Animals With Larger Brains Are Better Problem-Solvers
Over the years, it has been found that species, such as humans and dolphins, which have larger brains related to their body sizes, are brainier than others with small brains, such as blue whales and hippos.
A study by researchers at the University of Wyoming supports the theory that bigger brains are more intelligent.
Information was collected from nine different zoos and 140 animals from 39 different mammalian carnivore species. They included polar bears, tigers and wolves, and scientists gave them all some tasks to solve problems in 30 minutes. Every animal was asked to take food from a closed metal box whose bolt latch could be slid open. The scientists kept a bit of food that was their favourite in the boxes.
Animals with brains that were larger in proportion to their bodies improved their tasks compared to species with smaller brains.
"This study offers a rare look at problem-solving in carnivores, and the results provide important support for the claim that brain size reflects an animal's problem-solving abilities and enhances our understanding of why larger brains evolved in some species," Sarah Benson-Amram, lead author of the study, said in a press release.
"Overall, 35 percent of animals (49 individuals from 23 species) were successful in solving the problem," added Ben Dantzer, co-author of the study. "The bears were the most successful, solving the problem almost 70 percent of the time. Meerkats and mongooses were the least successful, with no individuals from their species solving the problem."
The bigger animals were found to be not as successful than animals with smaller bodies. The physical dexterity was not linked with success on the job.
Earlier, species living in bigger groups have been thought to solve problems better, according to "the social brain hypothesis" but studies do not seem to prove the theory.
"If the social brain hypothesis is correct, then we would expect that species that live in larger social groups would be more intelligent," said Kay Holekamp, co-author of the study. "However, we did not find any support for the social brain hypothesis in this study. There was no indication that social group size influenced problem-solving abilities."
The findings were published in Dec. 16,2015 issue of the Proceedings of the National Academy of Sciences.