Stopher Katie V, Pemberton Josephine M, Clutton-Brock Tim H, Coulson Tim
Division of Biology, Faculty of Life Sciences, Imperial College at Silwood Park, Ascot, Berks SL5 7PY, UK.
Proc Biol Sci. 2008 Sep 22;275(1647):2137-45. doi: 10.1098/rspb.2008.0502.
Variation between individuals is an essential component of natural selection and evolutionary change, but it is only recently that the consequences of persistent differences between individuals on population dynamics have been considered. In particular, few authors have addressed whether interactions exist between individual quality and environmental variation. In part, this is due to the difficulties of collecting sufficient data, but also the challenge of defining individual quality. Using a long-established study population of red deer, Cervus elaphus, inhabiting the North Block of the Isle of Rum, and three quality measures, this paper investigates how differences in maternal quality affect variation in birth body mass and date, as population density varies, and how this differs depending on the sex of the offspring and the maternal quality measure used. Significant interactions between maternal quality, measured as a hind's total contribution to population growth, and population density are reported for birth mass, but only for male calves. Analyses using dominance or age at primiparity to define maternal quality showed no significant interactions with population density, highlighting the difficulties of defining a consistent measure of individual quality.
个体间的差异是自然选择和进化变化的重要组成部分，但直到最近，个体间持续存在的差异对种群动态的影响才被考虑。特别是，很少有作者探讨个体质量与环境变化之间是否存在相互作用。部分原因在于收集足够数据存在困难，同时定义个体质量也具有挑战性。本文利用一个长期研究的马鹿种群（栖息在拉姆岛北块的赤鹿，Cervus elaphus）以及三种质量衡量指标，研究了随着种群密度变化，母体质量差异如何影响出生体重和日期的变化，以及这如何因后代性别和所使用的母体质量衡量指标而异。对于出生体重，报告了以母鹿对种群增长的总贡献来衡量的母体质量与种群密度之间存在显著的相互作用，但仅针对雄性幼崽。使用优势地位或初产年龄来定义母体质量的分析表明，与种群密度不存在显著的相互作用，这凸显了定义一致的个体质量衡量指标的困难。
