change in a kind of organism over times: process by which modern organisms have descended from ancient organisms.
well-test explanation that unifies a board range of observations.
preserved remains or evidence of an ancient organism.
selection by human for breeding of useful traits from the natural variation among different organisms.
Struggle for existence
competition among members of a species for food, living space, and the other necessities of life.
ability of an organism to survive and reproduce in its environment.
inherited characteristic that increases an organism chance of survival.
Survival of the fittest
process by which individuals that are better suited to their environment survive and reproduce most successfully; ALSO CALLED NATURAL SELECTION.
Descent with modification
principle that each living species has descended, with changes, from other species over time.
principle that all living things derived from common ancestors.
structures that have different mature forms in different organisms but develop from the same embryonic tissues.
organ that serves no useful function in an organism.