I always use the money analogy! Its so true and makes the concept of race as a socio-cultural, not biological, reality easier to understand for a lot of people.
Great breakdown of the biology of skin color and how it relates to race. Will be interested to hear more on the historical developments of race. Best 7 minutes I have seen on youtube in a while.
Among "white people" like myself, there are those with the ability to develop protective melanin after controlled exposure to the sun, i.e. we tan. Even among my family, there are those that can't tan, just burn and fade back to pinkish white. When I was young, I could tan to a degree that I could spend hours in the sun without getting a sunburn and obviously so have many other "white people" who live an outdoor life. Yes, in later life, now into my late 70's there has been "pay-back" with pre-cancerous and one instance of a positive diagnosis of melanoma, thankfully removed. The point is, there has been an evolutionary development of certain genetic heritages with the ability to withstand exposure to the sun's harmful effects, at least for the relatively short term. Most likely this ability for early humans was not a problem when they did not live long enough to experience the negative effects. Are the original Australian native aboriginal people lighter when very young, turning darker with exposure to the sun in this category? As well as the Polynesian people? Is there an anthropologist who can answer that? Then there are those "white people" without the ability to develop protective melanin in our skin, as seems to be intermixed within my own familial history. I do agree there is really no such thing as "race." Just a complex array of geographically isolated DNA strains exhibiting varying human characteristics, that have at various times intermixed throughout human migrations. Like dogs, however diverse we may appear, sexual intercourse will more often than not produce perfectly viable babies. We are not as different as horses and donkeys who produce sterile offspring.
Hi Phillip, So a few things, first tanning is a physiological adaptation. In other words, our bodies develop a few strategies that allow us to be a bit more flexible for the environment around us. Another example of this red blood cell changes as a result of high or low altitude. Your body, to some extent produces more red blood cells as you go up higher in elevation to deal with the lower concentration of breathable air. Like tanning some people are better able to do this then others. Plenty of people (and we see it all the time living here in Colorado) really struggle with altitude sickness and take a long time to acclimatize to the different elevation, while others do it with no problem. Melanin does in fact break down with age. (source here: www.ncbi.nlm.nih.gov/pmc/articles/PMC5420599/#:~:text=Melanin%20is%20formed%20under%20the,example%20of%20the%20age%20pigment. ) And becomes less potent over time. It also appears (source here: www.hmpgloballearningnetwork.com/site/thederm/site/cathlab/event/pigmentary-changes-associated-skin-aging#:~:text=Melanin%20may%20increase%20(eg%2C%20solar,of%20hair)%20with%20advancing%20age. ) there are some conditions which may increase melanin with age. These conditions appear to be relatively rare and are more about individual variation, not really across populations. (A more thorough fact check may be needed for that however but I am pretty sure this is the case). A final point here. The more domesticated a species become (and we are basically self-domesticated primates) the more selection changes and variation is free to roam. There is an excellent book on this and how, in fact, it seems we are evolving faster than ever before in history. It's called, The 10,000 year explosion. www.amazon.com/000-Year-Explosion-Civilization-Accelerated/dp/0465020429 Thanks for the very interesting and excellent question. I had to do a bit of reading before I could answer it properly, but honestly those are my favorite questions, because I get to learn something too. And thanks for watching!
Nope, but other environmental factors impact nose shape and hair texture. Humans are also social creatures and so social selection plays a part, but environmental conditions drive certain phenotypes as well, especially in the early days of humans. journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006616
Just as White Europeans and Asians have Neanderthal genetics that sub Saharan Africans do not have. Similarly, Black unmixed sub Saharan Africans have a unique archaic ancestor from 700,000 yrs ago that whites do not have. Perhaps this ancestor contributed some skin color and texture, same as Neanderthal did for the White race.
The history of the human race is far more complicated than that though. There have been endless waves of migration all throughout human history. There is no such thing as an 'unmixed' human and there has never been. Isolated populations are extraordinarily rare in history. The fact of the matter is, humans have gone back and forth from Africa, Australia Asia, and even the Americas countless times. Check out this article: www.sciencemag.org/news/2017/05/theres-no-such-thing-pure-european-or-anyone-else
I always use the money analogy! Its so true and makes the concept of race as a socio-cultural, not biological, reality easier to understand for a lot of people.
An entire lecture on human variation in less that 10 minutes. Quite impressive 👏
Great breakdown of the biology of skin color and how it relates to race. Will be interested to hear more on the historical developments of race. Best 7 minutes I have seen on youtube in a while.
The racists aren't gonna like this knowledge.
Well done my man
What a great presentation on human skin color! I look forward to many more videos. Also, hi class +waves+.
Among "white people" like myself, there are those with the ability to develop protective melanin after controlled exposure to the sun, i.e. we tan. Even among my family, there are those that can't tan, just burn and fade back to pinkish white. When I was young, I could tan to a degree that I could spend hours in the sun without getting a sunburn and obviously so have many other "white people" who live an outdoor life. Yes, in later life, now into my late 70's there has been "pay-back" with pre-cancerous and one instance of a positive diagnosis of melanoma, thankfully removed. The point is, there has been an evolutionary development of certain genetic heritages with the ability to withstand exposure to the sun's harmful effects, at least for the relatively short term. Most likely this ability for early humans was not a problem when they did not live long enough to experience the negative effects. Are the original Australian native aboriginal people lighter when very young, turning darker with exposure to the sun in this category? As well as the Polynesian people? Is there an anthropologist who can answer that? Then there are those "white people" without the ability to develop protective melanin in our skin, as seems to be intermixed within my own familial history. I do agree there is really no such thing as "race." Just a complex array of geographically isolated DNA strains exhibiting varying human characteristics, that have at various times intermixed throughout human migrations. Like dogs, however diverse we may appear, sexual intercourse will more often than not produce perfectly viable babies. We are not as different as horses and donkeys who produce sterile offspring.
Hi Phillip,
So a few things, first tanning is a physiological adaptation. In other words, our bodies develop a few strategies that allow us to be a bit more flexible for the environment around us. Another example of this red blood cell changes as a result of high or low altitude. Your body, to some extent produces more red blood cells as you go up higher in elevation to deal with the lower concentration of breathable air. Like tanning some people are better able to do this then others. Plenty of people (and we see it all the time living here in Colorado) really struggle with altitude sickness and take a long time to acclimatize to the different elevation, while others do it with no problem.
Melanin does in fact break down with age. (source here: www.ncbi.nlm.nih.gov/pmc/articles/PMC5420599/#:~:text=Melanin%20is%20formed%20under%20the,example%20of%20the%20age%20pigment. ) And becomes less potent over time. It also appears (source here: www.hmpgloballearningnetwork.com/site/thederm/site/cathlab/event/pigmentary-changes-associated-skin-aging#:~:text=Melanin%20may%20increase%20(eg%2C%20solar,of%20hair)%20with%20advancing%20age. ) there are some conditions which may increase melanin with age. These conditions appear to be relatively rare and are more about individual variation, not really across populations. (A more thorough fact check may be needed for that however but I am pretty sure this is the case).
A final point here. The more domesticated a species become (and we are basically self-domesticated primates) the more selection changes and variation is free to roam. There is an excellent book on this and how, in fact, it seems we are evolving faster than ever before in history. It's called, The 10,000 year explosion. www.amazon.com/000-Year-Explosion-Civilization-Accelerated/dp/0465020429
Thanks for the very interesting and excellent question. I had to do a bit of reading before I could answer it properly, but honestly those are my favorite questions, because I get to learn something too. And thanks for watching!
@@MichaelKilmanAuthor
Well said!!!
Thanks Michael !
Thanks for making this
Well done!
Does melanin make your nose flat and your hair kinky?
Nope, but other environmental factors impact nose shape and hair texture. Humans are also social creatures and so social selection plays a part, but environmental conditions drive certain phenotypes as well, especially in the early days of humans.
journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006616
Just as White Europeans and Asians have Neanderthal genetics that sub Saharan Africans do not have. Similarly, Black unmixed sub Saharan Africans have a unique archaic ancestor from 700,000 yrs ago that whites do not have. Perhaps this ancestor contributed some skin color and texture, same as Neanderthal did for the White race.
The history of the human race is far more complicated than that though. There have been endless waves of migration all throughout human history. There is no such thing as an 'unmixed' human and there has never been. Isolated populations are extraordinarily rare in history. The fact of the matter is, humans have gone back and forth from Africa, Australia Asia, and even the Americas countless times.
Check out this article:
www.sciencemag.org/news/2017/05/theres-no-such-thing-pure-european-or-anyone-else
best