Animals with Bigger Brain Size Have More Self Control [VIDEO]

A study of 36 species of mammals and birds found that animals with bigger brain size display more self control.

The mystery of human cognitive evolution is most remarkable when it comes to comparing humans with chimps, a closely related species. There are certain cognitive traits that humans share with other animals. Yet what is unknown is how these traits evolved.

In a latest collaborative study scientists at Duke University and University of California, Berkeley,  looked at self control in animals. They say that brain volume and not body size helps determine self control in animals.

The researchers observed that chimps have more self control than fox squirrel or gerbils. The researchers define self control as the ability to restrain strong but counter-productive behavior.

They based their conclusion on a series of food foraging experiments. These experiments made it clear that animals with bigger brains showed superior cognitive powers. Apart from this, the animals that had mixed diets had the highest level of self control.

Throwing light on the association between bigger brain size and self control, the researchers assume that as the brain gets bigger, the number of neurons also increase due to which the brain tends to get more modularized hinting towards the evolution of new cognitive network.

First Experiment Using Tube as Bait:

The first experiment was done on a variety of creatures both small and large. The researchers tested the animals to see if they proceeded toward a transparent cylinder that had food, displaying a lack of self control, after the animals were trained to gain access to the food through a side opening in an opaque cylinder.

The researchers saw that primates such as gorillas showed good self control whereas animals with smaller brain size produced mixed results.

In another study, researchers experimented with campus fox squirrels and some Mongolian gerbils and put them through some food foraging tasks.

The fox squirrels were made to watch how the food was placed in an opaque cylinder. They were shown the place from where they had to enter the cylinder. After this demonstration, the food was transferred to a transparent cylinder. They noticed the squirrel's movement, if the squirrels directly attacked the food inside the cylinder; they failed to display self control. But if they approached the food through the right direction, that meant they had greater self control.

"About half of the squirrels and gerbils did well and inhibited the direct approach in more than seven out of 10 trials," UC Berkeley doctoral student Mikel Delgado said. "The rest didn't do so well."

Second Experiment:

In next test, the researchers placed three cups A,B and C in a row in a way that the animals could clearly see which cup had food placed in it. The food was mostly placed in cup A. Next the researchers turned the cups upside down so that the 'baited' cup was not visible to the animals.

The animals moved to the next level only if they successfully touched the cup that had food thrice in a row. The researchers then changed the food to cup C, which was placed at the end of the row.

"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?" Delgado said. "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."

"It might be that a squirrel's success in life is affected the same way as in people," UC Berkeley psychologist Lucia Jacobs, a co-author of this study said. "By its ability to slow down and think a bit before it snatches at a reward."

The finding was documented in the Proceedings of the National Academy of Sciences.