Which of the following is an example of a phenotype?
a. actual height of an organism
b. the average height of a population
c. the gene that determines an organism's height
d. all of the different heights that an organism can possibly be

Scientists discovered fossils in several layers of the earth you see here. they found fossils of algae, snails, and clams in layer d. given that information, where do you think they found fossil evidence of simple land plants and amphibians?