Pangolins, the only mammals covered in protective keratin scales, possess an unusual method of movement. They are facultatively bipedal, meaning they walk on two legs only in certain circumstances. This makes them one of the few mammals, alongside humans, that can exhibit an alternating two-legged gait. Pangolins do not rely on two legs for all travel, but choose this upright stance when it offers a distinct advantage.
Pangolin Locomotion: Quadrupedalism vs. Bipedalism
Despite the striking image of an upright pangolin, their primary and most common mode of travel remains quadrupedal, utilizing all four limbs. Ground-dwelling species, such as the Temminck’s ground pangolin, often move with a distinctive “knuckle-walking” gait. They curl their long, specialized digging claws inward, walking on the knuckles and the pads of their forefeet to protect the sharp keratin from being worn down on rough terrain.
This four-legged movement is the most energy-efficient method for covering long distances, especially given the weight of their heavily armored scales. Arboreal species, like the white-bellied pangolin, spend most of their time climbing, relying on their strong forelimbs and prehensile tails to navigate tree branches. Bipedalism is an alternate form of locomotion employed strategically.
The Unique Posture of Upright Pangolin Movement
The mechanics of bipedal movement rely heavily on the pangolin’s tail. The tail is thick, long, and heavily muscled, functioning as a counterbalance to stabilize the torso when the animal stands upright. As the pangolin lifts its body and forelimbs off the ground, the tail extends backward, acting like a dynamic tripod support.
The bipedal gait involves an alternating movement of the hind legs, though the pangolin maintains a different center of gravity than humans. The forelimbs, equipped with powerful claws optimized for tearing apart termite mounds, are held high off the ground or tucked close to the chest. Freeing the front limbs from weight-bearing duty allows the pangolin to move without dulling its primary tools for foraging and defense.
Situational Triggers for Two-Legged Walking
Pangolins adopt their upright posture in response to specific environmental or behavioral cues, not for general travel. One reason for walking on two legs is to survey the immediate environment. Standing taller provides an elevated perspective, helping the pangolin locate food sources or detect approaching threats in tall grass.
This movement is also employed when the animal needs urgency, as bipedalism allows for a faster burst of speed over short distances than their typical knuckle-walk. When carrying materials, such as food or nesting supplies, the bipedal stance frees the forelimbs for manipulation and transport. The upright posture can also serve as a defensive display, making the pangolin appear larger before it curls into its protective ball.