Anteaters look for food through smells, and their vision may be poor. Large anteaters eat large clusters of ants and termites. Anteaters feed quickly, usually digging a hole in the nest and licking the worker ants as they dive, while eating the larvae and eggs at a rate where their tongue moves 150 times per minute. The insect was glued to the saliva-covered tongue, then slammed into the hard palate, and finally swallowed into the abdomen. Anteaters will hide from large jaw ants and soldier ants in termites.
Due to the thick skin on the nose and mouth, it is clear that it is not affected by the bite of soldier ants. And they spend a short time in each nest, eating only about 140 ants per meal (only 0.5% of their daily food requirement). Anteaters rarely cause permanent damage to nests. Their fate seems to be closely linked to the number of nests in an area, and in order to get enough nutrients, they visit some nests every day (adding up to a total of 35,000 ants a day). They also eat the larvae of beetles and get water from their food.
Of all mammals, anteaters eat in a unique way. They shrink the chewing muscles, rolling the two halves of the jawbone into the middle, so they can separate the front tip and open their mouths. The wingbones muscles stretch the back of the two inward-facing jawbones, raising the front tip to the position of the mouth so that the mouth can be closed. The result is simpler and less movement of the jaw, with the tongue moving in and out and almost non-stop, allowing for maximum intake of food at a time.
The two small anteaters specialize in eating small termites and ants, and, like large anteaters, avoid soldier ants. They also do not eat termite species with chemical defenses, but do eat bees and honey. A small anteater usually eats 9,000 ants a day. Two-toed anteaters feed on ants and termites that average 4 mm in length in trees, while large anteaters eat prey of 8 mm or larger.
Usually all species of anteaters live alone. The territory of the great anteaters may be only 0.5 hectares in food-rich areas, such as the tropical forests of Baro Clunado Island in Panama or in the highlands of southeastern Brazil. In areas with fewer ant and termite nests, such as Venezuela's mixed deciduous forests and semi-arid savannahs, a large anteater may need a territory of up to 24.8 square kilometers.
There may be a 30% overlap in the range of action between female large anteaters, compared with less than 5% between male large anteaters. The two small anteaters are less than half the size of the large anteaters and have the same good habitat as Baroclonado Island, each with a territory of about 0.5 to 1.4 square kilometers. In the vast prairie, a small anteater requires an activity range of about 3.4 to 4 square kilometers. The territory of female two-toed anteaters on Baro Clunado Island averages 2.8 hectares, compared with about 11 hectares per male individual, whose range overlaps with that of both females, but not with neighboring male individuals. Although the geographical distribution of the four anteaters is not the same, when they appear in the same habitat, the territory of each individual does not appear to be affected by the appearance of other individuals.
Large anteaters and two small anteaters mate in the fall, and cubs are born in the spring. The large anteaters stand and give birth, using their tails as a third support besides their hind legs. Newborn pups are precocious and have sharp claws, allowing them to grasp the back of the female shortly after birth. It is rare for a litter of two cubs to pass through about 6 months of lactation, but may follow the mother until the age of two until they reach sexual maturity. The cubs of large anteaters grow violently within the first month of life, but are generally slow to move and are carried on the back of the mother. Two small anteaters may place their pups on a branch next to their preferred feeding site or place them in a leaf nest for a short period of time; the same will be true for two-toed anteaters. Two-toed anteaters feed their young animals semi-digested ants, and both males and females provide this ruminant food, and the young animals may be carried and fed by their father or mother. The young, large anteaters are the epitome of their parents, while the young little anteaters do not resemble their parents.