Humans have not stopped evolving, and races biologically exist

[ApostateAbe]

Have humans stopped evolving?

At first I thought this line of thinking was merely a way to ridicule the people who think that races do not biologically exist (mainly anthropologists). If races do not exist, then you must believe that humans stopped evolving. But nobody seriously believes that, not even creationists, right?

Wrong. Evolutionary biologists most certainly do not believe it, but I discovered that some prominent scientists who love the public spotlight DO make this claim: David Attenborough (TV anthropologist) and Michio Kaku (TV physicist). Their reasoning is: there is no more natural selection pressures on humans, because survival is now random. Whereas before only the fastest, smartest and strongest humans tended to survive, now anyone can survive.



The scientists with grounding in evolutionary biology have pointed out the primary error: even if survival may be more-or-less random, reproduction starkly is not. Survival is really only a means to the end, the end being reproduction. We absolutely know for certain that some genotypes of humans reproduce more, others less. "Survival of the fittest" is misleading. We should be thinking about natural selection as "reproduction of the sexiest alive."

Even if we were to think purely in terms of survival values, survival is non-random. Sickle-cell anemia of Africa and thalassemia of southern Europe are each diseases that are offshoots of human genetic adaptations to protect against malaria. There is a small subgroup of Africans who are resistant to HIV infection, apparently as a result of genetics. Do we think this will not affect human evolution?

The belief that humans stopped evolving would be appealing to those who deny the biology of race. We can change the word (maybe "races" should be "geographic ancestries" or "ethnicities" or "clines"?), but we absolutely cannot deny the objective evolutionary principle. Evolution would be impossible without the concept of populations within a species adapting to their varying environments by means of differing gene frequencies, a concept still known as "race" in evolutionary biology. See this 2002 article by Ernst Mayr, arguably the most prolific evolutionary biologist: "The Biology of Race and the Concept of Equality."

 

[J842P]

Wow - it doesn't surprise me that Michio Kaku would say that, but David Attenborough? That's disappointing.

 

[fromderinside]

Wow - it doesn't surprise me that Michio Kaku would say that, but David Attenborough? That's disappointing.

Just a simple misunderstanding of what is meant by competition. The primary source of competition pressure on any species is from its own species in the area. That, my friend has definitely not stopped. Its one reason why psychology is not biology.

 

[Malintent]

Humans (and all life) continue to evolve. it can't be helped - save ending reproduction as we know it and a move to a 'perfect replication' cloning system of procreation... then we can say we are out of scope of biological evolution, because we no longer utilize the core mechanics (genetics).
That said, the selection pressures that once applied to our species, no longer does. The direction that evolution takes us is more in our own control, more or less, due to technology (which, in itself, are the fur, teeth, and claws that we evolved and utilized to our success in the food chain).

 

[Kharakov]

 

[fromderinside]

Humans (and all life) continue to evolve. it can't be helped - save ending reproduction as we know it and a move to a 'perfect replication' cloning system of procreation... then we can say we are out of scope of biological evolution, because we no longer utilize the core mechanics (genetics).
That said, the selection pressures that once applied to our species, no longer does. The direction that evolution takes us is more in our own control, more or less, due to technology (which, in itself, are the fur, teeth, and claws that we evolved and utilized to our success in the food chain).

Actually its different approaches by humans to situations and inputs from those of other humans. Within species competition for resources has always been the primary source of selection pressure among most species.

 

[Togo]

Wow - it doesn't surprise me that Michio Kaku would say that, but David Attenborough? That's disappointing.

I'm surprised enough to be sceptical. Does anyone have any references for this?

I don't see the connection between any of those claims and the idea that humans fall into genetically coherant racial groups based on skin colour.

 

[ApostateAbe]

Wow - it doesn't surprise me that Michio Kaku would say that, but David Attenborough? That's disappointing.

I'm surprised enough to be sceptical. Does anyone have any references for this?

I don't see the connection between any of those claims and the idea that humans fall into genetically coherant racial groups based on skin colour.

David Attenborough made the claim to Radio Times here:

http://www.radiotimes.com/news/2013-09-09/david-attenborough-i-dont-ever-want-to-stop-work

Racial groups would NOT be based on skin color alone but on genetics as a whole. Varying races within any species tend toward varying allele frequencies, and humans are no exceptions. In the science of human population genetics, they do not typically call it "race" but instead "ethnicity," "haplogroup," or "ancestry," with the same meaning as "race" used in evolutionary biology. Like races of other species, human races do not have discrete boundaries but fuzzy boundaries.

 

[Jokodo]

Humans have not stopped evolving, and races don't exist.

Seriously, there's no logical connection from "humans are still evolving" to "races (in a sense that would be even recognisable to someone who's familiar only with the common notion of "race") exist". Almost the opposite: the more differences between human populations are due to selection, the less likely they are to coincide with which founder population you came from 10s of thousands of years, and the more likely they are to coincide with what conditions your ancestors have been living in for the last few hundred or thousand years. If there's little gene flow between two populations, the initial differences between their allele frequencies will be relatively stable over time - but much more so for allomorphies that have no adaptive value. A new variant with a high adaptive value will quickly jump from one population to the other and spread in both, though; likewise, a new variant that's adaptive in agricultural societies only (because it contributes to a psychological phenotype that makes it easier for individuals to cope with higher population densities or some such) will quickly jump from African agricultural societies to Western Eurasian agricultural societies to East Asian ones or the other way round while remaining rare in non-agricultural societies of all regions.

 

[rjh01]

David is saying that because 95-99% of babies survive that means natural selection has stopped. He sort of is right. What he has overlooked is the number of children people have. If certain groups have many more children than other groups and these children continue the process then the proportion of the population of these groups increases. I am not talking about certain cultures but features that humans have. For example people who think a certain way or females who have a certain breast size may breed more than others. Thus evolution continues.

 

[bilby]

David is saying that because 95-99% of babies survive that means natural selection has stopped. He sort of is right. What he has overlooked is the number of children people have. If certain groups have many more children than other groups and these children continue the process then the proportion of the population of these groups increases. I am not talking about certain cultures but features that humans have. For example people who think a certain way or females who have a certain breast size may breed more than others. Thus evolution continues.

Exactly. Survival is irrelevant - it is reproduction that counts.

Once upon a time, those who survived to adulthood had a high probability of reproduction; and in such an environment (which still exists in poor parts of the world), survival is a fair proxy for reproduction.

But in the parts of the world today where survival is almost universal, reproduction most certainly is not - fertility rates are below replacement levels in the OECD, and reproduction is patchy - some people have many children, and others have none.

If genetics play any part in determining who does and who does not reproduce - whether due to their dying prior to reproducing, or failing to attract a mate, or choosing not to have children - then evolution marches on.

 

[NobleSavage]

I'm a little tired so I not sure how this is going to sound. Yes, we are still evolving, but what does that have to do with race? When we talk about other animals why don't we use the word race? With pure bred dogs, reproduction is controlled. It seems if you have money you can control your personal reproduction. A woman can buy sperm from a highly qualified donor with no need to be attractive. I'm guessing we are not too far off from designer babies. At some point can we say that we are in control of our evolution?

 

[Jokodo]

I'm a little tired so I not sure how this is going to sound. Yes, we are still evolving, but what does that have to do with race?<snip>

Nothing. ApostateAbe is grasping at straws.

 

[repoman]

What is the difference between breed and race?

 

[rjh01]

What is the difference between breed and race?

In humans there are no breeds or race. The only race is the human race. The genetic differences between regions is minor compared with differences within any one region.

Thanks bilby for your comments.

 

[ApostateAbe]

What is the difference between breed and race?

In humans there are no breeds or race. The only race is the human race. The genetic differences between regions is minor compared with differences within any one region.

Thanks bilby for your comments.

If all humans are a race, then that sounds good, but then "race" loses its biological meaning. We already have a taxon to denote all human beings: species. There is a biological measure of genetic differences between populations, and it is Fst, or Fixation index. It is a value between 0 and 1, with 0 being no difference and 1 being the difference between two different species. The International HapMap Project estimated the Fst among human races to be 0.12. The significance of this value is a matter of opinion, but it most certainly is high enough to count human races as biological races. Any Fst value of statistical significance above 0 would be enough to call human races something. If not "races," then what?

 

[PyramidHead]

In humans there are no breeds or race. The only race is the human race. The genetic differences between regions is minor compared with differences within any one region.

Thanks bilby for your comments.

If all humans are a race, then that sounds good, but then "race" loses its biological meaning. We already have a taxon to denote all human beings: species. There is a biological measure of genetic differences between populations, and it is Fst, or Fixation index. It is a value between 0 and 1, with 0 being no difference and 1 being the difference between two different species. The International HapMap Project estimated the Fst among human races to be 0.12. The significance of this value is a matter of opinion, but it most certainly is high enough to count human races as biological races. Any Fst value of statistical significance above 0 would be enough to call human races something. If not "races," then what?

I believe rjh01's point is that within what we call a "race," there is a larger distribution between 0 and 1 than there is between each "race".

 

[Trodon]

Human evolution accelerated when agriculture began a little over ten thousand years ago in the Mid East. This acceleration happened because of two factors. First, agriculture exerts different population pressures than hunting and gathering. Farmers need to plan ahead to the next growing season. They need to defer gratification. They need to clean up after butchering an animal.

Second, because of agriculture the human population grew. When other factors are equal a large population evolves faster than a small population. This is because there is more room for beneficial mutations to spread.

Civilization began five thousand years ago in the Mid East. Civilization rewards superior intelligence. Intelligent men usually become more prosperous than unintelligent men. Consequently, they have more descendents. In addition, criminal justice systems of civilized countries make it difficult for those with criminal inclinations to reproduce.

This is relevant to racial differences, because agriculture and civilization did not begin everywhere at the same time. They began in different places independently, and spread from there.

During the last century human evolution has reversed somewhat, because there has been somewhat of an inverse relationship between intelligence and prolificacy. Nevertheless, with the advance of computer technology, and the phaseout of programs like Aid to Families with Dependent Children I expect this to end.

 

[Jokodo]

Human evolution accelerated when agriculture began a little over ten thousand years ago in the Mid East. This acceleration happened because of two factors. First, agriculture exerts different population pressures than hunting and gathering. Farmers need to plan ahead to the next growing season. They need to defer gratification. They need to clean up after butchering an animal.

Second, because of agriculture the human population grew. When other factors are equal a large population evolves faster than a small population. This is because there is more room for beneficial mutations to spread.

True, but a larger population also increases pathogen virulence, and thus the lion's share of that faster evolution goes to germ resistance. Under certain parameters, even a variant that increases germ resistance at the cost of decreasing intelligence or dexterity has a good chance of persisting in a dense population, much less so in a sparse one.

Civilization began five thousand years ago in the Mid East. Civilization rewards superior intelligence. Intelligent men usually become more prosperous than unintelligent men.

You really need to define "civilisation" a bit more precisely here. You seem to be shifting between different definitions between the first and second sentences. For the most part of the past 5000 years, for the vast majority of the population, prosperity depended almost entirely on which social class you were born into. Liberal capitalism is a lot younger than 5000 years. By the large, agricultural societies are much more socially stratified, and thus individual success much less merit-based, than hunter-gatherer societies. Unless your definition of "intelligence" includes being born the boyar's first son.

Consequently, they have more descendents. In addition, criminal justice systems of civilized countries make it difficult for those with criminal inclinations to reproduce.

This is relevant to racial differences, because agriculture and civilization did not begin everywhere at the same time. They began in different places independently, and spread from there.

Again, true, but rather irrelevant to anybody who, like ApostateAbe, tries to revive an essentially 19th century notion of races. Agriculture was present in Southern Europe (and independently originated in West Africa) several millennia before it reached Northern Europe. So whatever effects agriculture has could logically not translate to racial features of "Whites" or "Blacks".

 

[ApostateAbe]

If all humans are a race, then that sounds good, but then "race" loses its biological meaning. We already have a taxon to denote all human beings: species. There is a biological measure of genetic differences between populations, and it is Fst, or Fixation index. It is a value between 0 and 1, with 0 being no difference and 1 being the difference between two different species. The International HapMap Project estimated the Fst among human races to be 0.12. The significance of this value is a matter of opinion, but it most certainly is high enough to count human races as biological races. Any Fst value of statistical significance above 0 would be enough to call human races something. If not "races," then what?

I believe rjh01's point is that within what we call a "race," there is a larger distribution between 0 and 1 than there is between each "race".

Yes, Fst actually integrates both values as a ratio.