Phenological mismatch drives selection elevation, but not on slope, of breeding time plasticity in a wild songbird

TY - JOUR

T1 - Phenological mismatch drives selection elevation, but not on slope, of breeding time plasticity in a wild songbird

AU - Ramakers, J.J.C.

AU - Gienapp, P.

AU - Visser, M.E.

N1 - 6662, AnE; Data Archiving:archived at Dryad

PY - 2019

Y1 - 2019

N2 - Phenotypic plasticity is an important mechanism for populations to respond to fluctuating environments, yet may be insufficient to adapt to a directionally changing environment. To study whether plasticity can evolve under current climate change, we quantified selection and genetic variation in both the elevation (RNE) and slope (RNS) of the breeding time reaction norm in a long‐term (1973–2016) study population of great tits (Parus major). The optimal RNE (the caterpillar biomass peak date regressed against the temperature used as cue by great tits) changed over time, whereas the optimal RNS did not. Concordantly, we found strong directional selection on RNE, but not RNS, of egg‐laying date in the second third of the study period; this selection subsequently waned, potentially due to increased between‐year variability in optimal laying dates. We found individual and additive genetic variation in RNE but, contrary to previous studies on our population, not in RNS. The predicted and observed evolutionary change in RNE were, however, marginal, due to low heritability and the sex limitation of laying date. We conclude that adaptation to climate change can only occur via micro‐evolution of RNE, but this will necessarily be slow and potentially hampered by increased variability in phenotypic optima.

AB - Phenotypic plasticity is an important mechanism for populations to respond to fluctuating environments, yet may be insufficient to adapt to a directionally changing environment. To study whether plasticity can evolve under current climate change, we quantified selection and genetic variation in both the elevation (RNE) and slope (RNS) of the breeding time reaction norm in a long‐term (1973–2016) study population of great tits (Parus major). The optimal RNE (the caterpillar biomass peak date regressed against the temperature used as cue by great tits) changed over time, whereas the optimal RNS did not. Concordantly, we found strong directional selection on RNE, but not RNS, of egg‐laying date in the second third of the study period; this selection subsequently waned, potentially due to increased between‐year variability in optimal laying dates. We found individual and additive genetic variation in RNE but, contrary to previous studies on our population, not in RNS. The predicted and observed evolutionary change in RNE were, however, marginal, due to low heritability and the sex limitation of laying date. We conclude that adaptation to climate change can only occur via micro‐evolution of RNE, but this will necessarily be slow and potentially hampered by increased variability in phenotypic optima.

KW - NIOO

KW - genetic variation

KW - life-history evolution

KW - natural selection

KW - phenotypic plasticity

KW - quantitative genetics

KW - Fitness

UR - https://doi.org/10.5061/dryad.35k1n3m

U2 - 10.1111/evo.13660

DO - 10.1111/evo.13660

M3 - Article

SN - 1558-5646

VL - 73

SP - 175

EP - 187

JO - Evolution

JF - Evolution

IS - 2

ER -