The drivers of individual growth rate variation in natural populations

Individual growth rate is a key life-history trait with potentially important fitness consequences. However, little research has been conducted in endotherms to understand its ecological and individual-level drivers. This trait is expected to be under strong selection, as it allows for individuals to reach the reproductive phase sooner. It is also strongly linked with body size, one of the few traits that help us structure the diversity of life histories strategies and predict with an acceptable level of confidence where a species stands in the slow- to fast-pace continuum of life. Several individual- and ecological-level factors are expected to drive variation on individual growth rate, but little research has been devoted to exploring this question in natural populations. What is the role of weather? Does predation risk impact growth? What about population density? Can we detect the expected negative effect of inbreeding in the wild? Addressing these questions requires long-term ecological studies that allow collecting high resolution physiological, behavioral and life trajectory information from free-ranging individuals in wild populations, coupled with spatially explicit habitat data and environmental monitoring. This allows for the daily biotic and abiotic environment that each individual experiences throughout its life to be disentangled and for its consequences to be linked to individual-level variation in growth.