“Naïve juveniles are more likely to become breeders after witnessing predator mobbing”

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Michael Griesser and Toshitaka Suzuki

Predator mobbing teaches naïve juveniles to recognize their predators, boosting their survival and lifetime fitness

Learn for life: young birds learn to recognize predators from experienced individuals, boosting their survival and the likelihood to become breeders

The remains of a juvenile Siberian jay (Perisoreus infaustus) killed by a goshawk (Accipiter gentilis).
(Credit: Michael Griesser)

The success of our own species largely relies on our ability to acquire knowledge and skills from others (i.e., social learning). Infants learn during their development both language and skills from their parents, peers and teachers. Thus, social learning has been suggested to be a critical component of human evolution, accelerating the acquisition of knowledge and forming the base of human culture, innovation and language. An open question is how this ability could be favoured by Darwinian evolution. Studies in birds and mammals showed that social learning occurs in many species, where naïve individuals learn from other individuals how to respond to predators, care for offspring or choose mates. However, the long-term benefits of social learning, and thus its evolutionary basis, remained so far largely unclear.

A group of Siberian jays interacting on food, the bird in the background is an immigrant group member that is not tolerated on food and does not receive nepotistic antipredator protection from the breeders. However, given a social learning opportunity when breeders mob a goshawk, both retained offspring and immigrants learn to recognize the risk posed by a goshawk and have an increased subsequent survival.
(Credit: Michael Griesser)

A study by Michael Griesser (Zurich University) and Toshitaka Suzuki (Kyoto University) appearing in The American Naturalist reveals the long-term benefits of social learning in a wild bird species, the Siberian jay (Perisoreus infaustus). These birds live in family groups where juveniles remain with their parents up to 3 years. Goshawks (Accipiter gentilis) account for 70% of all deaths of jays, although natural encounters with goshawks are very rare. Thus, how do juveniles learn to recognize predators and respond appropriately? To answer this question, Griesser and Suzuki exposed Siberian jay groups to predator models, finding that naïve juveniles had a substantially higher first-winter survival after observing experienced group members approaching and mobbing a goshawk model (i.e., giving warning calls, swooping over the predator model). Moreover, this social learning increases the likelihood of juveniles to acquire a breeding position later in life.

These findings are of fundamental importance, empirically confirming the assumption that social learning is an adaptive strategy to acquire vital life skills. A single social learning opportunity had life-long consequences, which emphasizes the evolutionary importance of social learning for all species that acquire knowledge from others, including our own species. If social learning is combined with continuous innovation and cognitive abilities, this process can excel and provide the base for culture as the case in our own species. Thus, studies in animals can provide important evolutionary insights into the factors that make humans unique. Read the Article