Genes take a backseat: Early-life environments shape social behaviour in adult great tits
A new study led by the University of Oxford has revealed that the social lives of great tits are far more influenced by their environment than their genetic makeup, and that their early-life environment shapes adult behaviour. By combining extensive observational datasets from Wytham Woods in Oxford, with cutting-edge multi-matrix quantitative genetic models, the team has developed a powerful framework for disentangling genetic and environmental influences on behaviour.
Wytham Woods, owned and maintained by the University of Oxford, is an iconic location subject to continuous ecological research programmes dating back to the 1940s. The long-term monitoring of hundreds of breeding great tits each year means that these woodlands provided a unique opportunity to measure the heritability of social traits.
Researchers constructed social networks of the birds using observational data of great tits foraging together during the winter. However, to investigate whether these behaviours were genetically inherited, the team had to apply quantitative genetic methods, including advanced statistical methods used to partition the genetic and environmental components of complex traits. Professor Ben Sheldon said of the interdisciplinary method:
“The causal factors in wild systems are notoriously challenging to disentangle. We hope this study acts as a valuable framework for quantitative genetic modelling in wild systems and guides future research in this area.”
The surprising result? Social behaviours in great tits have virtually no genetic basis. Instead, the study highlights the overwhelming influence of environmental factors. Fine-scale aspects of the birds’ natal environment – such as where they were raised when young – and the spatial location of their winter foraging grounds were found to play a much larger role in shaping social behaviour. These findings suggest that developmental conditions in early life can have long-lasting impacts on how individuals behave socially as adults. Dr Irem Sepil says:
“This discovery has significant implications for our understanding of how social behaviour evolves. It suggests that the environment – rather than genes – plays the dominant role in shaping social behavioural traits. This challenges long-held assumptions about the heritability of sociality in animal populations.”
Devi Satarkar, lead author of the study concludes
“Our findings emphasise the importance of incorporating fine-scale environmental data into studies of animal behaviour. We’re excited to explore this further, particularly the influence that climatic conditions and habit features in the developmental environment can have in shaping later adult behaviour.”
The paper ‘Genetic, natal and spatial drivers of social phenotypes in wild great tits’ has been published in Journal of Animal Ecology. It is available online at: doi.org/10.1111/1365-2656.14234
Great tit in Wytham Woods
Photo by David López Idiáquez
