title: An experimental demonstration that early-life competitive disadvantage accelerates telomere loss.
abstract: Adverse experiences in early life can exert powerful delayed effects on adult survival and health. Telomere attrition is a potentially important mechanism in such effects. One source of early-life adversity is the stress caused by competitive disadvantage. Although previous avian experiments suggest that competitive disadvantage may accelerate telomere attrition, they do not clearly isolate the effects of competitive disadvantage from other sources of variation. Here, we present data from an experiment in European starlings (Sturnus vulgaris) that used cross-fostering to expose siblings to divergent early experience. Birds were assigned either to competitive advantage (being larger than their brood competitors) or competitive disadvantage (being smaller than their brood competitors) between days 3 and 12 post-hatching. Disadvantage did not affect weight gain, but it increased telomere attrition, leading to shorter telomere length in disadvantaged birds by day 12. There were no effects of disadvantage on oxidative damage as measured by plasma lipid peroxidation. We thus found strong evidence that early-life competitive disadvantage can accelerate telomere loss. This could lead to faster age-related deterioration and poorer health in later life.
authors.affiliation: Centre for Behaviour and Evolution and Institute of Neuroscience, Newcastle University, Newcastle, UK daniel.nettle@ncl.ac.uk.
authors.forename: Daniel
authors.identifier: http://orcid.org/0000-0001-9089-2599
authors.initials: D
authors.lastname: Nettle
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.
authors.forename: Pat
authors.initials: P
authors.lastname: Monaghan
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Gillespie
authors.affiliation: Centre for Behaviour and Evolution and Institute of Neuroscience, Newcastle University, Newcastle, UK School of Biological Sciences, Plymouth University, Plymouth, UK.
authors.forename: Ben
authors.initials: B
authors.lastname: Brilot
authors.affiliation: Centre for Behaviour and Evolution and Institute of Neuroscience, Newcastle University, Newcastle, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bedford
authors.affiliation: Centre for Behaviour and Evolution and Institute of Neuroscience, Newcastle University, Newcastle, UK.
authors.forename: Melissa
authors.initials: M
authors.lastname: Bateson
mesh_terms: D000375:Aging; D000818:Animals; D003163:Competitive Behavior; D004739:England; D005260:Female; D008297:Male; D018384:Oxidative Stress; D046749:Starlings / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D059506:Telomere Shortening
keywords: Sturnus vulgaris; early-life adversity; early-life stress; oxidative stress; starlings; telomeres