Race

Although Charles Darwin rarely discussed human races, his theories were incredibly influential on biological anthropology. Darwin argues that the existence of race cannot be denied, even if scientists disagree on how many races constitute the human species (source):

There is, however, no doubt that the various races, when carefully compared and measured, differ much from each other, as in the texture of the hair, the relative proportions of all parts of the body, the capacity of the lungs, the form and capacity of the skull, and even in the convolutions of the brain. But it would be an endless task to specify the numerous points of difference. The races differ also in constitution, in acclimatisation and in liability to certain diseases. Their mental characteristics are likewise very distinct; chiefly as it would appear in their emotional, but partly in their intellectual faculties.

Well, what is race? Races are groups of human beings distinguished by patterns of visible physical features, groups whose members are linked by a common ancestry peculiar to members of the group, and which originate from a distinctive geographic location.

Criticism

"Evolution Takes A Long Time!"

Well, it usually does, but there is no universal amount of time it can take. The timeline of speciation depends on a variety of factors and can vary greatly. In a Soviet experiment, a group of silver foxes, were domesticated via selective breeding within just 10 generations. In addition, the selection, intended exclusively for this behavioral trait, led to population changes in physical traits such as floppy ears (source).

Modern humans have existed for atleast 200,000 years ago (source). By comparison, here is how long ago the subspecies of various other animals diverged from each other:

We know that humans evolved regional differences in skin color and adult lactose tolerance, so we know for a fact that there has been some divergent evolution going on. It isn’t immediately obvious that there “isn’t enough time” for humans to form subspecies, especially since punctuated equilibrium and introgression provide mechanisms for fast evolution.

What are the chances that evolution ended at the neck given that different populations evolved in different regions with varied climates, diseases, obstacles, different plants & wildlife, etc. What are the odds that despite almost ~40% of the genome influencing cognition (source, source 2) there would be no difference in specific regions of the genome connected to cognition? What are the odds that despite population variances in Neanderthal ancestry (source), which is associated with skull shape (source) , all human populations have exactly the same intelligence?

We shouldn't be surprised that, as it turns out, racial differences in terms of genes involved in the brain are larger than the racial differences in terms of genes involved in physical traits like skin color or hair texture, especially given that Human evolution has sped up by a factor of 100 in the past 5000 years (source) and genes involved in the brain are overrepresented among those having recently undergone selection (source).

"99.9% the Same!"

One popular argument used against the possibility of races in humans is that “humans are 99.9% the same”, this claim was first made by Craig Venter in 2000 (source). However, he was involved in Levy et al. (2007), which finds that humans are 99.5% the same. Despite this, it is still a popular talking point that we are 99.9% the same (source).

This figure is based on base pair similarity, (source), so a .5% difference is obviously significant. To put that in perspective, the difference between someone with and without the disease sickle cell anemia is a single SNP (source) and humans are 98.76% similar to chimpanzees (source).

We can also just look at heterozygosity, which is essentially the degree of genetic diversity in a population. Human heterozygosity seems to be atleast .7 to .776 [source, source 2 & source 3] which is not only well within the normal bounds for other species but even higher than many other species.

Lewontin's Fallacy or "More Variation Within Than Between"

The fixation index (FSt) is the proportion of the total genetic variation of a subpopulation (s) relative to the total genetic variation of the total population (t). An Fst rating of zero means total sharing of genetic material. The subpopulations are genetically identical, like clones, for example. An Fst rating of one means that there is no sharing whatsoever.

Richard Lewontin was the first to measure human FSt, and he found it to be 6.3% Based on this finding, Lewontin declared that categorizing humans racially has no “genetic or taxonomic significance”. He never explains why this number is too low, he just say it is (source).

To claim that a “low” Fst rating invalidates humanity’s distinct subspecies would require us to declare countless other subspecies as “biologically invalid.”

Clines, Not Races

Clines refer to a pattern of continuous variation in a trait or characteristic of a population. For some reason, it is said by race deniers that this concept replaces race, but these do not contradict each other.

Let's apply this to sex for example, there are two sexes, and there are traits associated with both of the sexes, which we refer to as primary and secondary sex characteristics. Men are on average taller than women, but there are obviously short men and tall women. Does this mean sex does not exist and that sex differences dont exist?

James Huxley, the originator of the term cline did not see clines and races as antithetical. This argument is simply a category error.