What must be present for natural selection to occur?

Ausable water source is one that can be used by humans for drinking or agriculture. identify the water reservoirs as usable or unusable based on their current state. oceans rivers glaciers freshwater lakes groundwater

The allele for curly hair is incompletely dominant. if a mother is homozygous for curly hair and the father is homozygous for straight hair, what percentage of the offspring will exhibit characteristics of both parents? 25 percent 50 percent 75 percent 100 percent

Describe characteristics of a good respitory surface