Prehatching Temperatures Drive Interannual Cohort Differences In Great Tit Metabolism [post]

Juli Broggi, Esa Hohtola, Kari Koivula, Seppo Rytkönen, Jan-Åke Nilsson
2021 unpublished
Basal metabolic rate (BMR) constitutes the lowest metabolic rate in a resting animal and is therefore considered to reflect the energetic cost of maintenance in endotherms. BMR is a reversible plastic trait that changes with environmental and ecological circumstances, albeit being heritable and susceptible to selection. Inter-individual variation within populations of small birds is substantial, and while many of the drivers of such variation have been identified, many remain unexplained. Some
more » ... f the variation can be ascribed to cohort effects, indicating non-reversible developmental plasticity that will shape the adult metabolic phenotype. We studied winter BMR variation of juveniles over a fifteen-year period in a wild population of great tits Parus major at the northern border of their distribution. Here we show for the first time that winter BMR in cohorts of great tits changes among winters as a response to minimum ambient temperatures experienced early in life, during the prehatching period. This developmental plasticity might be adaptive if temperatures experienced by growing embryos would metabolically prime them to an environment that they will likely encounter in future life. However, in line with a more unpredictable future climate, the risk of phenotype-environment mismatch is likely to lead to certain cohorts being poorly adapted to prevailing winter conditions, resulting in wider annual fluctuations in population size.
doi:10.21203/rs.3.rs-875558/v1 fatcat:nhhuw4ofwng2voitvy7mkn2tgm