Are exotic species red queens?

We combined two general hypotheses from the fields of invasion biology and evolutionary biology, the enemy release hypothesis and the Red Queen hypothesis, into the new invasive queens hypothesis. This hypothesis predicts that if species with the principal ability to reproduce both sexually and asexually are introduced to an exotic range, they show a shift towards asexual reproduction in the exotic range. The reasoning behind this hypothesis is that (1) species tend to leave behind their natural enemies when being introduced to an exotic range (enemy release hypothesis) and (2) sexual reproduction is less advantageous in the absence of natural enemies due to its high costs (inverted Red Queen hypothesis). We tested the invasive queens hypothesis against data from 70 animal species, based on information from the literature and unpublished information provided by 105 experts from various continents. As predicted, the investigated species showed a significant shift towards asexual reproduction in their exotic as compared to their native range.

我们将入侵生物学与进化生物学领域的两项通用假说——天敌释放假说（Enemy Release Hypothesis）与红皇后假说（Red Queen Hypothesis）——整合为全新的入侵皇后假说（Invasive Queens Hypothesis）。该假说预测：若兼具有性生殖与无性生殖核心能力的物种被引入外来分布区，其在该外来分布区中会转向无性生殖策略。该假说的理论逻辑包含两点：其一，物种被引入外来分布区时，通常会脱离其原生天敌群落，即天敌释放假说；其二，在缺失天敌的情境下，有性生殖因其高昂的成本而优势尽失，即逆向红皇后假说。我们依托公开文献与来自各大洲105位专家提供的未公开资料，针对70种动物的相关数据开展了入侵皇后假说的实证检验。结果与假说预测一致：相较于原生分布区，所研究的物种在外来分布区中呈现出向无性生殖显著转变的趋势。