Family is no laughing matter for spotted hyenas, say scientists. Researchers from Michigan State University in the US have found that the animals will step in to support their relatives during fights.
The team led by zoologists Jennifer Smith and Kay Holekamp found that groups of hyenas that work together to overcome their enemies seem to have an "evolutionary advantage".
"Females that work in teams are [more likely to survive] and pass on their genes," says Ms Smith. “They assist their kin in gaining a competitive advantage over other group members."
Ms Smith (pictured) and her colleagues anaesthetised hyenas using CO2 powered rifles to obtain blood samples.
"We then extracted DNA to assign genetic relationships among the hyenas. Interestingly, hyenas co-operated to help both their maternal and paternal relatives during fights," says Ms Smith.
The animals follow a surprisingly complex set of rules when making decisions about co-operation. For example, they are less likely to join a fight if there are threatening onlookers.
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