Goats have not (yet) earned a reputation for their problem-solving abilities.
But if you hide food in a strange cup and put a lid on it, a goat may find a way, a new study finds. And not just any goat. Animals that functioned like outsiders in their social group were best at tackling and solving a problem.
Innovation can be defined as the ability to solve new problems or find novel solutions to familiar problems. In humans, innovative behaviour has played a crucial role for the success of our species. However, innovation is thought to also provide fitness benefits in species, especially in complex dynamic environments where socio-ecological challenges often vary.
To date, however, it is still unclear which factors predict the distribution of innovation across species and individuals.
Based on existing literature, the study focused on the following socio-ecological traits, which might be linked to higher cognitive skills and/or greater ability to innovate: fission–fusion dynamics, dietary breadth, social group size and domestication. The study started with predictions on innovation to be more likely in species with
- higher fission–fusion dynamics (Prediction 1),
- with a wider dietary breadth (Prediction 2),
- living in larger groups (Prediction 3) and/or
- having been domesticated (Prediction 4).
In terms of inter-individual variation, literature suggestings are that innovative behaviour should be more common in individuals who have more limited access to resources, in those who react more positively to novelty and in those who are less integrated in their social group. Therefore predictions are that innovation should be more likely
- in more subordinate individuals (Prediction 5),
- in females (Prediction 6),
- in younger individuals (Prediction 7),
- in less neophobic ones (Prediction 8) and
- in individuals that are less integrated in the social group (Prediction 9).
A total o 111 subjects belonging to 13 ungulate species were studied, including 6 impalas (Aepyceros melampus petersi), 13 mhorr gazelles (Nanger dama mhorr), 13 dorcas gazelles (Gazella dorcas osiris), 7 scimitar oryx (Oryx dammah), 7 dromedaries (Camelus dromedarius), 7 red deer (Cervus elaphus), 15 Barbary sheep (Ammotragus lervia), 6 giraffes (Giraffa camelopardalis rothschildi), 4 guanacos (Lama guanicoe), 4 lamas (Lama glama), 4 Przewalski horses (Equus ferus przewalskii), 9 sheep (Ovis aries) and two groups of goats (Capra aegagrus hircus), one with 9 and one with 7 individuals.
The study showed interspecific and intra-specific variation in innovation, in this study sample.
In particular, we found differences in the probability that ungulates participated in the task and solved it. Domesticated species and species with higher fission–fusion dynamics were more likely to participate in the task, and so were individuals that were less neophobic to novel objects. Moreover, less neophobic individuals and socially less integrated ones were more likely to solve the task.
By contrast, we found no differences across individuals or species in the latency to solve the task or in the probability of using more than one strategy to retrieve food (see electronic supplementary material for a video clip with an individual of each species solving the task using different strategies).
Overall, the study showed that personality traits and social integration play an important role in ungulates, by reliably explaining variation in problem solving skills. These results are only partially in line with findings in other species, and despite important limitations in our study, they suggest that different evolutionary pressures may be at work in different taxa. Therefore, ungulates constitute a valid model for the comparative study of cognition, and the inclusion of still understudied taxa appears a powerful tool to test the limits of current evolutionary hypotheses.