Mechanics of a kangaroo rat (D. deserti) escape response 

Kangaroo rats use erratic vertical leaps – over ten times hip height - to evade snakes. These high-performance behaviors are fascinating as they seem to challenge muscle power limits at take-off, and as their tails is suggested to help them to not only stabilize, but also maneuver while airborne. Within animal models, muscle power often presents a limit to mechanical performance. Maximal kangaroo rat jumps are suggested to require more power than muscles alone can provide. Kangaroo rats achieve these high-power outputs using their ankle extensor tendon in two distinct ways, simultaneously: by transferring energy from thigh and back muscles, and by storing elastic energy while decoupling muscle fascicle shortening velocities in calf muscles from ankle flexion, allowing these muscles to operate under near optimal conditions for power production. Also, tails play a key role in the outcome of these predator-prey interactions as they influence aerial re-orientation of the body.

Dr. Janneke Schwaner