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Copes rule

Cope's rule In 1871, the American palaeontologist Edward Drinker Cope (1840–97) noted a phylogenetic trend towards increased body size in many animal groups, including mammals, reptiles, arthropods, and molluscs. This came to be known as Cope's rule. It remained unchallenged until a study of more than 1000 insect species in 1996 and was finally disproved in 1997, by a study in which David Jablonski made more than 6000 measurements on 1086 species of Late Cretaceous fossil molluscs spanning 16 million years and found that as many lines led to decreased size as to increased size. Evolutionary lineages show no overall tendency to greater size, but if the extant survivor happens to be larger than its immediate ancestor (e.g. the horse) this coincidence appears to validate Cope's rule.

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"Copes rule." A Dictionary of Ecology. . Encyclopedia.com. 14 Dec. 2017 <http://www.encyclopedia.com>.

"Copes rule." A Dictionary of Ecology. . Encyclopedia.com. (December 14, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/copes-rule-1

"Copes rule." A Dictionary of Ecology. . Retrieved December 14, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/copes-rule-1

Copes rule

Cope's rule In 1871, the American palaeontologist Edward Drinker Cope (1840–97) noted a phylogenetic trend towards increased body size in many animal groups, including mammals, reptiles, arthropods, and molluscs. This came to be known as Cope's rule. It remained unchallenged until a study of more than 1000 insect species in 1996 and was finally disproved in 1997, by a study in which David Jablonski made more than 6000 measurements on 1086 species of Late Cretaceous fossil molluscs spanning 16 million years and found as many lines led to decreased size as increased. Evolutionary lineages show no overall tendency to greater size, but if the extant survivor happens to be larger than its immediate ancestor (e.g. the horse) this coincidence appears to validate Cope's rule.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Copes rule." A Dictionary of Earth Sciences. . Encyclopedia.com. 14 Dec. 2017 <http://www.encyclopedia.com>.

"Copes rule." A Dictionary of Earth Sciences. . Encyclopedia.com. (December 14, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/copes-rule

"Copes rule." A Dictionary of Earth Sciences. . Retrieved December 14, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/copes-rule