title: Elevation impacts the balance between growth and oxidative stress in coal tits.
abstract: The short favorable period of time available for the growth in seasonal environments could constrain the resources allocation between growth and other life-history traits, and the short-term fitness benefits of increased growth rate may prevail over other functions. Accelerated growth rates have been associated with long-term deleterious consequences (e.g., decreased lifespan), and recently oxidative stress (the imbalance between pro-oxidants generation and antioxidant defenses) has been suggested as a mediator of these effects. Here, we examined the impact of elevation on growth rate and self-maintenance parameters (resting metabolism, oxidative damage, and antioxidant defenses) of coal tit chicks (Periparus ater). We predicted that the shorter favorable season at the higher-elevation site could lead to a reallocation of resources towards growth at the expense of self-maintenance processes. We found that chicks at high elevation grew significantly faster in terms of body mass and body size. Chicks from the high-elevation site presented higher resting metabolism, higher oxidative damage level, but similar antioxidant defenses, compared to low-elevation chicks. Interestingly, the chicks exhibiting the better antioxidant defenses at 7 days were also those with the highest resting metabolic rate, and the chicks that grew at the faster rate within the high-elevation site were those with the highest levels of oxidative damage on DNA. Our study supports the idea that increasing elevation leads to a higher growth rate in coal tit chicks, possibly in response to a shorter favorable season. In accordance with life-history theory, a bigger investment in growth was done at the expense of body maintenance, at least in terms of oxidative stress.
authors.affiliation: Institut Pluridisciplinaire Hubert Curien, University of Strasbourg, Strasbourg, France, antoine.stier@gmail.com.
authors.forename: Antoine
authors.initials: A
authors.lastname: Stier
authors.forename: Anne
authors.initials: A
authors.lastname: Delestrade
authors.forename: Sandrine
authors.initials: S
authors.lastname: Zahn
authors.forename: Mathilde
authors.initials: M
authors.lastname: Arrivé
authors.forename: François
authors.initials: F
authors.lastname: Criscuolo
authors.forename: Sylvie
authors.initials: S
authors.lastname: Massemin-Challet
mesh_terms: D000531:Altitude; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001481:Basal Metabolism; D049628:Body Size; D004249:DNA Damage; D018384:Oxidative Stress; D046109:Passeriformes / Q000254:growth & development* / Q000378:metabolism; D013696:Temperature
chemical_list: D000975:Antioxidants