Terms in this set (25)
a break in the geologic record
Variants of particular chemical elements, differs in numbers of nuetrons
process which unstable atoms lose energy by emmiting ionizing particles
amount of time it takes for a substance to decay by half
original isotope that undergoes decay to form daughter
product of decay, remaining nuclide left from radioactive decay
remains traces or imprints of an animal or plant that is preserved in the rock record
study of fossils
study of organisms preserved thorugh fossils
classification of fossils
relationship between fossil organisms and their enviorment
changes in fossils after the death of organism
a fossil preserving all or part of an organism
fossil evidence of some behavioral activity of an organism (ie footprint, borrow, etc)
the fossil remains of excrement of an organism
smooth and rounded polished rocks that were used to aid the breaking down of food by an organism
infilling of voids in the organic material by mineral solutions in fluid passing through the enclosing sediment ( petrified wood)
the preservation of a thin layer of carbon as the only remains of organic material.
original hard organic material is dissolved and replaced by new minerals from solution in fluids passing through the sediment.
sharp decrease in the diversity and abundance of macroscopic life
The extinct organisms are no longer available to compete in the environment so groups that continue through the extinction proliferate.
Fossil group of extinct marine anthropods, Atdabanian stage of earth, 526 million years ago
the isolation of the dead organism from the environment by a protective encasement.