Scientists Attribute Mules’ Intelligence to “Hybrid Vigour”

It is just a given to know that mules are smart. They are described as highly intelligent, even. This is something that those in the mule industry have known for years, and now the scientific community has done a study to prove it.

This study, done by Leanne Proops at the University of Sussex in Brighton, UK, compared the behavior of mules to that of its parents and focused on “hybrid vigor,” or where the best genes of parent species “mix and match” to produce superior traits in a hybrid.

It is already known that mules show signs of hybrid vigor in their physical characteristics. “Mules tend to be stronger and have better endurance than a horse, combined with the steadfast disposition and sure-footedness of the donkey,” said Proops. “Mules are capable of growing taller than either parent and of carrying more weight than a horse of the same size.” But how being a hybrid affects their intelligence had not been studied before.

Over 25 sessions, six mules, six ponies, and six donkeys were presented with two buckets marked with black and white symbols. They had to pick the “correct” bucket to get the carrot inside. Once they passed the test, they switched the symbols and started again.

The mules learned significantly more pairs of symbols than their parents. “Mules outperformed both ponies and donkeys in the visual discrimination task,” said Proops. “The mules learned 16 pairs, the ponies 11 and the donkeys 6.”

The study only proves what so many of us owning, training, raising and/or riding mules have known and for years have shouted to those who would listen.

Click here to see the study.