Scheme: University Research Fellowship
Organisation: University of Exeter
Dates: Oct 2008-Jun 2012
Summary: Cooperative breeding occurs in an animal when individuals commonly provide care to the offspring of other individuals. It is most famously observed in insects like bees, wasps, ants and termites, but is also common in mammals like meerkats and humans. Understanding the evolution of such systems is perplexing because individual behaviour should be governed by genes and it is difficult to see how genes for cooperation can be passed from one generation to the next when individuals refrain from breeding. Testing these problems in social insects is difficult because most societies are highly social, making it difficult to test the underlying causes, whilst in humans, experiments are difficult to conduct for ethical reasons. I use cooperative birds as a model system to understanding how societies evolve and are stabilised, because they generally breed in simple pairs as well as groups and are easy to conduct observations on. It is hoped that insights from birds can be used to understand how societies develop and evolve more generally. One way in which societies might be stabilised is if all individuals have a common interest. I tested this idea in chestnut-crowned babblers, a 50g bird endemic to deserts of south-eastern Australia. This is one of the most cooperative birds in the world, breeding in groups of two to 15 individuals. Over the past years I have been studying a population of 80 groups, in which all birds are known. I have found that mothers manipulate the size of the eggs they lay when breeding in different-sized groups and that this influences the success of their offspring (their size and probability of leaving the nest). Next year, I will investigate whether this also affects the probability that offspring stay at home and help or disperse to breed, and in the former, whether it affects the amount that individuals invest in helping. If this is the case, this will help us to understand the role that mothers have in stabilizing cooperative groups.
Organisation: University of Sheffield
Dates: Oct 2003-Sep 2008
Summary: This project summary is not available for publication.