Among the most remarkable structures in the animal kingdom, the pangolin tongue is an organ of extreme specialisation — long beyond what anatomy seems to allow, coated in mucus of extraordinary stickiness, and anchored in a location that defies anatomical convention. Understanding how the pangolin's tongue works illuminates not only the biology of this unique mammal but also why keeping pangolins alive in captivity presents such formidable challenges for zoologists and conservationists alike.
The pangolin tongue, when fully extended, is longer than the animal's head and body combined in several species. In larger pangolins such as the giant ground pangolin (Smutsia gigantea) of central Africa, the tongue can exceed 40 centimetres in length. South Africa's Temminck's ground pangolin (Smutsia temminckii) typically has a tongue length of 25 to 30 centimetres, which may equal or slightly exceed its head-body length depending on the individual.
This extraordinary length is not achieved by having a simply elongated tongue muscle. The pangolin tongue is a highly modified structure with a complex system of retractor and protractor muscles, and its total extended length significantly surpasses what its jaw dimensions would suggest is possible. The reason for this apparent impossibility lies in where the tongue is actually stored.
Unlike virtually every other mammal, the pangolin's tongue is not anchored at the base of the mouth or the hyoid bones in the throat. Instead, it originates from a cartilaginous structure that lies deep in the chest cavity, passing through the thorax and extending back as far as the pelvic region in the animal's abdomen when fully retracted. This means the tongue, when not in use, is essentially coiled or folded within the body cavity — the only known mammalian example of this anatomical arrangement.
This extraordinary anatomy is made possible by a modified sternum and a highly specialised system of muscles and connective tissue that anchor the tongue's base well behind the ribcage. When the pangolin protrudes its tongue, these muscles contract and extend, pushing the tongue forward and out through the narrow snout at remarkable speed. When the tongue retracts, the entire elongated structure folds back into the body cavity.
The tongue's catching ability depends entirely on mucus rather than on any mechanical grasping structure. Pangolins possess greatly enlarged salivary glands — proportionally far larger relative to body mass than in most other mammals — that produce a thick, highly viscous mucus. This substance coats the entire tongue surface and serves as a biological flypaper: insects that make contact with the tongue are instantly immobilised and adhere to it.
The mucus has been described by researchers as similar in consistency to heavy petroleum jelly — dense enough that insects cannot pull free, yet fluid enough to coat the tongue evenly during rapid extension and retraction. The salivary glands replenish this coating continuously during active foraging. A pangolin foraging for three to four hours through the night may secrete substantial volumes of this mucus over the course of a single feeding session.
Before the tongue ever enters an insect colony, the pangolin must locate its prey. Pangolins rely primarily on their highly developed sense of smell to detect ant and termite colonies. Their olfactory system is sensitive enough to detect the chemical signatures of active insect colonies through several centimetres of soil and through the hardened outer crust of termite mounds.
The tongue itself also plays a role in chemosensory detection. Pangolins will probe cracks, crevices, and soil surfaces with the tongue tip before committing to excavation, effectively tasting the substrate for traces of insect activity. This probing behaviour allows them to assess the density and activity level of a colony before expending the significant energy required to break open a mound or dig down to an underground nest.
Temminck's ground pangolin in South Africa are dietary specialists on ants and termites, but they show clear preferences within that broad category. Studies of stomach contents and field observations indicate that they favour soft-bodied ant and termite larvae and pupae over hard-bodied adult insects, as larvae and pupae provide more energy per unit of volume and are easier to process without teeth.
Among ant genera, Anoplolepis (including the notorious cocktail ant, Anoplolepis custodiens) and Camponotus (carpenter ants) feature prominently in the diet. Harvester termites (Trinervitermes and Microhodotermes species) are important prey items in savanna habitats, while in more arid zones the pangolin targets underground ant nests to a greater degree, particularly during dry season when surface foragers are less abundant.
Finding a colony is only the first step. Pangolins use their powerful forelimb claws — which are among the strongest digging tools in proportion to body size of any African mammal — to break open termite mounds and excavate underground ant nests. The forelimbs deliver rapid, powerful blows that crack even the cement-hard outer crust of mature termite mounds, which can resist the blows of most predators entirely.
Once an opening has been created, the tongue enters the breach. Working at extraordinary speed, it is inserted deep into galleries and brood chambers, withdrawn laden with clinging insects, and the prey is swallowed in a rapid, fluid motion. The tongue may be inserted and withdrawn multiple times per second during peak feeding activity. The entire sequence — excavation, insertion, withdrawal, swallowing — is so rapid that high-speed video has been necessary to analyse the individual stages.
Foraging inside ant and termite colonies poses obvious hazards: soldier insects bite, sting, and spray acid or irritant chemicals. Pangolins have evolved a suite of protective adaptations to manage this threat. Most notably, they can voluntarily seal their nostrils and ear canals when feeding inside a colony — contracting muscular sphincters that prevent insects from entering these vulnerable openings. The thick, overlapping scales on the body, tail, and the outer surface of the forelimbs protect against biting and stinging insects on the body exterior. The scales on the face are smaller and more numerous, offering protection around the snout while still permitting the tongue to operate freely.
Pangolins are the only mammals that are entirely toothless at every life stage — there are no vestigial teeth, no milk teeth, nothing. Food is swallowed whole, and the work of processing prey falls entirely to a highly specialised stomach. The pangolin stomach has muscular walls analogous in function (if not evolutionary origin) to the gizzard of a bird: it grinds ingested prey against small stones and grit that the animal deliberately swallows during foraging.
This grinding mechanism is remarkably effective. Keratinous insect exoskeletons, which are chemically resistant and structurally tough, are broken down in the stomach using a combination of physical grinding and highly acidic digestive juices. Hydrochloric acid concentrations in the pangolin stomach are high, facilitating rapid dissolution of the soft tissues of prey items once the exoskeleton has been mechanically disrupted.
The deliberate ingestion of grit and small stones during foraging is therefore not incidental — it is a behavioural necessity. Pangolins that do not have access to appropriate grit cannot digest prey effectively, a critical challenge in captive settings where substrate choices are limited.
The pangolin stomach combines muscular grinding walls, deliberately ingested grit and small stones, and high-concentration hydrochloric acid to break down insects that have no teeth to masticate them. This system processes hundreds of grams of insects nightly with high efficiency.
A Temminck's ground pangolin in good condition typically consumes between 140 and 200 grams of insects per night, representing several thousand individual ants or termites depending on species size. Extrapolating this across a full year yields a striking figure: a single pangolin may consume in the region of 50 to 73 kilograms of insects annually, which at average insect sizes equates to approximately 70 million individual insects per year.
This appetite makes pangolins a significant ecological force in the landscapes they inhabit. They regulate termite and ant populations, influence soil structure through their excavation activity, and — through their burrowing — create cavities used by numerous other species as dens and nesting sites. The ecological knock-on effects of losing pangolins from a landscape extend well beyond the pangolins themselves.
In the semi-arid and savanna regions of South Africa, prey availability changes markedly between seasons. During the wet season (roughly November to March in most of the Temminck's ground pangolin range), termite alates (winged reproductives) emerge in massive numbers, surface-foraging ant colonies are highly active, and the soil is soft enough to excavate easily. This period tends to support the highest feeding rates and the fastest body condition improvement in pangolins.
During the dry season, surface activity by ant and termite colonies drops substantially. Pangolins respond by shifting their foraging strategy — spending more time excavating deeper underground nests, targeting ant species that maintain active colonies underground even in dry conditions, and sometimes ranging more widely to find sufficient prey. Foraging nights may extend in duration, and energy expenditure per unit of prey consumed increases. This seasonal variation in feeding success has important implications for body condition heading into the mating season and for the nutritional demands of pregnant and nursing females.
The extraordinary specialisation of the pangolin tongue and digestive system that makes it such an effective wild forager creates near-insurmountable challenges in captivity. The core difficulties are:
These challenges explain why conservation organisations working with pangolins consistently emphasise rapid return to the wild after veterinary treatment rather than long-term captive holding. The pangolin tongue and its associated biology are magnificently adapted to life in the wild — and only there.
The pangolin tongue is one of evolution's most elegant solutions to a specific ecological niche: an organ so long it must be stored partly in the body cavity, coated in industrial-grade sticky mucus, operated at extraordinary speed, and paired with a toothless gizzard-style stomach that grinds prey against deliberately ingested grit. Together, these adaptations allow a single Temminck's ground pangolin to consume around 70 million insects per year, making it both a biological marvel and an ecologically vital part of southern Africa's savanna systems.