title: Telomeres shorten and then lengthen before fledging in Magellanic penguins (Spheniscus magellanicus).
abstract: For all species, finite metabolic resources must be allocated toward three competing systems: maintenance, reproduction, and growth. Telomeres, the nucleoprotein tips of chromosomes, which shorten with age in most species, are correlated with increased survival. Chick growth is energetically costly and is associated with telomere shortening in most species. To assess the change in telomeres in penguin chicks, we quantified change in telomere length of wild known-age Magellanic penguin (Spheniscus magellanicus) chicks every 15 days during the species' growth period, from hatching to 60 days-of-age. Magellanic penguins continue to grow after fledging so we also sampled a set of 1-year-old juvenile penguins, and adults aged 5 years. Telomeres were significantly shorter on day 15 than on hatch day but returned to their initial length by 30 days old and remained at that length through 60 days of age. The length of telomeres of newly hatched chicks, chicks aged 30, 45 and 60 days, juveniles, and adults aged 5 years were similar. Chicks that fledged and those that died had similar telomere lengths. We show that while telomeres shorten during growth, Magellanic penguins elongate telomeres to their length at hatch, which may increase adult life span and reproductive opportunities.
authors.affiliation: Department of Biology, University of Washington, Seattle, WA 98195, USA.
authors.forename: Jack A
authors.initials: JA
authors.lastname: Cerchiara
authors.affiliation: Department of Pathology, University of Washington, Seattle, WA 98195, USA.
authors.forename: Rosa Ana
authors.initials: RA
authors.lastname: Risques
authors.affiliation: Department of Pathology, University of Washington, Seattle, WA 98195, USA.
authors.forename: Donna
authors.initials: D
authors.lastname: Prunkard
authors.affiliation: School of Environmental and Forest Sciences, University of Washington, Seattle, WA 98195, USA.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Smith
authors.affiliation: Department of Biology, University of Washington, Seattle, WA 98195, USA.
authors.forename: Olivia J
authors.initials: OJ
authors.lastname: Kane
authors.affiliation: Department of Biology, University of Washington, Seattle, WA 98195, USA.|Wildlife Conservation Society, Bronx, NY 10460, USA.|Global Penguin Society, University of Washington, Seattle, WA 98195, USA.
authors.forename: P Dee
authors.initials: PD
authors.lastname: Boersma
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D046429:Spheniscidae; D016615:Telomere / Q000502:physiology*; D059505:Telomere Homeostasis / Q000502:physiology*; D059506:Telomere Shortening / Q000502:physiology*
keywords: aging; growth; life history; telomeres