Thanks for all the assist on answering these questions! I was not fully committed to breaking down MHC proteins and how antibodies are made. Immunology isn’t my biomedical subject specialty.

Do you mean antibodies? Antibodies are the proteins that mark antigens (foreign material) as non self and tag it for destruction.

Everyone has a different library of antibodies/immunoglobulins. If you are comparing two people, one may have antibodies to antigens the other does not have (think vaccinated vs non vaccinated unexposed.) The two may also have structurally distinct antibodies but target the same antigen (like two people who get the same illness and develop an immune response and recover. There are also some antibodies that are the same between people, (like between a mother and neonate with antibodies that cross the placenta or are carried in breast milk.)

That’s my simplest explanation.

I can cite my literature review for you, again these are anthropology studies, which is now under biological anthropology or evolutionary biology.

Important point here: a lot of the prevailing ideas about our evolutionary history is based on assumptions, because we don’t have any living specimens of our evolutionary ancestors. How would we ever actually test these ideas with the scientific method.? This research relies a lot of comparisons, correlations, and associations with modern populations as proxy groups understanding that the conclusions may not be 100% accurate. Just because the methods aren’t the epitomized gold standard of science doesn’t mean they are invalid, incorrect, or to be ignored.

Also, anthropology as a discipline started in the 1800: as a “science” to prove racial difference separated humans into distinct species as a way to encourage slavery and as you mentioned eugenics. While that history cannot be erased, papers and research evaluating racial differences in such a way are no longer in circulation and no longer cited or built upon, they have been rejected and dismissed after numerous studies disproved the premises. I did in another post discuss the concept that head size and or brain size is not an indicator of intelligence for this purpose, similarly to why I explained melanin as functional for sun exposure and Vitamin d production, taking them out of the context of eugenics and placing them in the context of physiological function where they belong.

Moving on. Wearing clothing and indoor living are behaviors of modern humans/ homo species, only within the last 300,000 approx. years human evolution as far as the evidence we have extends back 7 million years. Behaviors are studied by cultural anthropologists and archaeologists and are not in my scope of research. However, when we are talking about biological adaptations, that is adaptations and variations in anatomy and physiology, we have to consider a much larger timeline of human evolution. What did we start with and how has it changed.

On body shape-

It’s important to note that shape is not the same as size, it involves relationships in different directions (long AND narrow, short AND broad) your points about the tallest people are more of a size indicator because we don’t have any information about the body shape from just height, are the lean or stout? Anyway

Bergman’s rule and Allen’s rule are the two guiding rule for my statements. They are well documented.

Here are some sources:

Ruff, Christopher B. 1993. Climatic adaptation and hominid evolution: the thermoregulation imperative. Evolutionary Anthropology

*Chris Ruff writes a lot of body morphology and climatic adaptation.

Beals, KL; CL Smith, SM Dodd. 1984. Brain size, cranial morphology, climate, and time machines.

Daniel Lieberman- Story of the Human Body

DeMenocal, PB. 2011. Climate and Human evolution

…. To be continued I’m sleepy.

As the two others have said, absolutely. We have severa morphological features that are different between populations of different climates.

1. Body shape- individuals descended from cold climates are shorter and broader overall, this reduces the body’s surface area to volume ratio which promotes heat conservation. Alternatively, those from hot climates tend to have taller narrower bodies, which increases surface area to volume ratio which is better for evaporative cooling via sweating. Interestingly individuals from areas with monsoon seasons tend to be shorter but narrow overall, to reduce the body’s heat conservation and deal with the difficulties of sweating ineffectiveness. And lastly, populations that tend to be seafaring (Pacific Islanders etc) tend to have a tall yet broad body plan, to shed heat via sweat in the hot temperatures on land, but also cope with the cold breezes of the ocean winds.

2- limb proportions and crania shape follow similar trends to those above. These really refer to Allen’s rule and Bregman’s rules.

3- body hair distribution is larger in colder climates compared to populations in hot climates.

4- skin melanin content- in hot climates with greater radiation from the sun, the skin is more melanated than those climates with less solar radiation. Melanin is protective against solar UV radiation, but prohibitive of melanin production in the absence of sunlight.

5- nasal complex shape- there are climate associations, though the functional explanation has yet to be fully understood. The general thinking goes colder populations tend to have taller narrower nasal airways to promote heat transfer from the nasal mucosa to the cold inspired air to prevent injury to the lungs. This pressure is of no concern in warmer climates so the shapes is short and broad to maximize airflow or inspiratory and expiratory volume during breathing.

Anyhow, yes there are evolutionary adaptations in human populations to cope with the climate they and their ancestors descended from.

Radiological imaging particularly with larger radiation doses are not ordered on potentially pregnant individuals, a pregnancy test may not be offered to a male before imaging putting the offspring at risk. This is also true of some medications like accutane. Though there are reports a new medical recommendation will be including a question for the patients potential to be pregnant to all patients regardless of their sex reported on their file.

Then there are some anatomical differences in the location of certain blood vessels, glands, organs, that aren’t exactly visually apparent, but I can’t say this would be problematic in a surgical setting, maybe problematic in a diagnostic setting.

There can be differences in reported symptoms between sexes, and some medications maybe more effective for a particular sex than another.