The distinctions between a predator's diet, its prey-choice behaviour and its preferences are illustrated in a study of Aelurillus muganicus, a salticid spider from the Apsheron Peninsula in Azerbaijan. Laboratory experiments showed that A. muganicus has an innate predisposition to choose ants as prey. The natural diet of this species was determined by sampling individuals seen feeding in the field (n = 64). Ten arthropod orders were represented. Seven were from the class Insecta (Coleoptera, Collembola, Diptera, Heteroptera, Homoptera, Hymenoptera, Lepidoptera) and three from the class Arachnida (Acari, Araneae, Pseudoscorpiones). Collectively, four orders accounted for >70% of the prey records: Hymenoptera (20%), Lepidoptera (19%), Acari (19%) and Homoptera (14%). No other order accounted for >10% of the prey records. Of the 45 insects among the prey, 13 (29%) were Hymenoptera, with ants (family Formicidae) alone accounting for 24% of the prey records. Although ants were the preferred prey of A. muganicus, as revealed by laboratory testing, and also the most common single category of prey from the field prey records, records of A. muganicus feeding on prey other than ants were actually more common than records of it feeding on ants, suggesting that, besides prey choice, other factors have a strong influence on the diet of this species.

Information on the biology of ‘primitive’ blind snakes can help clarify the origin of ecological traits typical of ‘higher’ snakes. We examined and dissected 360 museum specimens to obtain information on morphology, dietary habits, and reproduction of two subspecies of an African thread snake, Leptotyphlops s. scutifrons and L. s. conjunctus. These small (to 225 mm long), slender-bodied (body diameters < 5 mm) burrowing snakes are common throughout southern Africa. In both subspecies, females grow larger than males and have relatively shorter tails. Reproduction is seasonal, with vitellogenesis in spring (October), oviposition in summer (December–February), and hatching in autumn (April–May). Clutch sizes are small (1–3 eggs), and hatchling thread snakes are large relative to maternal body size. Despite the abundance of termites on the African continent, L. scutifrons feeds almost entirely on the larvae and pupae of small ants. Both races fed infrequently, and took large numbers of prey (up to 350 items) in a single meal. A shift from ‘lizard-like’ to ‘snake-like’ trophic biology is evident within the Scolecophidia: two species of North American thread snake feed frequently on a taxonomically diverse array of small prey; African L. scutifrons feed infrequently on small prey, but take large meals composed of numerous prey items; and one highly derived Melanesian typhlopid (Acutyphlops subocularis) feeds infrequently on large elongate prey. In contrast to popular theory, our data suggest that the evolutionary shift to infrequent feeding among snakes did not initially require a change from small to large prey.

The edentulous giant anteater (Myrmecophaga tridactyla) ingests food using a slender, elongated sticky tongue which can project to a distance greater than the cranial length. A large and elongated hyoid apparatus, including a long stylohyal, epihyal, reduced ceratohyal and fused basihyal-thyrohyal fused to a partially ossified thyroid cartilage, supports the tongue. The fusion pattern and relative hyoid element sizes in adult Myrmecophaga differ from those in other xenarthran anteaters, tree and ground sloths, and armadillos. The hyoid bones have synovial joints with articular surfaces permitting great freedom of movement. A unique hyoid muscle arrangement enables Myrmecophaga to project the tongue with great speed and precise positional control. This muscle arrangement combined with an elongated secondary palate, accommodates the retracted tongue within the oropharynx without compromising the animal's ability to breathe. Maximum gape is reached at a few degrees of mandibular depression, but the oral opening is increased to 2 cm by the extreme length of the anterior facial region. Gape is further increased by medial rotation and depression of the unfused mandibular rami at the mental symphysis. This movement, even without mandibular depression, permits protraction and retraction of the elongated tongue. Mandibular rotation in lieu of depression and elevation simplifies jaw movements made by a smaller uniquely modified muscle mass over shorter distances, therefore increasing the speed with which anteaters can ingest food, and complements the extremely rapid tongue protrusion–retraction cycle.