Glossary of Terms Regarding Evolution

Following are definitions of common terms referring to the Theory of Evolution that everyone should know and understand, though this is by no means a comprehensive list. Many of the terms are often misunderstood, which can lead to an inaccurate understanding of evolution. The links lead to more information on the topic: Adaptation: Changing to fit a niche or survive in an environment Anatomy: Study of the structures of organisms Artificial Selection: Characteristics selected 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 that happen because of 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 changing in response to changes in another species that it interacts with, particularly predator/prey relationships Creationism: Belief that a higher power created all life Darwinism: Term commonly used as a synonym for evolution Descent With Modification: Passing down traits that might change over time Directional Selection: Type of natural selection in which an extreme characteristic is 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 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 can play in an ecosystem Genetics: Study of traits and how they are passed down from generation to generation Gradualism: Changes in species that happen 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 might 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: Event in which large numbers of species died out completely Microevolution: Changes in species at a molecular or gene level Natural Selection: Characteristics that are favorable in an environment and are passed down while undesirable characteristics are bred out of the gene pool Niche: ​Role an individual plays in an ecosystem Organelle:Â  Subunit within a cell that has a specific function Panspermia Theory: Early theory proposing 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 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 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