Trusted ‘superguards’ are no mere meerkats
A highly sophisticated social system keeps these desert dwellers from danger
For three months a researcher from the University of Zurich kept a beady eye (and ear) on nine groups of meerkats in the Kalahari and discovered something extraordinary about their social lives: while some foraged, the ones that proved their worth as excellent sentries acquired good reputations and, as a result, were “promoted” to be “superguards”.
Normally, among species that forage for food, the most trusted warning that danger might be present comes from older individuals or those who are generally dominant.
But animal behaviour specialist Ramona Rauber, from the university’s department of evolutionary biology and environmental studies, found that meerkats operated in more of a meritocracy.“When foraging, meerkats mainly dig holes in the sand in search of insects and small vertebrates, which prevents them from scanning their surroundings for predators,” she said.
Examples of predators include jackals, birds of prey and snakes, all of which might be hovering around ready to attack while the meerkats have their heads buried in the ground.“To minimise predation risk for the whole group, meerkats evolved an elaborate sentinel system with distinct sentinel calls. Sentinel calls have been shown to contain information about the caller’s identity, as well as the sentinel’s perceived risk levels. Sentinel calming calls, in particular, act as ‘all-clear’ signals,” Rauber said.
This means the rest of the group become less vigilant to danger and more engrossed in foraging as they implicitly trust the sentry’s all-clear signal.
Through her observations, Rauber ranked the sentries as “rare”, “common” and “super” — the last of which did lookout duty 50% more frequently than the others.
She then recorded their all-clear signals and played them back to individuals who were foraging on their own so they wouldn’t be influenced by others in the group. She attached a small speaker to her leg and stood quietly a metre or two away from each test individual.“Playing back sentinel calming calls given by different individuals to foraging test subjects in the same group revealed significant differences in the subjects’ vigilance levels depending on the identity of the sentinel,” she said.
The most important item on your CV if you’re a meerkat that wants to be a superguard is “the frequency with which the caller contributed to sentinel behaviour during the previous months”.
Rauber’s data revealed that superguards who earned their stripes through sentinel practice were the most highly trusted.
Meerkats are known for their social intelligence, and this latest study, published in Nature, proves their social structures and behaviour are more sophisticated than many other species.