Here's the excerpt.
Guppies are small, tropical freshwater fish that display wide variation in coloration. Some have bright splotches of blue, red, and orange, while others are quite drab and dull. Research has shown that females prefer to mate with brightly colored males; however, this trait makes them more likely to be seen. Guppies, like all species, must be able to both survive and reproduce in order to avoid extinction
One process that is responsible for the variations in coloration observed in guppies is that how females mate with male guppies. They prefer to mate with brightly colored males.