A new study published in Proceedings of the National Academy of Sciences supports the controversial hypothesis that big brains are better for problem solving. 

In this video, zoo animals were presented the task of getting  food out of a puzzle box. Each animal was got 30 minutes to figure out how to slide a bolt to open the box and get its favorite food. 

The lead author, Sarah Benson-Amram, an assistant professor in the Department of Zoology and Physiology at the University of Wyoming, explained in a press release that “[t]his 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 enhance our understanding of why larger brains evolved in some species.” 

Ben Dantzer, an assistant professor at the University of Michigan is another author. He explains in the press release that, "Overall, 35 percent of animals (49 individuals from 23 species) were successful in solving the problem. 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 species in this video,  listed in order of appearance, are:  Red Panda (Ailurus fulgens), Binturong (Arctictis binturong), Grizzly Bear (Ursus arctos), White-nosed Coati (Nasua narica), Bobcat (Lynx rufus), Arctic Fox (Alopex lagopus), Polar Bear (Ursus maritimus), Black Bear (Ursus americanus), Snow Leopard (Panthera uncia), Pallas cat (Otocolobus manul), Striped Hyena (Hyaena hyaena), Spotted Hyena (Crocuta crocuta), American Badger (Taxidea taxus), Leopard (Panthera pardus), Amur Tiger (Panthera tigris), River Otter (Lontra canadensis), Maned Wolf (Chrysocyon brachyurus), Wild Dog (Lycaon pictus), and Wolverine (Gulo gulo).