Race is a social construct. It has no useful biological definition nor empirical test and, therefore, is a term simply not used in biology.
Wikipedia wrote:Modern science regards race as a social construct, an identity which is assigned based on rules made by society. While partly based on physical similarities within groups, race does not have an inherent physical or biological meaning.
We're not just making this up, nor adhering to some sort of "political correctness" - I mean, for pity's sake, it's me and tufty, so tell me when are we otherwise unthinking "woke bots" who just virtue signal what's socially acceptable? And, therefore, why would this topic suddenly differ, unless it's simply factually true? - but this is established consensus science.
Please review this Numberphile video, which demonstrates tufty's "mongrel" point by simple mathematical example:
Everyone has two parents. Therefore, four grandparents, 8 great grandparents, 16 great great grandparents. Until we reach the arithmetical conclusion that, following the powers of two, you had over 4 billion ancestors some 32 generations ago.
Except this would initially seem logically impossible, as there were not 4 billion humans alive on the planet some 30 * 32 = 960 (but let's call it a thousand) years ago.
The answer to this conundrum is that we're double counting, triple counting, etc. the same person multiple times. You're related to the same historical person through multiple different lines of descent.
And, in fact, if you continue backwards then you reach the arithmetical conclusion of a historical generation who is either related to everyone alive today (or related to no-one, as their family line died off).
And, as the video covers, finding a shared common ancestor happens far earlier than most people would imagine nor credit.
If you're looking for first generation hybrids, then that happened a very, very, very, very long time ago. Not least because this arithmetic runs continuously throughout Darwin's "Tree of Life". There's no "barrier" between Homo Sapiens and other hominids - we all have Neanderthal DNA, and more recent studies suggest that this is a good thing, because it's now believed that Neanderthal evolved spoken language first. Not Homo Sapiens, but Neanderthal and we inherited it through "cross-breeding", as it were. There's ample evidence of their DNA within ours.
And here's an important note: By the definition of speciation, different species are defined by their sexual incompatibility. By definition, you cannot cross-breed different species (at least not naturally, genetic modification through technology can breach these lines).
You state that race is not important. I would state that it's not even meaningful. This is all continuous - every single individual genetically differs from all other individuals. If you're going to draw arbitrary lines in the sand, then why not that every single human being is a unique genetic individual (even identical twins, due to epigenetics and such). There's 8 billion "races" of human on planet Earth. Or maybe there's 2, or maybe there's 378, or maybe it's all just "lines in the sand" - a social construct - that has no actual biological meaning whatsoever.
Why pick out the handful of genes controlling melanin expression over the far more numerous genes responsible for your unique facial configuration? Or those determining your eye colour over those responsible for the size of your visual cortex, for example?
Why give genes that have overt visual consequences - black skin, red hair, blue eyes, etc. - over, for example, my own genetic claim-to-fame that I have no wisdom teeth. And, no, that's not just that they never developed, they never existed. My gums stop before where any wisdom teeth would have been and there is no space in which they could have ever existed.
Because, you see, earlier hominids had bigger mouths, able to hold more teeth, but as Homo Sapiens developed a smaller mouth, wisdom teeth became a problem. The human mouth doesn't really have room for them - and natural selection was working on removing them, but humanity invented civilisation, dentistry and tooth extraction before it got to complete the job. And as now extract problematic wisdom teeth that they pose no survival threat, then all evolutionary pressure to complete the job has vanished since.
Why pick on someone's levels of "biological sunblock", any more than picking on me for being a post-wisdom-teeth genetic freak?
Because it's easy to see someone's skin colour, but not so easy to count the number of teeth in my mouth?
Melanin is supremely ancient. It developed over 500 million years ago, and is shared by large swathes of the Animal Kingdom. If there were a "black race" and a "white race", then they diverged some 500 million years ago... and we're expected to believe that these separate "races" just so happened to evolve - gene for gene - exactly in parallel with each other, to retain sexual compatibility, ever since?
With nod to Douglas Adams, this is "infinitely improbable" or, in other words, statistically impossible. Or, as tufty put it, "asymptotic to zero".
"Words ought to be a little wild - for they are assaults of thought on the unthinking."
- John Maynard Keynes
Comparisons have been made, perhaps a touch unfairly because as has been pointed the image doesn't catch the full situation, but hey, its not like I like the guy either...
