A new study, published in the Proceedings of the National Academy of Sciences, and performed by researchers at the university of Oxford, has shown that larger groups of birds are better at solving problems. The researchers suggest this effect may be explained through the higher chance that a ‘bright’ or ‘experienced’ bird is included in a larger group rather than in a smaller one.
This effect, also known as the ‘pool of competence’ is suggested to occur in human beings, but this study is the first one that hints it might also play a role in other animals.
By examining the problem-solving capacities of groups of great tits (Parus major) and blue tits (Cyanistes caeruleus) at automated devices (see video here), it was found that efficiency in using these devices increased with group size, as did the individual seed-intake of each bird (see figure 1).
Figure 1: (A) The proportion of devices solved increases with group size. (B) As the groups grows, so does the individual seed-intake.
(Source: Morand-Ferron and Quinn, 2011)
In the words of the authors:
In contrast to traditional group living theory, individuals joining larger flocks benefited from a higher seed intake, suggesting that group living facilitated exploitation of a novel food source through improved problem-solving efficiency.
Surprisingly, there did not seem to be an optimal group size, instead it seemed that ‘the larger the group, the better’ was the overall tenet.
It also became obvious that there were consistent inter-individual differences in the probability of success (one of the prerequisites of the ‘pool of competence’ hypothesis), and that the good problem-solvers were more successful when in larger groups and near protective tree cover, indicating that there might be a role for reduced predation-risk in problem-solving efficiency.
The authors conclude:
Together our results suggest that both ecological and social factors, through reduced predation risk and increased pool of competence, mediate innovation in natural populations.
References
Morand-Ferron, J. and Quinn, J.L. (2011). Larger groups of passerines are more efficient problem solvers in the wild. Proceedings of the National Academy of Sciences. 108(38), pp. 15898 –15903. doi: 10.1073/pnas.1111560108.
University of Oxford, News.
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