remnant of a structure that may have had an important function in a species' ancestors, but has no clear function in the modern species
body parts that are structurally similar in related species; provide evidence that the structures were inherited from a common ancestor.
the remains (or an impression) of a plant or animal that existed in a past geological age and that has been excavated from the soil
a theory that explains how random changes in genetic material and competition for scarce resources cause species to change gradually
process by which individuals that are better suited to their environment survive and reproduce most successfully; also called survival of the fittest
Process through which early prokaryotic cells are thought to have engulfed other, smaller cells and eventually incorporated them as organelles (such as mitochondria and chloroplasts); these cells evolved into modern-day eukaryotes.
The comparison of stages of embryo development that shows how the embryos of different groups resemble each other at particular stages. Similarities indicate groups may share a common ancestor
similarities at molecular level that indicate evolution from a common ancestor or interrelated group of common ancestors; DNA or protein sequences for genes with low mutation rates are compared, usually cytochrome c
French naturalist who proposed that evolution resulted from the inheritance of acquired characteristics
English natural scientist who formulated a theory of evolution by natural selection
differential reproductive success
the tendency of some individuals to have greater reproductive success and produce more living offspring than other individuals in a population