Live fast, die old: oxidative stress as a potential mediator of an unexpected life-history evolution

Intraspecific latitudinal patterns in life history are well documented, yet underlying mechanisms of such patterns are poorly understood. To advance our insights in the evolution of latitudinal differences in two key traits, growth rate and lifespan, we evaluated the potential costs of rapid growth in terms of reduced adult lifespan, and the mediatory role of oxidative stress. We studied latitudinal differentiation in routine and experimentally increased (compensatory) larval growth rates, and in adult lifespan under common garden conditions in low- and high-latitude populations of the damselfly Ischnura elegans. The low-latitude populations showed not only higher routine growth rates but also a stronger compensatory growth response after a transient food shortage compared to the high-latitude populations. In contrast with a trade-off scenario, adults of the faster growing low-latitude populations lived longer, had higher levels of antioxidant enzymes, and tended to experience lower oxi...