Which of the following is not a central theme of biology?

Many kangaroo rats live in the sonoran desert of the southwestern united states. they have a variety of adaptations for living in the desert. under which circumstance would the kangaroo rats of the sonoran desert be most likely to develop new adaptations by natural selection?

What causes darkening of the skin as melanin production increases

Two critical interventions to turn around the opioid crises are: