In one species of bird, there are three varieties of feather color. what is this an example of?

How does pregnancy begin? a) a placenta forms in the uterus b) a sperm reaches an egg in the fallopian tubec) the blastocyst differentiates into two cell types d) contractions begin in the uterine wallapex

Eutrophication caused by human nutrient pollution.

Brian has a medical condition called cone dystrophy, which is a disorder of the cone cells in the eye. what symptoms would you expect brian to have? a. inability to see in the dark b. difficulty determining colors c. difficulty determining shapes and outlines d. inability to see in all light conditions