EFFECTS OF SOCIAL AND ENVIRONMENTAL CONDITIONS ON EGG INVESTMENT: A LONG-TERM ASSESSMENT IN A COOPERATIVELY BREEDING BIRD

STUDENT SEMINAR IN BIODIVERSITY AND EVOLUTION

Breeding females can maximise their own and their offspring fitness by adjusting offspring phenotype to postnatal environment. Such maternal effects are expected when mothers can predict breeding environment quality based on current conditions such as food abundance, temperature or presence of predators. In avian species, females may use these cues to differently invest in egg size and number. In cooperative breeding systems, mothers have been found to use the presence of helpers as a cue of enhanced conditions. Few studies have assessed within-individual allocation strategies as breeding environment varies, but long-term investigations suggest significant plasticity in females’ response to helpers’ presence. Here I will present the results of the first chapter of my PhD project. I analysed data collected over 9 years in order to understand female investment decisions in relation to their social and environmental breeding conditions in a cooperatively breeding species, the sociable weaver Philetairus socius.

Rita Fortuna is a 2nd year PhD student in the BIODIV PhD Programme. She became a Master in Biodiversity, Genetics and Evolution in 2016 and completed her graduation in Biology in 2014, both in University of Porto. Her main areas of research are animal behaviour and evolutionary ecology. Rita is currently developing her PhD project under the supervision of Rita Covas (CIBIO-InBIO) and Claire Doutrelant (CEFE-CNRS). Using sociable weavers as a study system, Rita’s PhD project combines long-term and experimental data to explore prenatal maternal effects and their fitness consequences for offspring, parents and helpers.