# Technology affecting human evolution **URL:** \ **Category:** Factual Questions\ **Created:** [July 19, 2012, 11:04am UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702 "2012-07-19T11:04:00Z")\ **Posts on this page:** 10\ **Page:** 3
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [July 20, 2012, 2:17pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/41 "2012-07-20T14:17:05Z")
> [@Bozuit](#): > > If we are less hairy so we can run then presumably the answer is that other apes don’t run. Not in the same way, anyway. And they, of course, don’t make clothes or even blankets. Don’t pigs use mud as protection from the sun? They’re quite bulky animals so presumably lose heat fairly slowly and don’t need hairs much for warmth. In more temperate places they have more hair. As for why the same thing doesn’t apply to apes, maybe they live in places that get colder overnight, and they’re less bulky anyway. My speculation is getting pretty weak now. But it’s interesting. Mountain gorillas are considerably more hairy than their lowland cousins. ---
**Author:** ![Darwins\_Finch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darwins_finch/32/20304_2.png) [@Darwins\_Finch](https://boards.straightdope.com/u/Darwins_Finch)\ **Post date:** [July 20, 2012, 4:01pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/42 "2012-07-20T16:01:39Z")
> [@md2000](#): > > Like most evolutionary traits, there is no chicken vs. egg situation. [The evolution of sweat glands](http://www.springerlink.com/content/r25946621680811l/): > [@](#): > > However, there is a unique and remarkable thermal eccrine system in humans; we suggest that this system evolved in concert with bipedalism and a smooth hairless skin. So, you are correct that there is no chicken-and-egg situation - because this was not a case of one trait evolving before another. The whole suite of ‘human’ features (trending towards less hair; larger brains; bipedal stance; increased endurance; changing skull shape; etc.) likely evolved in concert - which is, again, exactly what we would expect to see for a neotenous origin for humans. None of these traits were necessarily selected for in and of themselves. Not a Just-So story, but rather a predictable result for an evolutionary pathway. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [July 20, 2012, 6:07pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/43 "2012-07-20T18:07:02Z")
> [@Darwins\_Finch](#): > > So, you are correct that there is no chicken-and-egg situation - because this was not a case of one trait evolving before another. The whole suite of ‘human’ features (trending towards less hair; larger brains; bipedal stance; increased endurance; changing skull shape; etc.) likely evolved in concert - which is, again, exactly what we would expect to see for a neotenous origin for humans. None of these traits were necessarily selected for in and of themselves. Not bipedal stance. That’s neither neotenous nor contemporaneous with the other traits you listed. We don’t know about the hair, of course, but our ancestors were bipedal long before brain expansion shows up in the fossil record. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [July 20, 2012, 6:26pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/44 "2012-07-20T18:26:28Z")
> [@Darwins\_Finch](#): > > [url=“[http://www.springerlink.com/content/r25946621680811l/](http://www.springerlink.com/content/r25946621680811l/)”]Not a Just-So story, but rather a predictable result for an evolutionary pathway. My point being, we can speculate all we want, and point to evidence of A or B or C, and analogies to D, but there is no way to know for sure the facts of evolution. The process of evolution works to emphasize and select for desirable traits, sometimes to the point where they are extreme and exagerrated versions of the original attributes. Neotogeny accounts for one mechanism by which traits can emerge. Something else - selective breeding, basically - encourages it to become a common or dominant trait. > [@John\_Mace](#): > > Not bipedal stance. That’s neither neotenous nor contemporaneous with the other traits you listed. We don’t know about the hair, of course, but our ancestors were bipedal long before brain expansion shows up in the fossil record. Again speculation, but current thought is that we evolved from primates that emerged from the trees occasionally to gather food on the plain. As this became more and more of the activity of this creature, this selected for bipedalism; the best compromise between being able to walk on the ground (possibly carrying things) and also climb trees. We see a bit of this activity in other primates. As bipedalism becomes a more critical proportion of the creature’s activity, then better adaption becomes critical - i.e. the guy that can run faster than his late buddies is the one who makes it back to the trees ahead of the lions. the more often and longer distance you have to do this, the more the selection for simpler, easier bipedal bone and musculature. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [July 20, 2012, 6:35pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/45 "2012-07-20T18:35:01Z")
> [@md2000](#): > > Again speculation, but current thought is that we evolved from primates that emerged from the trees occasionally to gather food on the plain. Not really. That was the “current thought” about 30 years ago. Current thought is that we’re not really sure what was driving bipedalism because we don’t really know where it emerged. We keep finding evidence pushing that date back further in time, and not necessarily in areas with open plains. ---
**Author:** ![jbaker](https://avatars.discourse-cdn.com/v4/letter/j/59ef9b/32.png) [@jbaker](https://boards.straightdope.com/u/jbaker)\ **Post date:** [July 20, 2012, 9:20pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/46 "2012-07-20T21:20:39Z")
> [@Bozuit](#): > > I was thinking recently about how humans could only have evolved to be relatively hairless if they developed clothes at the same time. That got me thinking about other examples of evolution that required some form of technology. We can’t eat much raw meat so fire presumably went hand-in-hand with that adaptation (incidentally, how is it an advantage to be so sensitive to pathogens and parasites? Better absorption of nutrients?) > > Are there any other examples of human evolution that relies on a technology which would now be practically impossible to survive without? There arguably are several such technologies. Contrary to some of the suggestions in this thread, we don’t know why or when humans evolved to have mostly furless skin, nor do we know if that came before, during, or after the development of clothing. However, we do know that survival in areas that have winters is dependent on the use of clothing (or heated buildings). The use of fire and other food preparation technologies was probably important to human evolution, since cooked food is easier to digest. We’re probably dependent on that now as a species, although we can eat many foods raw. I would add midwifery to the list (including its modern version, obstetrics). Human birth is risky without assistance, preferably from a skilled helper. It seems odd to consider them a single technology, but I would also add tools generally. Their use predates modern humans, and they’re required to obtain sufficient food and protect ourselves from danger. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [July 20, 2012, 10:10pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/47 "2012-07-20T22:10:04Z")
I believe that once an animal evolves to a certain intellgence level selective breeding becomes a larger factor in how they evolve. If we take a wild animal and selectively breed it for a specific feature it will change very rapidly. Humans started cooking food so no longer were only disease resistant humans available to breed. Same with hair, less hair may have been more attractive or possibly gone hand in hand with a gene for higher intelligence. I will very often see in dog breeding physical features that will reflect a high percentage of a very specific behavioral trait. Evolution likely stopped being much of a factor in humans 100,000 years ago or more. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [July 21, 2012, 5:38pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/48 "2012-07-21T17:38:40Z")
> [@badger5149](#): > > I believe that once an animal evolves to a certain intellgence level selective breeding becomes a larger factor in how they evolve. Not sure what that really means, but I doubt it’s true in any way I can parse it. > [@](#): > > If we take a wild animal and selectively breed it for a specific feature it will change very rapidly. Well, yeah. That’s the purpose of selective breeding. > [@](#): > > Humans started cooking food so no longer were only disease resistant humans available to breed. Not necessarily. Taking care of sick or injured can be done w/o cooking. > [@](#): > > Evolution likely stopped being much of a factor in humans 100,000 years ago or more. No, that’s not correct. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [July 21, 2012, 9:32pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/49 "2012-07-21T21:32:45Z")
John, look at domestic dogs as opposed to their wild cousins which have barely changed over the years. Humans have selectively bred dogs just as we have selectively bred to one another for specific traits. If we started eating raw carrion a good portion of us would die off. The ones that did not die off would have a gene more resisitant. Once we started cooking food the resistant strains no longer had any reason to dominate geneticaly. A few years back a russian fur farm did an experiemnt with foxes. They selected only for domesticity. Within 5 generation you could no longer recognise these animals as foxes. They were fox like, but not really foxes anymore. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [July 21, 2012, 9:37pm UTC](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702/50 "2012-07-21T21:37:05Z")
> [@badger5149](#): > > John, look at domestic dogs as opposed to their wild cousins which have barely changed over the years. Humans have selectively bred dogs just as we have selectively bred to one another for specific traits. No, we have not “selectively bred” to one another in the way we have selectively bred dogs. > [@](#): > > If we started eating raw carrion a good portion of us would die off. The ones that did not die off would have a gene more resisitant. Once we started cooking food the resistant strains no longer had any reason to dominate geneticaly. People eat raw meat all the time. > [@](#): > > A few years back a russian fur farm did an experiemnt with foxes. They selected only for domesticity. Within 5 generation you could no longer recognise these animals as foxes. They were fox like, but not really foxes anymore. Yes, most of us know about those experiments. They have nothing to do with human mating patterns. [Previous page](https://boards.straightdope.com/t/technology-affecting-human-evolution/628702.md?page=2)