I realised that for some reason, I still don’t know this. Why do we have different skin colors, hair textures, eyes or such? Is it just a random thing that happened or are there evolutionary reasons to it?
I realised that for some reason, I still don’t know this. Why do we have different skin colors, hair textures, eyes or such? Is it just a random thing that happened or are there evolutionary reasons to it?
For height and weight, there are links to the climate that the people live in. Typically, hotter climates favor skinny people while colder climates favor more husky people. As for height, my understand is that a dry heat favors taller people as they can take advantage of sweating more than a wet heat.
I think the impact of wealth and access to nutrition and an environment that does not stunt development plays a major role here as well. A good example of this is height in Europe post-industrial revolution and improvements in medicine:
Most notable being a 20cm increase in the Netherlands in just over 100 years as well as changes in places that industrialised quickly like China:
Not to say that geography plays no role but it’s closer to 10cm gap than a 30cm one.