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Biology Ch 15.2
Ch.15 vocab
Term | Definition |
---|---|
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 an object in relation to the ages of other objects |
Absolute age | the numeric age of an object or event, often stated in years before the present, as established by an absolute dating process, such as radiometric dating |
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 in evolutionary origin, to another anatomical structure in another species |
Vestigial structure | the structure in an organism that is reduced in size and function and that may have been complete and functional |
Phylogeny | the evolutionary history of a species or taxonomic group; the relationships by ancestry among species or taxonomic groups |