The male cardinal is bright red. the female is a dull brown. why are the two birds different colors?

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

i hope this : )

c: warm water flows from the western tropical pacific toward south america. that should be the right answer! hope it .