The ability to move quickly is necessary for survival in the animal kingdom, particularly for lagomorphs, which includes both rabbits and hares. These small herbivores are prey for a wide range of predators, making a rapid and effective escape mechanism essential. The incredible speeds achieved by these animals are a direct result of evolutionary pressure to evade capture. The speed of these leporids is not uniform, however, and depends significantly on the specific species and the biological machinery propelling them.
The Maximum Recorded Speed
The fastest members of the lagomorph family are the hares, particularly the various species known as jackrabbits, which inhabit open plains and rely on sheer velocity to escape. The maximum recorded speed for the fastest lagomorphs is approximately 45 miles per hour (72 kilometers per hour) over a short distance. This top speed is typically attributed to the Black-tailed Jackrabbit and similar hares, which must outrun predators like coyotes and eagles in environments with minimal cover. This benchmark speed represents a sudden acceleration used to gain distance and break the line of sight from a pursuer. For comparison, an Eastern Cottontail, a true rabbit that relies more on nearby cover, reaches a top speed closer to 30 to 35 mph (48 to 56 kph).
Factors Influencing Rabbit and Hare Velocity
The variation in recorded speeds is largely explained by the biological distinction between rabbits and hares. Hares, such as the jackrabbit, are built for speed in open environments, featuring longer limbs and a leaner physique. They rely on their top speed to outrun danger over long distances, sometimes sustaining speeds up to 35 mph (55 kph).
True rabbits, like the cottontail, have shorter legs and typically inhabit areas with dense cover, such as forests and brush. These animals are not built for prolonged, high-speed sprinting; instead, their escape strategy favors a burst of speed coupled with an immediate dive into a burrow or thicket. Domesticated rabbits, which descend from the European rabbit, are often slower and less agile due to centuries of breeding for companionship.
Another factor is the duration of the run, as the top speed can only be sustained for a brief period before fatigue sets in. A hare’s maximum velocity is a short-term tool. The type of terrain also plays a role, with hares performing best on flat, open ground where their powerful stride is unimpeded, while rabbits’ agility allows them to better navigate uneven or brush-filled landscapes.
Biological Mechanics of High-Speed Movement
The extraordinary speed of lagomorphs is an outcome of specific anatomical and physiological adaptations. The disproportionately long and muscular hind legs function as powerful levers for propulsion. These limbs are packed with a high concentration of fast-twitch muscle fibers, the same tissue responsible for the rapid, forceful contractions seen in human sprinters.
The animal’s gait, known as saltatorial locomotion or bounding, is highly specialized, allowing for maximum stride length. When running at high speed, the flexible spine acts like a spring, bending and extending to increase the distance covered with each leap. The long tendons in the legs also contribute significantly, storing elastic energy upon landing and releasing it to power the next bound, making the movement efficient.
Equally important to pure speed is the ability to rapidly change direction, often described as a zigzagging pattern. This calculated survival mechanism forces a predator to constantly adjust its trajectory, causing it to lose momentum or overshoot the target. A large heart and lung capacity for rapid oxygen delivery, combined with an extremely fast reflex system, allows the lagomorph to process the visual threat and execute a sharp turn in milliseconds.