Are human beings still evolving in response to any recognizable factors?

True, but the factor that plays the biggest part in deciding to delay parenthood is female education. To my mind, the education of women holds the key to lowering birth rates in developing countries.

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It may already be widely known that it is kinky hair that protects best from sun on savannahs of Africa or elsewhere.

I love looking at why body part exist in relation to various animals and other biologicals. So not intending to distract from the running specific aspect, I wanted to mention what I read some years back regarding human male having one of the larger sex organs for body size.

Been years since I read that. It may have been the book “Sex On the Brain” by woman named Blum. Again I forget exactly or if more info exists in those regards.

A cats tail --male and female-- is used for balance when falling or running.

To run or not to run, is that the question. :thinking:

Independent of the intelligence factor, more infants with big heads are probably surviving childbirth because of medical research and lawyer pressure to perform c sections. I am not aware of any studies on it but I wonder if eventually c sections and modern medicine will change the growth curve …there are so many that deliver this way now (though there has been a backlash towards some “natural birth,” hopefully the right practioners move to c section when the baby’s life is on danger)

This book was required reading way back at the turn of the millennium in the only college biology course I took, Human Evolutionary Biology (taught in part by the now-disgraced Marc Hauser).

The book rocked my world. I had no way at all to fit it into my worldview at the time. None.

Good stuff!

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(also for @T_aquaticus and @Jay313)

The sexualized, peaceful bonobo tale is a myth. See the discussion of the faux-nobo here.

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What do you know…as more with big heads survive and pelvises do not expand to accommodate them, this paper estimates a 10-20% increase in problems with birth due to head size.

So primatologist Frans de Waal just made up a bunch of b.s.?

I don’t pretend to be an expert on this, but I did link to an article by experts. Did you read it?

I didn’t read it start to finish, but I did see this:

So what went wrong?

Observing bonobos in their remote forest habitat is very difficult. For this reason, writes Saxon, early research frequently focused on captive bonobos and artificial feeding sites. These groups were often quite small, had many sub-adult bonobos, and, of course, the captive bonobos were not living in natural settings. Juvenile and adolescent bonobos turned out to be far more sexually inclined than adults are. Rich concentrated food stores (artificial feeding sites) induce near-panic in bonobo groups and this provokes sexual behavior. It is not representative of typical bonobo life in the African wild.

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Were you at Harvard, Andrew? Interesting!

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Yes, but note that the appropriate spelling is Hahvahd… :slight_smile:

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I followed the link and found a blog post written by a non-scholar, talking about a book by an “independent researcher and author.” I did not find what I would consider to be “an article by experts.” @beaglelady is right to point you (and us) back to Frans de Waal.

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I meant to say, “an article summarizing work by experts.” A careless shortening on my part. I am well aware of the habitual massacring of actual science by pop science journalists.

Still, I should have dug further to see that the author summarized is an “independent researcher and author.”

Thanks for the corrective note. I’ll have to dig deeper and see how her work has been received in the wider scientific community.

Having now seen the cover of the book being summarized in my article, I’m thoroughly embarrassed that I didn’t investigate further. Shame on me!

That said, the claims are not entirely without merit, it seems.

Zanna Clay of the U of Birmingham, who has published with de Waal, also detracts from the stereotypical view. Emphasis in the quotation below is mine; it points to aggression in bonobos. They do not war as chimps and humans do, but they are far from peaceful. [Edited for accuracy.]

This is all true, but the public fascination with these behaviours has given rise to a view of bonobos that is a little extreme, says Zanna Clay of the University of Birmingham in the UK, who has spent years studying wild bonobos. “There is this perception that they have sex all the time, that they are like nymphomaniacs.”

The reality is more nuanced. The frequency of copulation in bonobos is not as high as most people assume, she says. “In terms of reproduction they are not more sexually active than chimps.”

The genital rubbing and touching is very common, but it only happens in very specific contexts, often ones that are not obviously sexual.

“People think they just do it for fun but it’s not really to do with that. It’s to do with uncertain social situations,” she says, summarizing the conclusions she and de Waal came to in a paper published in the journal Behaviour in 2014.

For instance, when a group arrives at a new feeding tree, there is tension over who is going to make the richest pickings. “The females will have lots of genital contact with each other and that will relieve the apprehension of this feeding competition,” says Clay. “Once they are calm they can actually feed together in the tree and be quite peaceful.”

Females will also often use genital rubbing to defuse tension between two rival groups, avoiding the kinds of violence seen in chimp wars. But this does not mean that bonobos are incapable of aggression.

“One of the reasons they have this genital touching is because they need to relieve tension after they’ve had fights.”

Things can get particularly nasty in zoos, where the artificial set-up can let females assume more power than they normally would in the wild. These super-dominant females can be pretty violent towards males, says Clay.

“There are lots of males in zoos that are missing digits. There’s a male bonobo that’s actually missing the tip of his penis because the female has bitten it off,” she says. “This isn’t quite [in line] with the stereotype of them being peaceful.”

My impression is that you found a cultural spat with relatively little scientific impact. The author (Lynn Saxon) seems to have made her name by attempting to rebut Sex at Dawn, a speculative lay-level book from 2010 that causes good people to squirm because it’s in part about promiscuity. It is surely the case that this dispute, about whether “we” are or should be monogamous, has spawned the misuse of science by partisans on both sides of the… “debate.”

What remains undisputed is the dramatic difference between bonobos and chimps. This difference is relevant anytime human culture or behavior is examined in an evolutionary context. Our closest living relatives are chimps and bonobos, which gives every propagandist or partisan a choice: to choose one or the other (and thereby mislead their audience) or to acknowledge the incredibly interesting complexity that the chimp/bonobo/human tree exhibits.

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No, I disagree. Huge kudos for acknowledging an error. No more shame.

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It’s funny noticing the anxiety one can feel watching the little “sfmatheson replying…” :grinning:

I guess that means I’m not an alpha male…

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It was also in BBC. I thought it sounded familiar…BBC Earth | Home

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That’s the same piece that @AMWolfe linked above. I think it’s easy to see that the primatologists are trying to counter over-interpretation of their work. This is, IMO, different from claiming that the bonobo’s distinctness is a “myth.” The BBC piece doesn’t say that, because no primatologist says that. The upshot is that someone who points at chimp warfare as somehow more relevant to human evolution than bonobo genital-rubbing is someone cherry-picking data to tell a misleading story. At least that person will be way ahead of the hapless Jordan Peterson, who chose lobsters. :laughing:

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Are human beings still evolving?

Yes, faster than ever. (though some stretching of what is meant by evolution is involved in arriving at this conclusion)

Genetically we are only seeing a great increase of genetic diversity as a result of the community protecting and supporting the survival of the individuals. But it is a mistake to think this represents an end or stalling out in the evolutionary process. The opposite is the case.

  1. The real driving force of evolution is not selection, but variation.
  2. In addition to the evolution of individuals there is also the evolution of communities. And while the first requires selection, the latter thrives on diversity because it serves the development of specialization, which in turn enables the development of production, transportation, and communication technologies. This has happened at least twice before, first with the development of eukaryotic cells and second with the development of multi-cellular organisms.
  3. But the greatest leaps forward in the evolutionary process is the advancement of information storage and transmission, such as when life on this planet learned to utilize DNA and RNA molecules. Human civilization has improved upon this with the development of language and other communication media. As a result we no longer suffer from the limitation of “no inheritance of acquired characteristics.” Now we learn things in the matter of years and radically transform the nature of our existence in mere decades.

What are the factors we are evolving in response to?

The environmental challenges are still there, including disease, disasters, waste management. In addition there are all kinds of internal challenges from social conflict and adjusting to the changes in life largely due to our own advances. But now our range of responses to these challenges are greatly increased to include legal and technological solutions. The DNA and biological solutions are much too slow to be of much value by comparison (not by its own learning/evolutionary methods anyway).

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Thank your for your input, @sfmatheson . I think it was Abraham Lincoln who said that you can’t trust everything you read on the internet.

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