Life history trade‐offs are more pronounced for a noninvasive, native butterfly compared to its invasive, exotic congener

Abstract

AbstractLife history trade‐offs are ubiquitous in nature. Life history theory posits that these trade‐offs arise from individuals having limited resources to allocate toward all vital functions, such as survival, growth and reproduction. These trade‐offs position most species along a slow‐fast life history continuum, where individuals with slow life histories often have higher survival at the cost of delayed reproduction and individuals with fast life histories often live faster and die younger. However, these trade‐offs are sometimes less obvious for invasive species. Here, we constructed age‐based population models to compare life history strategies and trade‐offs between the noninvasive, native mustard white and invasive, exotic cabbage white (Pieris spp.) butterflies. We found that the cabbage white has faster larval growth and higher fecundity at younger ages, suggesting it has a fast life history compared to the mustard white. However, cabbage white also has higher adult survival at younger ages, suggesting that it experiences weaker trade‐offs among vital rates than its native counterpart. Our study illustrates the importance of demographic studies in evaluating life history strategies among congener species with different population histories, and emphasizes the many advantages experienced by invasive species in their novel environments.