Life histories and invasions: accelerated laying rate and incubation time in an invasive lizard, Anolis sagrei

Faster life histories are correlated with greater invasion success across taxa. However, comparisons of life-history traits across native and invasive ranges are rare, and thus it is unknown whether invasions lead directly to evolutionary shifts in life histories. Here we compare life history traits of three invasive populations of brown anoles (Anolis sagrei) to a representative native population. In a common garden, we measured a number of reproductive traits including egg-laying rate and incubation period. We hypothesized that invasive populations would exhibit faster reproduction because fast life histories are favoured both by the invasion itself and by shorter breeding seasons in the invasive range. Compared to native females, invasive females had shorter interlaying intervals and produced eggs that hatched more quickly. Invasive and native populations did not differ consistently in egg size, hatching success, or hatchling size. Our results indicate that life history traits have r...

跨各类群而言，更快的生活史策略与更高的入侵成功率显著相关。然而，针对本土与入侵分布区的生活史性状开展的比较研究仍较为匮乏，因此学界尚不明确入侵事件是否会直接引发生活史层面的演化转变。本研究以三个入侵种群的棕安乐蜥（Anolis sagrei）为对象，将其生活史性状与一个具有代表性的本土种群进行对比分析。我们通过同质园（common garden）实验，测定了多项繁殖性状，包括产卵速率与孵化周期。我们提出假说：入侵种群会展现出更快的繁殖策略，这是因为入侵过程本身以及入侵分布区较短的繁殖季，均会对快速生活史产生选择优势。与本土雌性个体相比，入侵种群的雌性安乐蜥产卵间隔更短，且其所产的卵孵化速度更快。入侵种群与本土种群在卵大小、孵化成功率以及幼体体型方面，并未表现出一致的差异。本研究结果表明，生活史性状已r...