Scientists, including researchers from The University of Western Australia, have uncovered evidence that a species' long-term adaption to living in extremely cold climates has led to the evolution of social behaviours such as extended care by mothers and the ability to live in large complex multilevel societies.
The team from UWA, China's Northwest University and the UK's University of Bristol looked at the social evolution of Asian colobine monkeys, which live in habitat ranging from tropical rainforests to snow covered mountains.
Adaptations to a cold climate promoted social evolution in Asian colobine primates, published in Science, found monkeys living in extremely cold locations had evolved to have more efficient hormonal pathways that may lengthen maternal care, leading to an overall increase in infant survival.
These adaptive changes also appeared to strengthen relationships between individuals, increase tolerance between males and enable the evolution to complex multilevel societies.
Co-author Dr Cyril Grueter, from UWA's School of Human Sciences, said the study tried to connect broad-scale patterns in social evolution with genetics.
"We identified some genetic changes that may have facilitated adaptive transitions in social organisation when the environment changed," Dr Grueter said.
He said the finding that complex multilevel societies had roots stretching back to climatic events in the distant evolutionary past had implications for a reconstruction of the human social system.
"With climate change becoming a hugely important environmental pressure on animals, it is hoped that this study will raise awareness of the need to investigate what course social evolution will take," Dr Grueter said.
Co-author Dr Kit Opie, from the University of Bristol, said the research offered new insights into the mechanisms that underpinned behavioural evolution in primates and could be used to address social evolutionary changes across a wide range of species including humans.
