Myrmecophagy

Myrmecophagy is a feeding behavior defined by the consumption of termites or ants, particularly as pertaining to those animal species whose diets are largely or exclusively composed of said insect types. Literally, myrmecophagy means "ant eating" (Ancient Greek: murmēx, "ants" and phagein, "to eat") rather than "termite eating" (for which the strict term is termitophagy). However, the two habits often overlap, as both of these eusocial insect types often live in large, densely populated nests requiring similar adaptations in the animal species that exploit them.

Myrmecophagy is found in a number of 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), a number of New World bird species (Antbirds, Antthrushes, Antpittas, flickers of genus Colaptes), and several mammalian groups (anteaters, aardvarks, aardwolves, pangolins, sloth bears, and many armadillos, numbats and echidnas, for instance).

Otherwise unrelated 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. 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 regarded the various species as single order of Mammalia, the Edentata. However it quite early became clear that such a classification was hard to sustain, and there was a growing trend to see the features as examples of convergent evolution. For example, at the start of the 20th century Frank Evers Beddard, writing in The Cambridge Natural History, Vol 10, Mammalia, having discussed some discrepant features, said: "The fact is, that we have here a polymorphic order which contains in all probability representatives of at least two separate orders. We have at present a very few, and these perhaps highly modified, descendants of a large and diverse group of mammals."

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