title: Handicap principle implies emergence of dimorphic ornaments.
abstract: Species spanning the animal kingdom have evolved extravagant and costly ornaments to attract mating partners. Zahavi's handicap principle offers an elegant explanation for this: ornaments signal individual quality, and must be costly to ensure honest signalling, making mate selection more efficient. Here, we incorporate the assumptions of the handicap principle into a mathematical model and show that they are sufficient to explain the heretofore puzzling observation of bimodally distributed ornament sizes in a variety of species.
authors.affiliation: Department of Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, IL 60208, USA sclifton@u.northwestern.edu.
authors.forename: Sara M
authors.identifier: 0000-0001-5949-068X
authors.initials: SM
authors.lastname: Clifton
authors.affiliation: Northwestern Institute for Complex Systems, Northwestern University, Evanston, IL 60208, USA.|Division of Biostatistics, Northwestern University, Chicago, IL 60611, USA.
authors.forename: Rosemary I
authors.identifier: 0000-0001-9668-9866
authors.initials: RI
authors.lastname: Braun
authors.affiliation: Department of Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, IL 60208, USA.|Northwestern Institute for Complex Systems, Northwestern University, Evanston, IL 60208, USA.|Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, USA.
authors.forename: Daniel M
authors.identifier: 0000-0002-6015-8358
authors.initials: DM
authors.lastname: Abrams
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D052586:Mating Preference, Animal; D008962:Models, Theoretical; D012727:Sex Characteristics
keywords: competition; evolution; handicap principle; natural selection; ornament; sexual selection