Centre for Ocean Life, DTU Aqua, Technical University of Denmark, Lyngby, Denmark.
Evolutionary Ecology of Marine Fishes, GEOMAR, Helmholtz Centre for Ocean Research, Kiel, Germany.
Glob Chang Biol. 2018 Mar;24(3):1164-1174. doi: 10.1111/gcb.13955. Epub 2017 Nov 14.
Species establishing outside their natural range, negatively impacting local ecosystems, are of increasing global concern. They often display life-history features characteristic for r-selected populations with fast growth and high reproduction rates to achieve positive population growth rates (r) in invaded habitats. Here, we demonstrate substantially earlier maturation at a 2 orders of magnitude lower body mass at first reproduction in invasive compared to native populations of the comb jelly Mnemiopsis leidyi. Empirical results are corroborated by a theoretical model for competing life-history traits that predicts maturation at the smallest possible size to optimize r, while individual lifetime reproductive success (R ), optimized in native populations, is near constant over a large range of intermediate maturation sizes. We suggest that high variability in reproductive tactics in native populations is an underappreciated determinant of invasiveness, acting as substrate upon which selection can act during the invasion process.
物种在其自然分布范围之外定殖，对当地生态系统产生负面影响，这引起了越来越多的全球关注。它们通常表现出 r 选择种群的特征，具有快速生长和高繁殖率，以实现在入侵栖息地的正种群增长率(r)。在这里，我们证明了在栉水母 Mnemiopsis leidyi 的入侵种群与本地种群相比，首次繁殖时的成熟度要早得多，而且其体型小两个数量级。实证结果得到了一个竞争生活史特征的理论模型的支持，该模型预测了以最小的可能体型成熟，以优化 r，而在本地种群中优化的个体终身繁殖成功率(R)，在较大的中间成熟体型范围内几乎保持不变。我们认为，本地种群中繁殖策略的高度可变性是一个被低估的入侵决定因素，它作为一个基质，在入侵过程中选择可以作用于其上。
