Abstracts (first author)
Age related changes in fitness traits in a wild field cricket population
Evidence for senescence in nature has been found in a growing number of vertebrate species, particularly birds and mammals, and more recently in a few invertebrates. Insects have proved very suitable for the study of senescence in laboratory studies but their mobility and small size make them very difficult to follow in their natural environment. We have extended the study of insect ageing into the wild, by using up to 90 video cameras to continuously monitor a natural field cricket population. We tagged individuals immediately after they became adult and followed them until their death was either inferred or directly observed. We recorded mating and fighting success, singing activity and movement over the entire adult life of individual crickets for five consecutive generations. We examine changes in behaviour over the adult lifespan and relationships with reproductive success. This allows us to determine whether crickets senesce in our population in terms of both survival probability and changes in behavioural measures such as activity, and to ask questions about interactions between ageing and sexual selection. Our model system provides an excellent opportunity for the study of the selective pressures acting on life history and ageing in wild insects.