Why are embryos more useful than adults for showing evolutionary relationships among organism? choose one
1.) embryos may have features that are not found in adults
2.) adults may have mutations that are not found in embryos
3.) evolutionary relationships are more easily observed in simpler organisms
4.) related organisms always appear identical in a embryonic stages

answer; i believe the answer is (polygenic inheritance;

answer: accepted answer: aquatic animals use the oxygen dissolved in water to carry out respiration. since the amount of dissolved oxygen in water is low as compared to the amount of oxygen in the air, therefore the rate of breathing in aquatic animals is much faster than it is in terrestrial animals.

explanation:

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.