Abstrakt

Economic effects of ectoparasites on fitness and life history.

Bobbi Fitze*

According to life history theory, iteroparous organisms will trade off current reproduction for future reproduction, leading to the evolution of host defences against current parasite infestation that will enhance lifelong reproductive success. Thus, the variance in reproductive success caused by parasites is not solely due to parasite infestation, but also results from the parasite-mediated distribution of resources across current and upcoming reproductive events. Therefore, an experimental research of the effects of parasites during the host's lifetime is necessary to comprehend the significance of parasites for the evolution of host life history. There is currently little such research. The components of current and future reproductive success, such as survival, divorce, breeding dispersal, and numerous reproductive characteristics, were documented while manipulating the load of an ectoparasite, the hen flea, in the nests of its most common host, the great tit, over a period of 4 years. Finally, we evaluated lifetime reproductive success as a close indicator of Darwinian fitness for females solely because male paternity was unknown. According to the experiment, females reproducing in contaminated nests scattered over greater distances between breeding attempts. Ectoparasites had no appreciable impact on the post-infestation divorce rate, likelihood of future local reproduction, or residual reproductive performance. According to the study, hen fleas have a negligible impact on how current and future reproduction is prioritised.