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all of the changes that have transformed life over an immense time
remains buried by sediments
formation of new species
the time required for one half of the atoms of a radioisotope to emit radiation an decay products
difference among members of a species
consists of all the alleles [different forms of genes] in all the individuals of a population
Distinct form of life
process by which individuals that are better suited to their environment survive and reproduce most successfully; also called survival of the fittest
evolution from a common ancestor of many species adapted to diverse environments
theory where mitochondria and chloroplasts are thought to have evolved from bacteria inside a cell
study of multicellular organisms as they develop from fertilized eggs to fully formed organisms
evolution on the smallest scale—a generation-to-generation change in the frequencies of alleles within a population
separation of populations as a result of geographic change or migration to geographically isolated places
the process of developing character traits to fit in to a new enviroment
remnant of a structure that may have had an important function in a species' ancestors, but has no clear function in the modern species.
species that no longer exist
a group of organisms of the same species populating a given area