Final answer:
Physical variation between human populations can be attributed to genetic and cultural factors, as well as environmental adaptations and regional preferences.
Step-by-step explanation:
Variation between human populations can be a result of both genetic and cultural factors. Genetic variations can lead to physical differences, such as variations in stature, facial features, and skin, hair, and eye color. Geographic separation between populations can also result in differences in phenotypic variation. For example, warm-blooded mammals near the poles tend to be larger to conserve heat.
Cultural factors, like regional standards of physical attractiveness, also influence physical variation. For instance, regional preferences for certain body morphologies over time can contribute to differences in human phenotypes. Additionally, environmental factors, such as exposure to ultraviolet rays from the sun, can lead to adaptations in skin pigmentation.