Scientists at the University of Miami tested a total of 48 captive carnivores using puzzle boxes filled with beef to test the "social intelligence hypothesis." To get to the tasty morsel, these lions, leopards, tigers and hyenas had to channel their inner Einstein to activate a spring-loaded door latch by pulling on a rope attached to the box.
The "social intelligence hypothesis" proposes that social complexity results in cognitive complexity. Living a communal life requires problem solving skills that may not be needed for a solitary lifestyle. Keeping track of the group (who is friend or foe), working cohesively as a group, and learning from group members privides an advantage to those living in said group. And, being a better group member typically results in greater fitness, therefore, better social behavior results in improved problem solving leading to greater cognitive abilities within the species. So, does the social intelligence hypothesis have any merrit?
It seems to in big cats! Out of twelve lions tested at Florida's Lion Country Safari (some pictured left), eleven figured out how to get themselves a treat. Of those eleven, seven figured it out on their own and four learned how to do it from watching the other seven. Then, ten of the eleven were able to recall how to get the treat 5-7 months later.
- Hyena - 8/9 successful (88%); these guys are social, living in "clans" up to as many as 80 individuals!
- Lion - 16/21 successful (76%); the only social big cat, living in "prides" which are typically around 10-15 individuals
- Leopard - 6/11 successful (54%); solitary and territorial, only social learning is between mother and cub
- Tiger - 2/7 successful (29%); same as the leopard, except they like to swim
So, the more social the carnivore, the better they were at solving the puzzle. Other studies have found that across unrelated species, brain size has more to do with the ability to problem solve than social structure, but this study seems to suggest that in species that are more closely related (the Pathera genus is estimated to have a divergence time of only 3-4 million year ago), social stucture may be a factor in how well you're able to problem solve.