No, it’s not a circus trick. This is how Sauteur d’Alfort rabbits actually get around.

Image credit: Carneiro et al, PLoS Genetics

A rabbit doing a handstand and walking around like that? Indeed, a rare domesticated breed known as Sauteur d’Alfort rabbits have ditched hopping in favor of this rather bizarre method of moving about. They walk along on their front paws in this position seemingly without much trouble.

Saltatorial locomotion is the normal gait of rabbits, and also that of kangaroos, hares, and some rodents. A new research study published in the journal PLOS Genetics aimed to pin down why this particular breed of rabbit exhibit saltatorial locomotion, so the researchers bred some with regular hopping rabbits to find out. Then, they compared the genotypes of their offspring and investigated how this influenced their phenotype (handstand or jump). In the end, they were able to identify one particular gene mutation that is responsible whether the bunny hops or not.

More precisely, the handstand developmental defect was found to be centered around a specific mutation in the RAR related orphan receptor B (RORB). While with hopping rabbits, the RORB protein is common across their entire nervous system, the mutation slashed the number of neurons in the spinal cord that produce RORB, resulting in the Sauteur d’Alfort’s unique way of walking.

“This study provides a rare example of an abnormal gait behavior mapped to a single base change and the first description of a gene required for saltatorial locomotion,” the authors said in a statement. “It further demonstrates the importance of the RORB protein for the normal wiring of the spinal cord, consistent with previous studies in mouse.”

It is also very spectacular, to say the least. And, fortunately, it’s unlikely to cause the animals any pain.