Barbary macaques cozy up to their grooming partners on cold and snowy nights
When the wintry chill sets into the air, nothing quite beats the warmth of snuggling up to a loved one – or, in the case of Morocco’s wild Barbary macaques, many loved ones.
Researchers have found that monkeys with a larger number of social partners have a better shot at surviving the winter, as the groups are able to form huge huddles to keep warm.
The technique, called thermoregulation, leaves the monkeys less exposed to environmental stresses, allowing them to save more energy for growth and reproduction.
Researchers have found that monkeys with a larger number of social partners have a better shot at surviving the winter, as the groups are able to form huge huddles to keep warm
‘In several species, research has found that the most sociable individuals within a group tend to experience greater survival, longevity, reproductive output, and offspring survival,’ says Dr Bonaventura Majolo, a behavioural ecologist based in the School of Psychology at the University of Lincoln.
‘We know from previous studies of a number of different species that forming social bonds positively affects survival and reproduction, but exactly how this happens was not clear.'
According to the researchers, this study is the first to show how the social bonding associated with huddling ties into the animals’ fitness.
The team observed the grooming behaviour and hierarchy of two wild groups in Morocco, observing their habits during the day and their preparations for night.
‘Barbary macaques were an ideal species to examine because of the varying social relationships they have with their group companions, and the extreme weather conditions they experience, such a cold and snowy winters, and hot and dry summers,' Majolo says.
‘We found that monkeys which were more sociable would huddle together during winter nights with their social partners, and that this led to the formation of larger huddles when it rained or the temperature dropped.’
The study showed that monkeys who spent more time grooming together were more likely to huddle.
And, when there was precipitation or especially low temperatures, they gathered in much larger groups.
According to the researchers, this study is the first to show how the social bonding associated with huddling ties into the animals’ fitness. The team observed the grooming behaviour and hierarchy of two wild groups in Morocco
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‘Social thermoregulation through huddling, communal nesting or communal roosting, is a very widespread behaviour across a range of species and this could therefore be a very widespread mechanism linking sociality with an evolutionary advantage,’ said Liz Campbell, Programme Director at the Moroccan Primate Conservation Foundation.
‘In the ecological conditions of our study where Barbary macaques experience severe winter energy deficits, the benefits provided by social thermoregulation can explain why more social monkeys are more likely to survive winter.
‘In less extreme climates, more effective social thermoregulation could allow greater energetic investment in growth and reproduction, contributing to the greater longevity, reproductive output, and offspring survival experienced by more social individuals in other species.’