title: Elephants born in the high stress season have faster reproductive ageing.
abstract: Senescent declines in reproduction and survival are found across the tree of life, but little is known of the factors causing individual variation in reproductive ageing rates. One contributor may be variation in early developmental conditions, but only a few studies quantify the effects of early environment on reproductive ageing and none concern comparably long-lived species to humans. We determine the effects of 'stressful' birth conditions on lifetime reproduction in a large semi-captive population of Asian elephants (Elephas maximus). We categorise birth month into stressful vs. not-stressful periods based on longitudinal measures of glucocorticoid metabolites in reproductive-aged females, which peak during heavy workload and the start of the monsoon in June-August. Females born in these months exhibit faster reproductive senescence in adulthood and have significantly reduced lifetime reproductive success than their counterparts born at other times of year. Improving developmental conditions could therefore delay reproductive ageing in species as long-lived as humans.
authors.affiliation: Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom.
authors.forename: Hannah S
authors.initials: HS
authors.lastname: Mumby
authors.affiliation: Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom.
authors.forename: Khyne U
authors.initials: KU
authors.lastname: Mar
authors.affiliation: Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom.|Institute of Evolutionary Biology, University of Edinburgh, Edinburgh EH9 3JT, United Kingdom.
authors.forename: Adam D
authors.initials: AD
authors.lastname: Hayward
authors.affiliation: Ministry of Environmental Conservation and Forestry, Myanma Timber Enterprise, Yangon, Myanmar.
authors.forename: Win
authors.initials: W
authors.lastname: Htut
authors.affiliation: Department of Veterinary Medicine, Yezin University, Myanmar.
authors.forename: Ye
authors.initials: Y
authors.lastname: Htut-Aung
authors.affiliation: Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom.
authors.forename: Virpi
authors.initials: V
authors.lastname: Lummaa
mesh_terms: D000375:Aging; D000818:Animals; D004606:Elephants / Q000502:physiology*; D005260:Female; D005938:Glucocorticoids / Q000378:metabolism; D012098:Reproduction / Q000502:physiology*; D012621:Seasons; D013312:Stress, Physiological
chemical_list: D005938:Glucocorticoids