evolution
a heritable change in the characteristics within a population from one generation to the next; development of new organisms from previous organisms
strata
layers of rock
natural selection
the process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well adapted individual
adaptation
the process of becoming adapted to an environment-being more fit for survival
fitness
in evolutionary theory; a measure of an individual's heredity contribution to the next generation
fossil
the trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock
superposition
a principle that states that younger rocks lie above older rocks if the layers have not been disturbed
relative age
the age of of an object in relation to the ages of other objects
absolute age
the numeric age of of an object or event, often stated in years before the present, as established by an absolute dating process
biogeography
the study of the geographical distribution of living organisms and fossils on Earth
homologous structure
anatomical structures in one species that, compared to other anatomical structures in another species, originated from a single anatomical structure in a common ancestor of the two species
analogous structure
an anatomical structure in one species that is similar in function and appearance but not evolutionary origin, to another anatomical structure
vestigial structure
a structure in an organism that is reduced in size and function and that may have been complete and functional in the organisms ancestors
phylogeny
the evolutionary history of a species or taxonomic group
convergent evolution
the process by which unrelated species become more similar as they adapt to the same kind of environment
divergent evolution
the process by which two or more related but reproductively isolated populations become more and more dissimilar
adaptive radiation
an evolutionary pattern in which many species evolve from a single ancestral species
artificial selection
the selective breeding of organisms(by humans) for specific desirable characteristics
coevolution
the evolution of two or more species that is due to mutual influence, often in a way that makes the relationship more mutually beneficial