In a recent study, researchers from Swansea University examined how social hierarchies affect sleep patterns among chacma baboons in South Africa. The team used GPS and accelerometer collars to monitor the activity of a baboon troop both during the day and at night.
Marco Fele, a PhD student at Swansea University and lead author of the study, explained: “We expected dominant baboons to get better rest at night, perhaps because they could choose the most comfortable or sheltered spots. But we found the opposite – dominant baboons had less and more interrupted rest.”
The research revealed that baboons tend to synchronize their resting and waking periods at night. However, dominant individuals are often surrounded by more group members, leading to increased disturbances as they are more likely to wake each other up.
Professor Andrew King, co-author of the study, commented: “Just like in humans, sleep is essential for health and decision-making. If dominant individuals are resting less at night, it could affect their performance and wellbeing. Equally, it may be that baboons get enough rest overall, so the costs would be minimal. Future work now needs to test the consequences of these night-time disruptions.”
This study is the first to show that social hierarchies can impact sleep among wild primates. It suggests that leadership during the day might come with disadvantages during rest periods. The findings also demonstrate how social relationships and dominance influence behaviour even when animals are sleeping, made possible by advances in tracking technology.