A tradeoff between robustness to environmental fluctuations and speed of evolution

The ability of a species to cope with both long-term and short-term environmental fluctuations might vary with the species' life history. While some life-history characteristics promote large and stable population sizes despite interannual environmental fluctuations, other life-history strategies might allow to evolve quickly in response to long-term gradual changes. In a theoretical study, we show that there is a tradeoff between both properties. Life-history characteristics that promote fast rates of evolution come at the expense of a poor response to short-term environmental fluctuations, and vice versa. We demonstrated the presence of this tradeoff by the use of a mathematical analysis and individual-based simulations.

物种应对长期与短期环境波动的能力，或因自身生活史（life history）特征的差异而有所不同。尽管部分生活史特征可在年际环境波动下促进种群维持较大且稳定的规模，但另有部分生活史策略则可助力物种快速演化，以适应长期渐进性的环境变化。本项理论研究证实，这两类特性之间存在进化权衡关系。可提升演化速率的生活史特征，往往会以对短期环境波动的响应能力不足为代价，反之亦然。我们通过数学分析与基于个体的模拟（individual-based simulations），验证了该权衡关系的存在。