Mules Smarter Than Ponies
A study of equine intelligence has confirmed what many mule handlers have long suspected: compared to their donkey and horse parents, mules learn quickly.
In their investigation of how readily these animals learn, researchers from the United Kingdom tested mules, ponies and donkeys.
Each animal was repeatedly shown two food buckets, distinguished by different painted symbols. The equines needed to choose which one of these buckets consistently offered a food reward.
The mules outshone their competitors on two fronts. Over the course of the study, the mules figured out where the food was among more bucket pairs than did the ponies or donkeys. As well, the mules were the only equines to learn more rapidly as the study proceeded. It took the mules progressively fewer trials to correctly choose between bucket pairs.
The researchers attribute their results to "hybrid vigour". Mules are a cross between two species, resulting from breeding a male donkey with a female horse or pony. Mules physically display hybrid vigour with height and strength that's often greater than their parents. This study is the first to demonstrate that hybrid vigour also includes enhanced cognitive abilities.
Leanne Proops, Faith Burden and Britta Osthaus. 2009. Mule cognition: a case of hybrid vigour? Animal Cognition. 12(1): 75-84.