Glossary of 42 Evolution Terms

Learn the correct definitions of evolution terms
A Dictionary in a Library. Getty/Wilfred Y Wong

Looking for a definition related to evolution? Well, look no further! While this is in no way a comprehensive list of all terms you will run into when studying the Theory of Evolution, these are some common words and phrases everyone should know and understand. Many are often misunderstood which leads to an inaccurate understanding of evolution in general. The definitions with links lead to more information about that topic.

Adaptation: changing to fit a niche or survive in an environment

Anatomy: study of the structures of organisms

Artificial Selection: characteristics are selected for by humans

Biogeography: study of how species are distributed across the earth

Biological Species: individuals that can interbreed and produce viable offspring

Catastrophism: changes in species happen because of some quick and often violent natural phenomena

Cladistics: method of classifying species in groups based on ancestral relationships

Cladogram: diagram of how species are related

Coevolution: one species changes in response to the changes of another species that it interacts with, particularly predator/prey relationships

Creationism: belief that a higher power created all life

Darwinism: common term used as a synonym to evolution

Descent With Modification: passing down traits that may change over time

Directional Selection: type of natural selection in which one of the extreme characteristics are favored

Disruptive Selection: type of natural selection that favors both extremes and selects against the average characteristics

Embryology: study of the earliest stages of development of an organism

Endosymbiotic Theory: currently accepted theory as to how cells evolved

Eukaryote: organism made up of cells that have membrane-bound organelles

Evolution: change in populations over time

Fossil Record: all known traces of past life ever found

Fundamental Niche: all available roles an individual may play in an ecosystem

Genetics: study of traits and how they are passed down from generation to generation

Gradualism: changes in species happen slowly over long periods of time

Habitat: area in which an organism lives

Homologous Structures: body parts on different species that are similar and most likely evolved from a common ancestor

Hydrothermal Vents: very hot areas in the ocean where primitive life may have begun

Intelligent Design: belief that a higher power created life and its changes

Macroevolution: changes in populations at the species level, including ancestral relationships

Mass Extinction: an event when large numbers of species die out completely

Microevolution: changes in species at a molecular or gene level

Natural Selection: characteristics that are favorable in an environment are passed down while undesirable characteristics are bred out of the gene pool

Niche: ​role an individual plays in an ecosystem

Panspermia Theory: early life theory that proposes that life came to Earth on meteors from outer space

Phylogeny: study of relative connections between species

Prokaryote: organism made up of the simplest type of cell; has no membrane-bound organelles

Primordial Soup: nickname given to the theory that life started in the oceans from the synthesis of organic molecules

Punctuated Equilibrium: long periods of consistency of a species are interrupted by changes that happen in quick bursts

Realized Niche: actual role an individual plays in an ecosystem

Speciation: the creation of a new species, often from the evolution of another species

Stabilizing Selection: type of natural selection that favors the average of the characteristics

Taxonomy: ​science of classifying and naming organisms

Theory of Evolution: scientific theory about the origins of life on Earth and how it has changed over time

Vestigial Structures: body parts that seem to no longer have a purpose in an organism