The preserved remains or traces of an organism that lived in the past.
Any difference between individuals of the same species.
Process by which individuals that are better suited to their environment survive and reproduce most successfully.
A gradual change in a species over time.
A technique used to determine which of two fossils is older.
A technique used to determine the actual age of a fossil.
A trait that helps an organism survive and reproduce.
English natural scientist who formulated a theory of evolution by natural selection.
Small, solid pieces of material that come from rocks or living things.
Occurs when some members of a species become cut off from the rest of the species.
Body parts that are structurally similar in related species.