A scientist who studies past life.
The study of past life.
To make note of observations and events, on paper or electronically
Relative Time Scale
The scale of geologic time expressed in terms of officially defined units but without reference to the age of units in years
A sedimentary rock that consists of particles of sand that are cemented together to form a rock
The methods used by scientists to investigate questions, record data, and analyze results
Particles of minerals and rocks that are transported along the Earth's surface and then deposited
Rocks that consist of sedimentary materials
The process of establishing the time equivalence of rocks that exist in areas that are far apart
A stack or sequence of sedimentary rock layers that are exposed at a given place on the Earth
Any evidence of life activities of a plant or animal that lived in the geologic past
Those parts of an experiment that can be changed
Organs or structures in an organism that once served a purpose earlier in the history of the species, but now have no useful function
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