an organism that and must get energy by eating other organisms or organic matter
. heterotroph
an organism that , usually using sunlight (photosynthesis)
autotroph
When a species completely disappears and no longer exists.
Extinction
Differences in traits among individuals of the same species.
Variation
A change in DNA that can create new traits in organisms.
Mutation
An early form of a species from which later species evolved.
Ancestor
body parts that are the same or similar in different species
Homologous structures
body parts that are useless or left over from a previous ancestor in which they were useful
Vestigial structures