Image of cross-country champion Lornah Kiplagat

Question 1
Below is an image of cross-country champion Lornah Kiplagat. She has a body type often seen of Nilotic peoples: tall, long-limbed, and slender. Why is this body type adapted for warm locations?

What is an example of a short-term acclimatization, or acclimatory adjustment, other than tanning?

What is an example of a genetic adaptation to a specific environmental condition other than skin color?