# Myrmecophagy

Myrmecophagy is a feeding behavior in animals, defined by the consumption of termites or ants—particularly as pertaining to those animal species whose diets are largely, or completely, composed of these insect types. Notable myrmecophages include the giant anteaters and tamanduas, some armadillos, and pangolins, as well as some members of the order Carnivora such as the sloth bear of the Indian subcontinent and the aardwolf of Southern Africa.
Myrmecophagy means "ant-eating" (Ancient Greek: murmēx, "ants", and phagein, "to eat"); the related habit of termite-eating is termitophagy. The two dietary habits often overlap, as these eusocial insects live in large, densely-populated, terrestrial ant colonies or termite mounds, requiring specialised adaptations from any species that wishes to access them. Physical traits of myrmecophagous animals include long, sharp, often curved frontal claws for digging into nests or mounds.

## Vertebrates

Myrmecophagy is found in several land-dwelling vertebrate taxa, including reptiles and amphibians (horned lizards and blind snakes, narrow-mouthed toads of the family Microhylidae and poison frogs of the Dendrobatidae), some New World bird species (Antbirds, Antthrushes, Antpittas, flicker of genus Colaptes), and mammalian groups including anteaters, aardvarks, aardwolves, armadillos, echidnas, numbats, pangolins, and sloth bears.
Other animals not typically thought of as myrmecophagous—but which actively seek-out and consume these insects—include the sun bear of Southeast Asia (along with most other bear species), chimpanzees and other primates, along with many birds, reptiles and amphibians.
The extinct alvarezsaurids, a group of theropod dinosaurs from the Cretaceous period, have been interpreted as myrmecophagous, with their short, robustly built arms with a single claw being interpreted as being used to break into colonial insect nests.
Mammals that specialize in myrmecophagy often display similar adaptations for this niche. Many have powerful forelimbs and claws adapted to excavating the nests of ant or termite colonies from the earth or from wood or under bark. Most have reduced teeth and some have reduced jaws as well. Many have low basal body temperatures, an adaptation to the low energy content of ants and termites, and most have advanced olfaction to help them find prey. Practically all have long, sticky tongues. In the nineteenth and early twentieth century many zoologists saw these shared features as evidence of relatedness, and accordingly they classified the various species as a single order of Mammalia, the Edentata. It quite early became clear that such a classification was mistaken, and the features came to be seen as examples of convergent evolution, for example, by Frank Evers Beddard in 1902. As genome sequences for various former members of Edentata have been published, genetic evidence has confirmed that its members are taxonomically distant.

## Invertebrates

Ants are dangerous, small, and rich in distasteful and harmful compounds, making them difficult prey and favouring ant mimicry for defence among invertebrates. Ants are plentiful, so members of several invertebrate taxa do feed on ants. Such ant predators include some spiders, such as species in the family Salticidae (jumping spiders), spiders in the family Oecobiidae and the family Theridiidae. While exclusive myrmecophagy is not very common, there are some striking examples, such as the Australian ant-slayer spider Euryopis umbilicata that feeds almost exclusively on one species of ant. Other examples include some myrmecomorphs (ant mimics) and myrmecophiles. Myrmecomorphs are Batesian mimics, giving them protection against predators which avoid ants, and access to abundant food.
Various Hemipteran bugs, in the family Reduviidae feed largely or exclusively on ants. Examples include the genera Paredocla and Acanthaspis.
Some insects that feed on ants do so because they are opportunistic predators of small insects that run on the ground surface, of which ants are a large proportion. Remarkable examples of convergent evolution are certain species of the Neuropteran family Myrmeleontidae, largely Myrmeleon, the so-called ant lions, and the Dipteran family Vermileonidae, in particular the genera Lampromyia and Vermileo, the so-called worm lions. Both of them are regarded with interest for their habit of constructing conical pit traps in fine sand or dust, at the bottom of which they await prey that has fallen in. Both throw sand to interfere with any attempts on the part of the prey to escape.
Myrmecophagy takes more forms than just eating adult ants; the later instars of caterpillars of many butterflies in the family Lycaenidae enter the nests of particular species of ants and eat the ants' eggs and larvae. Larvae of some species of flies, such as the genus Microdon in the family Syrphidae spend their entire immature lives in the nests of ants, feeding largely or entirely on the ant brood. Some beetles specialise in feeding on the brood of particular species of ants. An example is the coccinellid Diomus; larvae of Diomus thoracicus in French Guiana specialise in the nests of the invasive ant species Wasmannia auropunctata.
Major predators of ants include other ants, especially the army ants and their close relatives. Some ants such as the raider ant Oocerea biroi and the new world army ant Nomamyrmex esenbecki are obligate myrmecophages, that is they eat exclusively other ants, while the swarm-raiding Eciton burchellii eat more or less all arthropods in their paths, including other ants. Primarily it is the pupae and larvae, rather than adult ants, that are eaten.