The Evolutionary Demography of Ecological Change: Linking Trait Variation and Population Growth
Fanie Pelletier,1
Tim Clutton-Brock,2
Josephine Pemberton,3
Shripad Tuljapurkar,4
Tim Coulson1*
Population dynamics and evolutionary change are linked by the fundamental biological processes of birth and death. This means that population growth may correlate with the strength of selection, whereas evolutionary change can leave an ecological signature. We decompose population growth in an age-structured population into contributions from variation in a quantitative trait. We report that the distribution of body sizes within a population of Soay sheep can markedly influence population dynamics, accounting for up to one-fifth of observed population growth. Our results suggest that there is substantial opportunity for evolutionary dynamics to leave an ecological signature and visa versa.
1 Division of Biology and the Natural Environment Research Council (NERC) Centre for Population Biology, Imperial College London, Silwood Park, Ascot, Berkshire, SL5 7PY, UK.
2 Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK.
3 Institute of Evolutionary Biology, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JT, UK.
4 Department of Biological Sciences, Stanford University, Stanford, CA 94305–5020, USA.
* To whom correspondence should be addressed. E-mail: t.coulson{at}imperial.ac.uk
