A new study has shown that animals with larger brains have more self-control when compared with animals with a smaller brain size. Scientists at Duke University, UC Berkeley, Stanford, Yale, and more than two dozen research institutions worked on the study.

Not only do animals with the largest brain volume show a higher rate of self-control, but the same can also be said for animals with varied diets. This proves that the right diet has a lot to do with brain power and how effectively animals and humans perform daily activities.

The study looked at 36 species of mammals and birds and shows that brain volume and not body size helps determine self-control in animals. It's the reason why a parrot can be considered smarter than an elephant. It might be difficult to believe, but the researchers have the evidence to back up their claim that it's brain volume, not volume relative to body size.

Researchers have found out that chimps have more self-control than gerbils or fox squirrels. They defined self-control as the ability to restrain one's self from behaving in a way that is counterproductive.

To conclude which animals could show self-control, researchers performed several tests. One test required the animals to figure out where to find food, after being shown where it was placed. Researchers used three cups, labeled cup A, B, and C. The animals were shown in a clear manner which cup had food placed in it. Researchers mainly placed food in cup A. The cups were then turned upside down to make sure the baited cup was not visible to the animals.

Animals only moved to the next level of testing if they successfully choose the cup with the food inside three times in a row. After this, the researchers would then change the food cup from A to C.

"The question was, would they approach cup A, where they had originally learned the food was placed, or could they update this learned response to get the food from a new location?" according to UC Berkeley doctoral student Mikel Delgado. "The squirrels and gerbils tended to go to the original place they had been trained to get food, showing a failure to inhibit what they originally learned."

Out of all the animals tested, primates found far greater success in the test. The study was published in a journal, the Proceedings of the National Academy of Sciences.