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Changes over Time

Cells & Heredity Ch. 5

Adaptation trait that helps an organism survive and reproduce
ancestor similarities in the early development of vertebrates suggest that these animals share a common ______________.
Body fossils also known as preserved remains, are formed when a dead organism is trapped in ice, tar or amber.
branching tree A diagram that shows how scientists think different groups of organisms are related
cast A type of fossil that forms when a mold becomes filled in with minerals that then harden.
Charles Darwin He was a naturalist who studied nature and living things
evolution the gradual change in species over time
extinct A species that does not have any living members
fossil record the millions of fossils that scientists have collected
gradualism a theory proposes that evolution occurs steadily in tiny changes over long periods of time.
homologous structure Body parts that are structurally similar in related species; provide evidence that the structures were inherited from a common ancestor.
how most fossils form organisms that die become buried in sediment
If a group is separated from the rest of the species the main way that a new species forms
mold a type of fossil formed when a shell or other hard part of an organism dissolves, leaving an empty space in the shape of the part
natural selection process by which individuals that are better suited to their environment survive and reproduce most successfully; also called survival of the fittest
overproduction a species creating more offspring that can possibly survive
petrified fossils a fossil formed when minerals replace all or part of an organism
punctuated equilibria the theory that species evolve during short periods of rapid change
radioactive dating A technique used to determine the actual age of a fossil on the basis of the amount of a radioactive element it contains.
relative dating used to determine which of two fossils is older based on the position of fossils in sedimentary rock. The top is younger, the bottom is older.
scientific theory a well-tested concept that explains a wide range of observations
sediments particles of soil and rock
species group of similar organisms that can breed and produce fertile offspring
trace fossils fossils that provide evidence of movements and behaviors of ancient organisms
variation any difference between individuals of the same species.
vestigial structures Body parts that have lost their original function through evolution.
Created by: moschiemann