, 40s, and even 50s, we will be subjected to forces and genetics that keep our bodies young right up til the point of death. Remember that 100 years ago, 50 years old was the maximum avaerage life expectancy. Things like female menopause are being offset later and later. With the advent of drugs like viagra, we can expect middle aged pregnancies to become more common, and life expectancies to increase.

It isn't added lifespan that's being selected for per se, but rather increased reproductive activity, and that is only in its nascent stages (contrary to conventional wisdom, the average age of menopause is still 35; most of those women who are giving birth in their 50's are first extremely aberrant, and second giving birth to children that aren't theirs biologically speaking).

Evolution is not the progress of a species into something 'better', it is merely the progress of a species into something different. If the traits of the 'less successful' propagate, it's no less evolution than if more successful people passed on their traits the most.

The point is that process which causes certain traits to be propogated more than others is called natural selection, which is driven by survival of the fittest. If unsuccessful traits are of equal or random propogation likelihood compared to successful traits, there is no functioning definition of fittest, no particular trait or fitness paradigm is being selected for, and evolution does not continue. You have to have adaptive pressure to select for the fittest, and civilization takes that away.

Though I would probably agree that humanity's general control of our living environment has probably stopped anything big from happening evolution-wise. Then again, have most large animals really evolved much recently?

Define 'recently'.

Of course we are still evolving, it's just that selection pressures are different. Resistances to diseases are still selected for. In addition, there are certain vestigial features that we are losing over time. The one which springs to mind is a vestigial muscle in our arms and legs. Unfortunately I never paid enough attention in anatom to remember it... It's either almost all tendon or absent (in about 10% of people). Wisdom teeth are a similar sort of thing.

Of course we are still evolving, it's just that selection pressures are different. Resistances to diseases are still selected for.

Barely. Modern medicines, cures, and treatments have removed almost all selective pressure for disease resistance from modern societies. Maybe Africans will split off into a hardier subspecies...

In addition, there are certain vestigial features that we are losing over time. The one which springs to mind is a vestigial muscle in our arms and legs. Unfortunately I never paid enough attention in anatom to remember it... It's either almost all tendon or absent (in about 10% of people). Wisdom teeth are a similar sort of thing.

That isn't really evolution; we aren't adapting or experiencing selective change. That's just the slow fading-out a trait that no longer matters - no more evolutionary pressure, no more direction to keep the trait, the trait ceases to be selected for and slowly fades away. General long-term biostatistics, without the natural selection that makes evolution nonrandom.

It isn't added lifespan that's being selected for per se, but rather increased reproductive activity,

Quite right. THe lengthened lifespan would only be a side effect of selecting for better reproductive rates.

I'd like to argue that the average menopause age is greater than 35 though; that would indicate that half of women younger than that are experiencing it. I'd say that the statistical mean would be more like 50, with menopause starting around age 35-40 and ending as late as 60.

Some women go through it quite fast, while others have symptoms linger for years. It would be pretty rare to find a woman of 35 with full blown menopause, However, it does get increasingly unlikely that a woman can achieve pregnancy after that age.

My argument was that the genetic traits that allow a woman to deliver later in life would be shared in common with other aging characteristics, and this would be favoured by mere virtue of the fact that those that could deliver after 35 would out reproduce those that couldnt(of course), and these traits would be passed on. I would imagine that they would have a certain recursive effect from one generation to the next.

Isn't it interesting that we breed cows, pigs, and chickens to bring out the best genetics but allow all types of genetically defective people to breed? It does have one advantage. It keeps the genetic pool large. Because of that, if there comes a time of die-off or great environmental change, there will be a greater variety of genes for nature to draw upon. It's like if you get a pure bred dog you will know its characteristics, but if you get a mutt it will usually be physically and mentally stronger. Kind of makes you wonder, is the US stronger because we are a bunch of mutts? And before that England was the world power. A nation that had been invaded from all directions. Again a bunch of mutts.