# Nature.

**URL:** <https://boards.straightdope.com/t/nature/182200>\
**Category:** Great Debates\
**Created:** [June 16, 2003, 1:01pm UTC](https://boards.straightdope.com/t/nature/182200 "2003-06-16T13:01:49Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![Phlosphr](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@Phlosphr](https://boards.straightdope.com/u/Phlosphr)\
**Post date:** [June 16, 2003, 1:01pm UTC](https://boards.straightdope.com/t/nature/182200/1 "2003-06-16T13:01:49Z")

</div>

Well well well! Phlosphr spent the better part of last night philosophizing with himself and his half asleep wife. You see I have been waiting for the Discovery program “Walking with Cavemen” for a long time and I think the intended affect I was looking for happened full force.  
I was looking for semi-answers - inferences even - into why we are the way we are. I have plenty of knowledge into how we think, what our brain is doing to make those cognitive roadways, and highways n’by-ways connect the way they do. I chose psychology to be the study point in my lifetime. Four years in college studying how humans think and process their thoughts obviously wasn’t enough, so I went back for my master’s. Which gave me a little more insight into why we think and behave the way we do. Then when I decided I wanted more information to base my thinking on I went back and got my PhD to learn more about why people think and behave the way they do. Why some people kill, love, war, or _piss their pants and bark at the moon_.  
Last night’s program on Discovery spurred even more thought about why I like ot build things with my hands, or why I’m the navigator on long trips and my wife isn’t or why she wants a cuddly little kitten and I could careless, I love my big dog. Some of the thoughts I was pondering -\>  
[ul]  
[li]Are we really _that_ civilized right now? If so why?[/li][li]We’ve only been out of the jungle per se, for 10,000 years roughly. But we started walking upright and utilizing tools 3.5 million years ago, roughly. What does that say about or accellerated recent evolution? [/li][li]Are we pretty much just intelligent monkey’s? Where can we go from here? What can we evolve into now? [/li][li]Religion. Why did the royal monkies suddenly decide there had to be someone else, a higher being above themselves? (I have been fascinated with theocratic beliefs and systems of beliefs for a long while, so much so, I teach a new class at the college I instruct at called “The Psychology of Superstition” It delves into the deepest reaches of Irrational behavor, fallacies, Judgement and Decision making, UFO abduction, and inter-human utility.)[/li][li]What does uncovering the past mean about our religious beliefs now, how did humans develope faith?[/ul][/li]  
Whats the straightdope on Nature?

[Added “close list” tag. – MEB]

---

<div class="post-metadata">

**Author:** ![Phlosphr](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@Phlosphr](https://boards.straightdope.com/u/Phlosphr)\
**Post date:** [June 16, 2003, 1:12pm UTC](https://boards.straightdope.com/t/nature/182200/2 "2003-06-16T13:12:35Z")

</div>

I forgot to add the final [/list] sorry those should be bulleted. I wonder if a mod could help?

---

<div class="post-metadata">

**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:** [June 16, 2003, 1:37pm UTC](https://boards.straightdope.com/t/nature/182200/3 "2003-06-16T13:37:27Z")

</div>

> [@](#):
>
> \*Originally posted by Phlosphr \*  
> Last night’s program on Discovery spurred even more thought about why I like ot build things with my hands, or why I’m the navigator on long trips and my wife isn’t or why she wants a cuddly little kitten and I could careless, I love my big dog. Some of the thoughts I was pondering -\>

I watched it, too, and figured someone would start a thread.

> [@](#):
>
> 1. Are we really _that_ civilized right now? If so why?
> 
> 2. We’ve only been out of the jungle per se, for 10,000 years roughly. But we started walking upright and utilizing tools 3.5 million years ago, roughly. What does that say about or accellerated recent evolution?
> 
> 3. Are we pretty much just intelligent monkey’s? Where can we go from here? What can we evolve into now?
> 
> 4. Religion. Why did the royal monkies suddenly decide there had to be someone else, a higher being above themselves? (I have been fascinated with theocratic beliefs and systems of beliefs for a long while, so much so, I teach a new class at the college I instruct at called “The Psychology of Superstition” It delves into the deepest reaches of Irrational behavor, fallacies, Judgement and Decision making, UFO abduction, and inter-human utility.)
> 
> 5. What does uncovering the past mean about our religious beliefs now, how did humans develope faith?
> 
> Whats the straightdope on Nature?

1. “Civilized” is a relative term. We have lots of technology and new social structures, but the forces that shaped our thinking process and emotions had nothing to do with any of that. But we’re very adaptable. That’s the key. We’re able to function pretty well in a wide variety of social structures.

2. Upright: at least 4M yrs. Stone Tools: probably 2.5M yrs. Language is the key. Many anthropoligists now believe that fully articulated language didn’t evolve until perhaps 75k yrs ago. That’s **after** we obtained our current physical appearance. Clearly something big happened about that time frame as the tool kit one finds in fossil sites suddenly expands.

3. Hopefully you learned in your 4 years of college that we are apes, not monkeys. Big difference. Once a species becomes very large in number, as we are, and there are no clear environmental forces acting on it, then it typically does not change much. We’re in that situation now. We may evolve resitance to certain diseases, but there really are no macro-evolutionary pressures on us as a species. Of course, we’re on the verge or being able to completely re-write our genetic makeup, so we may engineer ourselves into an entirely new (or many new) species.

4. Personally, I think it’s a byproduct of our wonderful brain. We’ve evolved to be good at understanding cause and effect. When we see an effect, we try to figure out the cause. If we can’t, then we’re also smart enough to invent one. Lightning? It has to be **caused** by something. Until we actually had the technology to figure out what it was, it made sense to think that someone was up there throwing down lightning bolts. We also tend to “anthropomorphise”. We got this from our evolved ability to “look inside someone elses head and figure out what he is thinking”. It wouldn’t be that unusual that we would use this ability on non-human animals and objects of nature as well.

5. See 4.

---

<div class="post-metadata">

**Author:** ![Antiquarian](https://avatars.discourse-cdn.com/v4/letter/a/c6cbf5/32.png) [@Antiquarian](https://boards.straightdope.com/u/Antiquarian)\
**Post date:** [June 16, 2003, 2:05pm UTC](https://boards.straightdope.com/t/nature/182200/4 "2003-06-16T14:05:54Z")

</div>

> [@](#):
>
> . Are we really that civilized right now? If so why?

My Antropologist buddies would say so. However, if you look at geologic time we are but a fraction of a blink. I personally believe we have along way to go.

**Mr.Mace said** :

> [@](#):
>
> Many anthropoligists now believe that fully articulated language didn’t evolve until perhaps 75k yrs ago. That’s after we obtained our current physical appearance. Clearly something big happened about that time frame as the tool kit one finds in fossil sites suddenly expands.

Fully articulate language is a long shot for 75K years ago. Grunting and bellowing did not end over night. BTW, it was most likely the female who _invented_ articulated speech, as they were the teachers, the ones who taught their young how to forage, pick the red not the green berries. They needed the articulate speech earlier to teach and form words for the increased number of tasks they were doing routinely.  
The Bronze Age - roughly 3500 B.C - is a mile stone in my opinion. Rudimentary tools were going the way of the dodo and more complex systems were in place for higher order thinking.

---

<div class="post-metadata">

**Author:** ![Phlosphr](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@Phlosphr](https://boards.straightdope.com/u/Phlosphr)\
**Post date:** [June 16, 2003, 2:14pm UTC](https://boards.straightdope.com/t/nature/182200/5 "2003-06-16T14:14:16Z")

</div>

Thats 7 years in college **John** , no biggy, I enjoy the nit-pickers on the board. I was just making a point, I know we are apes not monkies, it was more of an editorial monkies…🙂  
Interesting responses all the same **John**.  
Our societal structures revolve around a central core nature with-in us all. Exaulting ourselves in my opinion, above the animal order is an intrinsically human characteristic. The ability to decieve someone of our own species is as well in my opinion.

---

<div class="post-metadata">

**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:** [June 16, 2003, 3:32pm UTC](https://boards.straightdope.com/t/nature/182200/6 "2003-06-16T15:32:42Z")

</div>

> [@](#):
>
> Antique wrote:  
> Fully articulate language is a long shot for 75K years ago. Grunting and bellowing did not end over night. BTW, it was most likely the female who invented articulated speech, as they were the teachers, the ones who taught their young how to forage, pick the red not the green berries. They needed the articulate speech earlier to teach and form words for the increased number of tasks they were doing routinely.  
> The Bronze Age - roughly 3500 B.C - is a mile stone in my opinion. Rudimentary tools were going the way of the dodo and more complex systems were in place for higher order thinking.

A long shor for 75k yrs ago, maybe, but **something** major seems to have happened in our brains around that timeframe and a leap in language ability seems a likely candidate. No one is saying we went from grunts to modern language in one mutation, but perhaps it had something to do with the ability to think symbolically or to think and speak in the future tense.

There is absolutely no evidence that it was “most likely” females who invented fully articulate speach. One could just as easily argue that hunting activites of men were the prime drivers of speach evolution. Both are speculation w/o any data in the fossil record.

The ability to forge bronze tools is just one incremental technology. Writing is probably the most important tool for civilization. That’s a revolutionary invention.

> [@](#):
>
> Phil wrote:  
> The ability to decieve someone of our own species is as well in my opinion.

True. That comes as part of our ability to realize that another individual doesn’t know everything that you know (to "get inside someone else’s head). _Homo sapiens_ children don’t achive this level of thought until about age 5. Chimps seems to have a limitted ability along this lines, but we’re the world champs by a mile.

---

<div class="post-metadata">

**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\
**Post date:** [June 16, 2003, 11:30pm UTC](https://boards.straightdope.com/t/nature/182200/7 "2003-06-16T23:30:46Z")

</div>

> [@](#):
>
> Once a species becomes very large in number, as we are, and there are no clear environmental forces acting on it, then it typically does not change much. We’re in that situation now.

There are huge numbers of environmental forces acting on humans. 1 in every 100 people are going to die of one virus alone (HIV). 10% of people are going to die or be rendered infertile through the actions of one of 10 diseases. 1 in 100 people will die as a direct result of homicide, whether in wartime or more obviously criminal.

Those are clear and acute environmental pressures, far sharper than most other species ever encounter.

---

<div class="post-metadata">

**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:** [June 16, 2003, 11:40pm UTC](https://boards.straightdope.com/t/nature/182200/8 "2003-06-16T23:40:35Z")

</div>

> [@](#):
>
> \*Originally posted by Blake \*  
> There are huge numbers of environmental forces acting on humans. 1 in every 100 people are going to die of one virus alone (HIV). 10% of people are going to die or be rendered infertile through the actions of one of 10 diseases. 1 in 100 people will die as a direct result of homicide, whether in wartime or more obviously criminal.

Where did you get those stats from?

> [@](#):
>
> Those are clear and acute environmental pressures, far sharper than most other species ever encounter.

Unclear that your typical animal is under **less** envirnmental pressure from disease or death by predators.

BTW, you seem to have missed the point where I said that diseases are one area that might be causing evolutionary changes in humans. In fact that was the sentence immediately following the stuff you quoted from me.

---

<div class="post-metadata">

**Author:** ![wolf\_meister](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolf_meister/32/15202_2.png) [@wolf\_meister](https://boards.straightdope.com/u/wolf_meister)\
**Post date:** [June 17, 2003, 12:07am UTC](https://boards.straightdope.com/t/nature/182200/9 "2003-06-17T00:07:45Z")

</div>

Surprised no one said this yet, but is it possible that you could have made your topic title even LESS descriptive? Why didn’t you just call it “things”, “stuff” or even “topic” ?

---

<div class="post-metadata">

**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\
**Post date:** [June 17, 2003, 12:22am UTC](https://boards.straightdope.com/t/nature/182200/10 "2003-06-17T00:22:07Z")

</div>

> [@](#):
>
> Where did you get those stats from?

All over the place. If you’re really intersted, and not just callingme out for the sake of it, I’ll go to the trouble of finding you online refernces.

[quot]Unclear that your typical animal is under less envirnmental pressure from disease or death by predators.  
[/quote]

Of course not. Given that infertility is a disease then every organsim, human or otherwise, is under equal pressure form death and disease and will succumb. Kind of goes with the territory of being alive. I certainly never said otherwise.

And I realise that you siad that disease might bedifent. However homicide is not a disease. Nor are the best methods of avoiding many of these diseases inherently genetic. Behavioural changes can be equally effective. That’s why I consider the comment to be incorrect. Humans remain as subject to environmental pressures as ever.

---

<div class="post-metadata">

**Author:** ![MLS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MLS](https://boards.straightdope.com/u/MLS)\
**Post date:** [June 17, 2003, 1:18am UTC](https://boards.straightdope.com/t/nature/182200/11 "2003-06-17T01:18:29Z")

</div>

> [@](#):
>
> \*Originally posted by John Mace \*  
> \*\*  
> There is absolutely no evidence that it was “most likely” females who invented fully articulate speach. One could just as easily argue that hunting activites of men were the prime drivers of speach evolution. Both are speculation w/o any data in the fossil record.  
> \*\*

True, no hard evidence, nor likely to be any, unless someone invents a time machine. However, you don’t need speech to hunt cooperatively. Many animals do so quite successfully. Lots of animals learn what foods to eat, too, just by imitating their parents, without the need for speech, either.

There’s a great book, [Defending the Cavewoman: And Other Tales of Evolutionary Neurology](http://www.amazon.com/exec/obidos/ASIN/0393048314/qid%3D1055812603/sr%3D11-1/ref%3Dsr%5F11%5F1/104-3150461-8305569) by Harold L. Klawans, which goes into some detail as to why this neurologist believes that speech was transmitted by the females. He is quite convincing.

---

<div class="post-metadata">

**Author:** ![Tyler\_Do\_Urden](https://avatars.discourse-cdn.com/v4/letter/t/3bc359/32.png) [@Tyler\_Do\_Urden](https://boards.straightdope.com/u/Tyler_Do_Urden)\
**Post date:** [June 17, 2003, 2:40am UTC](https://boards.straightdope.com/t/nature/182200/12 "2003-06-17T02:40:33Z")

</div>

[QUOTE]  
\*Originally posted by Phlosphr \*  
\*\*  
[ul]  
[li]We’ve only been out of the jungle per se, for 10,000 years roughly. But we started walking upright and utilizing tools 3.5 million years ago, roughly. What does that say about or accellerated recent evolution? [/li]?[/ul] \*\*

From what I understand it was the development of agriculture in a concerted sense that allowed for our rapid advancement. Biologically we probably haven’t changed a whole lot. Sure, the gene pool has swirled a bit here and there but fundamentally we’re the same as we were 10,000 years ago. Haven’t gotten any smarter, our brains have not gotten any bigger. What has changed is our culture and the type of knowledge we have. Agriculture allowed humans to settle into larger, permanent communities, developing more tools and technology. It also allowed our population to take off. Villages became towns became cities. More complicated methods of communication were needed and developed. Wars were fought between communities and we all know that wars are excellent motivators for technological innovation. Sooner or later, our culture as we know it shows up. So it’s not our “evolution” in a biological sense that advanced rapidly but our technology and culture and population that took off.

I’ll also agree that we don’t really have any major evolutionary pressures on us right now, driving our evolution in a particular direction as a species, besides disease as mentioned above. We have no predators, weather and food are usually not a problem for most of us, there are no physical barriers, and the majority of the species lives to reproductive years.

---

<div class="post-metadata">

**Author:** ![tastycorn](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@tastycorn](https://boards.straightdope.com/u/tastycorn)\
**Post date:** [June 18, 2003, 6:10am UTC](https://boards.straightdope.com/t/nature/182200/13 "2003-06-18T06:10:22Z")

</div>

> [@](#):
>
> There are huge numbers of environmental forces acting on humans. 1 in every 100 people are going to die of one virus alone (HIV). 10% of people are going to die or be rendered infertile through the actions of one of 10 diseases. 1 in 100 people will die as a direct result of homicide, whether in wartime or more obviously criminal.

Might be close to actual numbers, however:

Any environmental forces that do not follow clear genetic traits don’t really have an effect on evolution. If a war kills 1% of the population, but kills it evenly across all genetic variations, then it hasn’t really affected the long term genetic makeup of the entire race. It’s not like the human race as a whole will become less violent because all the violent people went and killed themselves.

Disease also isn’t much of a factor, since any genetic improvement passed on by those naturally immune to the disease is confined solely to not getting that disease, nothing else. The human race as a whole gets a little better immune system, but that’s about it.

If you want a true picture or evolution, you must link genetic traits to birth rates or death rates prior to reproduction.

---

<div class="post-metadata">

**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\
**Post date:** [June 18, 2003, 10:29am UTC](https://boards.straightdope.com/t/nature/182200/14 "2003-06-18T10:29:27Z")

</div>

> [@](#):
>
> Disease also isn’t much of a factor, since any genetic improvement passed on by those naturally immune to the disease is confined solely to not getting that disease, nothing else.

And since you apparently didn’t read the thread, I will repeat: Nor are the best methods of avoiding many of these diseases inherently genetic. Behavioural changes can be equally effective.

Beyond that I’m not sure what you are saying beyond the blindingly obvious. Of course genatic traits can help one avoid death due to homicide or disease.

---

<div class="post-metadata">

**Author:** ![tastycorn](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@tastycorn](https://boards.straightdope.com/u/tastycorn)\
**Post date:** [June 19, 2003, 5:06am UTC](https://boards.straightdope.com/t/nature/182200/15 "2003-06-19T05:06:22Z")

</div>

I might be wrong here, but you seemed to be countering **John Mace** ’s claim that there were no environmental forces that would cause macro-evolutionary changes.

The examples you gave to counter this argument had no relationship to macro-evolution (beyond increased immunity), since they did not follow genetic patterns. What effect, exactly, are behavioral changes supposed to have on macro-evolution without a genetic component?

> [@](#):
>
> Of course genetic(sic) traits can help one avoid death due to homicide

I must have missed the announcement that they found the “shot in the back of the head” gene. 🙂

---

<div class="post-metadata">

**Author:** ![j.c](https://avatars.discourse-cdn.com/v4/letter/j/73ab20/32.png) [@j.c](https://boards.straightdope.com/u/j.c)\
**Post date:** [June 19, 2003, 8:03am UTC](https://boards.straightdope.com/t/nature/182200/16 "2003-06-19T08:03:22Z")

</div>

> [@](#):
>
> 1. Hopefully you learned in your 4 years of college that we are apes, not monkeys.

Speak for yourself, **John Mace**. I am not only a monkey, I am Ray Davies’ famed “monkey woman”! Ray, of course, is a monkey man, and he’s glad I am a monkey woman, too.

Seriously, we don’t know. We don’t know. We just don’t know. We can look at certain people alive today, history, artifacts and make some darn good guesses - and pretty safely rule out some theories (aquatic apes), but we just don’t know.

It’s possible that at some point, early man started following migratory birds around and that was the pivotal point in the march to our current comfortable lives. Perhaps the organization and group effort required to keep an eye on the goose flocks as they were flying north was the first group effort.

Maybe speech was first spread mostly by uncles - except in the gene pools with a lot of redheads. Those types had second-cousins developing their red-head language. We just don’t know.

---

<div class="post-metadata">

**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\
**Post date:** [June 19, 2003, 9:38am UTC](https://boards.straightdope.com/t/nature/182200/17 "2003-06-19T09:38:28Z")

</div>

> [@](#):
>
> The examples you gave to counter this argument had no relationship to macro-evolution (beyond increased immunity), since they did not follow genetic patterns.

Sorry, I have no idea what you mean by this. I only gave examples of environmental pressures. If you are implying that increased survival rates over these pressures can not map onto a genetic pattern then you will need to produce some evidence, since it seems to contradict common sense.

For example it would be quite possible for a genetically determined factor relating to reduced promiscuity to radically decrease an individual’s chance of dying of HIV.

I really don’t understand what the relevance of ‘macroevolutionary changes’ specifically is. Any microevolutionary change has the potential to contribute to speciation, thus any environmental force that promotes evolution is as causative of macroevolutionary change as any other. It seems you are suggesting that there are environmental forces that can cause only macroeveolutionary changes, and those that can only cause microevolutionary. This is not the case.

> [@](#):
>
> I must have missed the announcement that they found the “shot in the back of the head” gene.

You apparently missed where they found the ‘I can run faster’ gene. And the ‘I can see you coming better’ gene. And the ‘I’m quicker on the draw’ gene. All these things have genetic components and all can aid in avoiding death by homicide.

---

<div class="post-metadata">

**Author:** ![Tyler\_Do\_Urden](https://avatars.discourse-cdn.com/v4/letter/t/3bc359/32.png) [@Tyler\_Do\_Urden](https://boards.straightdope.com/u/Tyler_Do_Urden)\
**Post date:** [June 19, 2003, 12:49pm UTC](https://boards.straightdope.com/t/nature/182200/18 "2003-06-19T12:49:25Z")

</div>

**Blake** I believe you may be taking too broad a view of genetics. First, the genetic link to behaviors, especially those as complex as promiscuity, is very complicated. While there is evidence of some genetic influence of behaviors that may increase your mortality, the relationship is sketchy at best and is most likely controlled by a plethora of different genes, as well as environmental factors. Same thing goes for the “I can run faster” and the “I can see you coming” etc. While there is genetic influence, many genes are involved, not even counting real world experience.

Hence, since the system is so complex, it is difficult for anything to act as a directed selective force. You cannot select for just one gene but a myriad of interacting genetic factors. You miss one, it could all be for naught. Plus, you cannot select for environmental factors.

Furthermore, I don’t think that any of these factors, excluding disease, have a great enough effect to be truly selective. Homicide doesn’t even come close, nor does risk taking behavior such as sky diving etc. Thus, even if there was a simple genetic factor to be selected for, it wouldn’t affect the population as whole.

---

<div class="post-metadata">

**Author:** ![Dogface](https://avatars.discourse-cdn.com/v4/letter/d/9d8465/32.png) [@Dogface](https://boards.straightdope.com/u/Dogface)\
**Post date:** [June 19, 2003, 2:58pm UTC](https://boards.straightdope.com/t/nature/182200/19 "2003-06-19T14:58:47Z")

</div>

> [@](#):
>
> \*Originally posted by Blake \*  
> \*\*There are huge numbers of environmental forces acting on humans. 1 in every 100 people are going to die of one virus alone (HIV) \*\*

Of course, this does not mean that 2.5 million US citizens will die this year of HIV. There comes a point where a statistic becomes meaningless.

---

<div class="post-metadata">

**Author:** ![Dogface](https://avatars.discourse-cdn.com/v4/letter/d/9d8465/32.png) [@Dogface](https://boards.straightdope.com/u/Dogface)\
**Post date:** [June 19, 2003, 3:31pm UTC](https://boards.straightdope.com/t/nature/182200/20 "2003-06-19T15:31:36Z")

</div>

> [@](#):
>
> \*Originally posted by Blake \*  
> \*\*For example it would be quite possible for a genetically determined factor relating to reduced promiscuity to radically decrease an individual’s chance of dying of HIV. \*\*

Alternatively, a mutation in the _CCR5_ gene, which has no relationship at all to behavior, can confer very strong resistance to HIV. It is projected that about 10% of the British population is at least heterozygous for this mutation.

Indeed, the _CCR5-D32_ and similar mutations are much more likely to have an effect on the spread of HIV than would be any sort of “behavior-related” genetic mutation. The immune mutation has a direct effect on the infection. Genetic effects on behavior are far more indirect and far less strong.

[Next page](https://boards.straightdope.com/t/nature/182200.md?page=2)
