n an era before smartphones or social media or even permanent shelter, a social network branched no further than the members within a hunter-gatherer group.
In some pockets of the planet, that way of life still exists today. While modern social networks, particularly those that flourish on Facebook and Twitter, thrive on attention, these ancient relationships instead traded on a slightly more important commodity: food.
Based on an analysis by researchers publishing their work in the journal Current Biology, social hierarchies in hunter-gatherer tribes are closely related to food sharing.
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For the study, anthropologists at the University College London observed for several months two groups of hunter-gatherers, the Palanan Agta in the Philippines and the Mbendjele BaYaka in the Republic of Congo.
The U.K. team found that both populations shared multi-layered social structures with relationships and hierarchies forged by food sharing and reciprocity. An individual first shares food with immediate family, then three or four closely related households, then the wider camp, which can vary in size, the authors wrote.
No word yet on what the equivalent of a "Like" button would be in hunter-gatherer societies.
"Despite their geographical separation and different foraging niches, communities of Agta and Mbendjele hunter-gatherers are structured in similar ways," the authors wrote.
"We suggest that this multilevel social organization allows individuals access to the range of social relationships required to mitigate against day-to-day variability in foraging success inherent in the human foraging economy," they said.
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Last week, the same University of College London team published another study in the journal Open Science in which they concluded that the most stable hunter-gatherer camps are those in which food sharing is more common. In less-successful camps, individuals don't divide, but instead take food and other resources from others, a situation described by the researchers as "demand sharing."
Outside of humans, cooperation among unrelated individuals within a group is rare. "No other apes share food to the extent that humans do," said Andrea Migliano, co-author of both studies.
"Sharing is a crucial adaptation to hunter-gatherers' lifestyles, central to their resilience and central to the evolution of mankind," she added.
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