The pangolin is often described as a walking artichoke due to its dense covering of scales. This unusual appearance frequently leads to confusion, as many observers mistake it for a reptile or an armadillo, even though it is classified as a mammal. The prominent, hard armor covering the majority of its body raises questions about the presence of typical mammalian traits, such as hair.
The Answer: Where Pangolins Have Hair
The simple answer is that pangolins do have hair, which firmly establishes their classification as mammals. While the dorsal side is almost entirely covered by thick, overlapping scales, hair is concentrated in the areas that lack this armor. Soft, pale hairs are found primarily on the animal’s underside, including the belly, chest, and the inner parts of the limbs. These regions are kept scale-free so the animal can roll into a tight, protective ball, shielding its vulnerable parts inside the armored exterior.
Hair is also typically present on the pangolin’s snout, around the eyes, and ears, where scales would impede sensory functions. Furthermore, in most Asian pangolin species, small tufts of hair, often called bristles, grow out from the skin between the large scales on the back and tail. This inter-scale hair is sometimes absent in African species, showing a slight anatomical variation across the eight pangolin species. The presence of hair confirms the pangolin’s identity as a mammal, despite its extensive scaled covering.
Understanding Pangolin Scales
The scales are a fascinating biological adaptation, made entirely of keratin. Keratin is the same fibrous structural protein that forms human hair and fingernails, making pangolin scales structurally different from the scales found on reptiles like snakes or lizards.
These hardened, plate-like structures cover the pangolin’s body from head to tail, sometimes making up as much as 20% of its total body weight. The scales grow continuously throughout the animal’s life and are constantly worn down as the pangolin moves and digs through soil. When threatened, the pangolin curls into a nearly impenetrable ball, using the sharp-edged scales as an effective suit of armor against predators.
The evolutionary origin of this unique armor is not fully understood, but it is considered a specialized mammalian adaptation, not a shared feature with reptiles. This unique combination of hair on the belly and keratin scales on the back makes the pangolin the only mammal in the world to be covered in such extensive, overlapping scales.