The Architecture of Armor
Pangolins are the only mammals whose bodies are covered in large, overlapping scales. These scales are not like those of a reptile. Instead, they are composed of keratin—the same structural protein found in human fingernails and hair. The scales are essentially agglutinated, or fused, hairs. They are soft on newborn pangolins, called pangopups, but quickly harden as the animal matures. This flexible armor originates from the thick skin and grows continuously throughout the pangolin's life.
The scales' internal structure is a crossed-lamellar arrangement of keratinized cells, which provides both strength and flexibility. This design makes the scales remarkably durable against predators like lions and leopards. Four species of pangolin live in Uganda: the giant ground pangolin (Smutsia gigantea), the white-bellied pangolin (Phataginus tricuspis), Temminck's ground pangolin (Smutsia temminckii), and the black-bellied pangolin (Phataginus tetradactyla). The giant ground pangolin, true to its name, is the largest species, reaching up to 33 kg. The smaller, tree-dwelling white-bellied pangolin weighs only 1-3 kg.
A Specialized Existence
When threatened, a pangolin’s primary defense is to roll into a tight, nearly impenetrable ball, tucking its un-scaled face and soft underbelly beneath its armored tail. Muscles allow the animal to erect its scales, creating a sharp, cutting surface to deter predators. Some ground-dwelling species can also swing their tails like a club, using the sharp-edged scales as a weapon.
This armor is important for a toothless mammal. Pangolins are myrmecophagous, meaning their diet consists almost entirely of ants and termites. A single pangolin can consume up to 70 million insects in a year, using powerful front claws to tear open nests. Its tongue is biologically unique; it is not attached in the throat but anchors deep in the chest cavity near the pelvis. This allows the sticky tongue to extend up to 40 cm in larger species—sometimes longer than the animal's head and body combined. To survive without teeth, pangolins ingest small stones and sand that accumulate in a muscular part of their stomach, called a gizzard, to grind up their food.
The unique biology of the pangolin is directly linked to its greatest threat. The keratin scales are highly valued in some traditional medicines, despite having no proven therapeutic properties. This demand, along with consumption of their meat, drives a massive illegal trade, making them the most trafficked mammals in the world. Between 2015 and 2024, authorities seized over 370 metric tons of pangolin scales originating from Africa.