title: Endocranial volume is heritable and is associated with longevity and fitness in a wild mammal.
abstract: Research on relative brain size in mammals suggests that increases in brain size may generate benefits to survival and costs to fecundity: comparative studies of mammals have shown that interspecific differences in relative brain size are positively correlated with longevity and negatively with fecundity. However, as yet, no studies of mammals have investigated whether similar relationships exist within species, nor whether individual differences in brain size within a wild population are heritable. Here we show that, in a wild population of red deer (Cervus elaphus), relative endocranial volume was heritable (h2= 63%; 95% credible intervals (CI) = 50-76%). In females, it was positively correlated with longevity and lifetime reproductive success, though there was no evidence that it was associated with fecundity. In males, endocranial volume was not related to longevity, lifetime breeding success or fecundity.
authors.affiliation: Department of Zoology , University of Cambridge , Cambridge , UK.
authors.forename: C J
authors.identifier: 0000-0002-5944-906X
authors.initials: CJ
authors.lastname: Logan
authors.affiliation: Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK; Division of Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Canberra, Australia.
authors.forename: L E B
authors.initials: LE
authors.lastname: Kruuk
authors.affiliation: Department of Zoology , University of Cambridge , Cambridge , UK.
authors.forename: R
authors.initials: R
authors.lastname: Stanley
authors.affiliation: Department of Zoology , University of Cambridge , Cambridge , UK.
authors.forename: A M
authors.initials: AM
authors.lastname: Thompson
authors.affiliation: Department of Zoology , University of Cambridge , Cambridge , UK.
authors.forename: T H
authors.initials: TH
authors.lastname: Clutton-Brock
keywords: endocranial volume; fecundity; fitness; life history; longevity; quantitative genetics