Mosaic metabolic ageing: Basal and standard metabolic rate age in opposite directions and independent of environmental quality, sex or lifespan in a passerine

Abstract

9 1. Crucial to our understanding of the ageing process is identifying how traits change with 10 age, which variables alter their ageing process and whether these traits associate with 11 lifespan. 12 2. We here investigated metabolic ageing in zebra finches. We longitudinally monitored 407 13 individuals during six years and collected 3213 measurements of two independent mass-14 adjusted metabolic traits: basal metabolic rate (BMRm) at thermoneutral temperatures 15 and standard metabolic rate (SMRm), which is the same as BMRm but at ambient 16 temperatures below thermoneutrality. 17 3. BMRm decreased linearly with age, consistent with earlier reports. In contrast, SMRm 18 increased linearly with age. To the best of our knowledge, this is the first quantification of 19SMRm aging, and thereby of the contrast between SMRm and BMRm aging. 20 4. Neither metabolic trait or individual aging pattern was associated with individual lifespan. 21 Moreover, experimental manipulations of environmental quality that decreased BMRm 22

Mosaic metabolic ageing: Basal and standard metabolic rates age in opposite directions and independent of environmental quality, sex and life span in a passerine

“…Data available from the Dryad Digital Repository https://doi.org/10.5061/dryad.pzgmsbck8 (Briga & Verhulst, 2021).…”

Sex-specific body mass ageing trajectories in adult Asian elephants

“…Hence, the ageing trajectories do not synchronise between traits in females. Empirically, this heterogeneity of ageing patterns is more the rule than the exception as found in other species (Briga & Verhulst, 2021; Hayward et al, 2015; Walker & Herndon, 2010). In our population, this mismatch can be explained by the fact that body mass is a poor predictor of reproductive success, number of offspring produced or raised up to independence (5 years old), and that no relationship between height and survival has been found in females (Crawley et al, 2017).…”

Sex‐specific body mass ageing trajectories in adult Asian elephants

“…Hence, the ageing trajectories do not synchronize between traits in females. Empirically, this heterogeneity of ageing patterns is more the rule than the exception as found in other species (Briga & Verhulst, 2021; Hayward et al, 2015; Walker & Herndon, 2010). In our population, this mismatch can be explained by the fact that body mass is a poor predictor of reproductive success, number of offspring produced or raised up to independence (5 years old), and that no relationship between height and survival has been found in females (Crawley et al, 2017).…”