Bold Monkeys Learn Faster than Shy Monkeys

A group of cognitive and behavioral biologists conducted personality assessments and a battery of learning tests with common marmoset monkeys and found that a link with personality and learning, intertwined with family group membership, exists in these monkeys.


In recent decades personalities have been uncovered in animals from spiders to apes. Similar personality traits are often shared between animals characterized as “friends” and sometimes even their whole social groups.

Personalities have been linked to many life-history traits, but also to cognitive capabilities (like academic or work performance in humans). In animals, it has been suggested that more explorative and/or bolder individuals learn to solve various learning tasks faster. However, once they form these associations, they may be less flexible in reversing the learned links. Thus, in the new research, scientists focused on exploring whether such a link is also present in common marmoset monkeys, cooperatively breeding monkey species that parallel humans in many socio-cognitive traits, and to which extent this is interlinked with their family group membership.

Study overview

“The researchers first individually assessed personality of these monkeys by measuring their reactions in various tasks, like their engagement with novel or strange objects, new types of food, or time needed to approach a toy snake. With help of these tasks, they found that some monkeys were very explorative and bold, whereas others rather tried to avoid the stimuli and keep a distance. The researchers then assessed the monkeys’ learning performance in several learning tasks. For instance, in the simpler learning tasks, the monkeys were trained to hold a ‘target’ training stick, to stand on a weighing scale while holding a ‘target’ stick, and to reach the furthest point in the test set-up. The monkeys’ learning skills were also tested in other tasks, that were more challenging, where they had to either form an association between objects of the same size, but of different colors and shape, or between objects that had the same features, but had different sizes.”

Results overview

“Similar to findings in other animal species, marmoset monkeys learned consistently well across different cognitive tasks. The tested females learned overall faster than males. The researchers’ results largely supported the speed-accuracy trade-off framework: personality (in particular, trait Boldness-Shyness) predicted learning speed in these monkeys. However, social factors were also important: family group membership of these monkeys, especially when interlinked with their bold-shy tendencies seemed to affect how quickly they learn across different tasks. In particular, bolder monkeys learned faster than shy ones, which was especially evident for members of some family groups. The effect that belonging to certain family groups influenced learning speed may be due to shared social environment, previous mutual experiences, but also genetics. In evolutionary sense, that both personality and social environment affect learning is indeed plausible as bolder individuals are usually those that act upon new situations, and/or new or challenging physical and social environments. Such complex environments could then select for higher socio-cognitive performance.” (source)

Journal Reference: Vedrana Šlipogor, Christina Graf, Jorg J. M. Massen, Thomas Bugnyar. Personality and social environment predict cognitive performance in common marmosets (Callithrix jacchus). Scientific Reports, 2022; 12 (1) DOI: 10.1038/s41598-022-10296-8