Barnacles are organisms that live in aquatic environments and live stationary lives attached to hard surfaces. their feathery appendages catch food as it passes by, making them very successful in tidal waters and within coral reefs. how would scientists best determine the fitness of barnacle populations? counting the number of surviving offspring a population produces placing the barnacles in a new environment to determine survival rates of populations studying the frequency of genes and alleles to determine fitness counting the number of identical offspring produced by a parent population