Evolution

Evolution

A process that results in changes in the genetic material of a population over time

Natural Selection

The process where organisms with traits better suited to their environment tend to survive and reproduce more successfully, leading to those traits becoming more common in a population over generations.

Law of Superposition

The lower a rock layer is the older it is. the higher the rock layer, the younger it is.

Index fossil

a fossil that is useful for dating and correlating the strata in which it is found.

vestigial structure

Structures that have no apparent function and appear to be residual parts from a past ancestor

Anatomical structure

A specific identifiable part of an organisms body ranging from microscopic components like cells to large scale organs and organ systems.

Embryo

An unborn or unhatched offspring in the process of development

Relative age

The geologic age of a fossil organism rock, feature, or event defined relative to other organisms, rocks, or features

Absolute age

The numeric age of a layer of rocks or fossils.

Comparative embryology

The comparison of embryo development across species

Punctuated equilibrium

The hypothesis that evolutionary development is marked by isolated episodes of rapid speciation between long periods of little or no change

Geologic time scale

A representation of time based on the rock record of earth