Squirrels May Favor Left or Right Paws

A study conducted by the University of Exeter in January 2020 revealed that squirrels with a strong preference for one paw, either left or right, tend to perform worse in learning tasks. Wait, what? That raises so many questions.

First, how did scientists determine that squirrels have a preferred side (referred to as lateralization)? Additionally, once they identified the preferred paw, how did they link it to intelligence or performance? And most importantly, what does this imply? Can researchers genuinely establish a meaningful connection between lateralization and learning abilities in squirrels, or even humans? Let’s dive deeper.

Similar to humans, many animals tend to prefer one side of their body for specific activities. For instance, if you ask your dog to shake, it might consistently present its left (or right) paw. The likelihood of this behavior depends on the animal's level of lateralization.

Dr. Lisa Leaver, the program director of the Master Science Exeter Animal Behavior program, notes that certain research indicates lateralization enhances brain efficiency by allowing each hemisphere to specialize in specific tasks.

"This could enhance an animal's chances of survival," Leaver stated in a news release, "which might clarify why lateralization has evolved throughout the animal kingdom."

She mentioned that studies on fish and birds show strong lateralization correlates with improved brain function, but "data from mammal studies is limited and suggests a weak or even inverse relationship."

Leaver and her team aimed to determine if a strong preference for one side was linked to lower cognitive abilities, using gray squirrels from Exeter's Streatham Campus as their test subjects.

During the experiment, squirrels were tasked with retrieving peanuts from a narrow transparent tube. While squirrels usually use their mouths to grab food, the tube's width made this impossible, forcing them to rely on their paws. Researchers observed over 30 squirrels, gathering sufficient data from 12 subjects to analyze how quickly each squirrel solved the task (evaluating learning) and whether they showed a paw preference (assessing lateralization).

The findings revealed that squirrels with a strong paw preference were less adept at learning, which seems surprising given the problem-solving nature of the task. Intriguingly, some studies suggest that ambidextrous individuals (those without a dominant hand) may exhibit greater creativity. However, squirrels might challenge this notion.