Answer:
about skin coloration:
Regarding these modifications, we can say that it influences not only the knowledge of evolution but also on the development of strategies for the management of many diseases, so we know that these changes are not produced by a single agent and factors such as Melanin, a substance produced by melanocytes and which gives the tint to each tone, also includes influences such as exposure to sunlight, both in frequency and geographical area from which it is made. Keratin is also found as its own dermal factor. According to this, there has been an adaptation of the phenotype of each individual mainly to the UV environmental factor that can make changes and modify skin tone.
About lactose tolerance:
It is known that historically, after childhood for many people it was very difficult to continue consuming milk, because the enzyme lactase was not found in them and lactose digestion became very difficult, nowadays it is believed that the weather has influenced to improve digestion
About the body shape:
The inherited factors are very important, from the different habitats of our ancestors, which for reasons of hunting, solar exposure, type of food, were being inherited, today it is known that there are 3 main forms of body types including the endomorph, ectomorph and mesomorph, the main advantages depending on where the individual lives will adapt to persist in the next generation, as well as to use new ways of obtaining food can modify it
