Glossary of Terms Regarding Evolution

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