: the existence of two different forms (as of color or size) of a species especially in the same population
: the existence of a part (such as leaves of a plant) in two different forms
Recent Examples on the Web Humans lie closer to gibbons on the dimorphism spectrum: human males can be up to 20 percent more massive, on average, than females. —Blake Edgar, Scientific American, 1 Oct. 2016 Humans seem to lay between other ape lineages in terms of physical dimorphism. —Razib Khan, Discover Magazine, 6 Jan. 2012 In particular, dimorphism between the sexes, and the importance of selection in mate choice. —Razib Khan, Discover Magazine, 23 June 2013 Not to mention that dimorphism isn’t necessarily stark. —Riley Black, Discover Magazine, 10 Nov. 2020 But the general behavioral point is rooted in realities of anatomy and life-history; in many dioecious species males and females exhibit a great deal of biological and behavioral dimorphism. —Razib Khan, Discover Magazine, 31 Mar. 2010 The reason why honeybees use such a sophisticated and intricate mechanism to regulate the queen–worker dimorphism is a puzzle. —Chao Yan, Scientific American, 17 June 2020 Hunt believes knowledge of the adverse effects of dimorphism could help us better predict and prepare for species endangerment down the road. —Ryan P. Smith, Smithsonian, 16 Apr. 2018 Phylogenetic analyses of sexual selection and sexual size dimorphism in pinnipeds. —Darren Naish, Scientific American Blog Network, 3 June 2017 See More
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'dimorphism.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
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