title: Antler size provides an honest signal of male phenotypic quality in roe deer.
abstract: Identifying factors shaping secondary sexual traits is essential in understanding how their variation may influence male fitness. Little information is available on the allocation of resources to antler growth in territorial ungulates with low sexual size dimorphism. We investigated phenotypic and environmental factors affecting both absolute and relative antler size of male roe deer in three contrasting populations in France and Sweden. In the three populations, we found marked age-specific variation in antler size, with an increase in both absolute and relative antler size between yearling and prime-age stages, followed by a decrease (senescence) for males older than 7 years. Antler size increased allometrically with body mass. This increase was particularly strong for senescent males, suggesting the evolution of two reproductive tactics: heavy old males invested particularly heavily in antler growth (potentially remaining competitive for territories), whereas light old males grew small antlers (potentially abandoning territory defense). Finally, environmental conditions had little effect on antler size: only population density negatively affected absolute antler size in one of the three populations. Antler size may therefore provide an honest signal of male phenotypic quality in roe deer. We discuss the implications of these results in terms of territory tenure and mating competition.
authors.affiliation: Laboratoire Comportement et Ecologie de la Faune Sauvage, Institut National de la Recherche Agronomique, BP 52627, F-31326 Castanet-Tolosan Cedex, France. cecile.vanpe@toulouse.inra.fr
authors.forename: Cécile
authors.initials: C
authors.lastname: Vanpé
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Gaillard
authors.forename: Petter
authors.initials: P
authors.lastname: Kjellander
authors.forename: Atle
authors.initials: A
authors.lastname: Mysterud
authors.forename: Pauline
authors.initials: P
authors.lastname: Magnien
authors.forename: Daniel
authors.initials: D
authors.lastname: Delorme
authors.forename: Guy
authors.initials: G
authors.lastname: Van Laere
authors.forename: François
authors.initials: F
authors.lastname: Klein
authors.forename: Olof
authors.initials: O
authors.lastname: Liberg
authors.forename: A J Mark
authors.initials: AJ
authors.lastname: Hewison
mesh_terms: D000367:Age Factors; D000818:Animals; D000999:Antlers / Q000254:growth & development*; D001837:Body Weights and Measures; D002980:Climate; D003670:Deer / Q000254:growth & development*; D017753:Ecosystem; D005602:France; D008297:Male; D008954:Models, Biological; D010641:Phenotype; D011156:Population Density; D012641:Selection, Genetic; D012726:Sexual Behavior, Animal / Q000502:physiology; D013548:Sweden; D013731:Territoriality