Honeyguide

Honeyguides (family Indicatoridae) are near passerine bird species of the order Piciformes. They are also known as indicator birds, or honey birds, although the latter term is also used more narrowly to refer to species of the genus Prodotiscus. They have an Old World tropical distribution, with the greatest number of species in Africa and two in Asia. These birds are best known for their interaction with humans. Honeyguides are noted and named for one or two species that will deliberately lead humans directly to bee colonies, so that they can feast on the grubs that are left behind.

Description
Most honeyguides are dull-colored, though a few have bright yellow in the plumage. All have light outer tail feathers, which are white in all the African species.

They are among the few birds that feed regularly on wax&mdash;beeswax in most species, and presumably the waxy secretions of scale insects in the genus Prodotiscus and to a lesser extent in Melignomon and the smaller species of Indicator. They also feed on the larvae and on waxworms (caterpillars of Galleria mellonella) in bee colonies, and on flying and crawling insects, spiders, and occasional fruits. Many species join mixed-species feeding flocks.

Honeyguides are named for a remarkable habit seen in one or two species: they guide humans (and more controversially the honey badger in eastern Africa) to bee colonies. Once the hive is open and the honey is taken, the bird feeds on the remaining wax and larvae. This behavior is well studied in the Greater Honeyguide; some authorities (following Friedmann, 1955) state that it also occurs in the Scaly-throated Honeyguide, while others disagree (Short and Horne, 2002). Although most members of the family are not known to recruit "followers" in their quest for wax, they are also referred to as "honeyguides" by linguistic extrapolation.

The breeding behavior of eight species in Indicator and Prodotiscus is known. They are all brood parasites that lay one egg in a nest of another species, laying eggs in series of about five during five to seven days. Most favor hole-nesting species, often the related barbets and woodpeckers, but Prodotiscus parasitizes cup-nesters such as white-eyes and warblers. Honeyguide nestlings have been known to physically eject their host's chicks from the nest and they have hooks on their beaks with which they puncture the hosts' eggs or kill the nestlings.

African honeyguide birds are known to lay their eggs in underground nests of other bee-eating bird species. Scientists have recently found that honeyguide chicks kill the hatchlings of the host nest in brutal attacks using their needle-sharp beaks just after hatching, much like what cuckoo hatchlings do, which are also hatched in other birds nest. The scientists also found that these blind, featherless chicks sometimes are three times heavier than host chicks. According to Dr Claire Spottiswoode, who led the team of scientists, and whose research has been published in the journal Biology Letters, "The honeyguide mother ensures her chick hatches first by internally incubating the egg for an extra day before laying it, so it has a head start in development compared to the host,".

Species
Seventeen species in four genera compose the Indicatoridae.

FAMILY: INDICATORIDAE
 * Genus: Indicator
 * Scaly-throated Honeyguide, Indicator variegatus
 * Greater Honeyguide, Indicator indicator
 * Malaysian Honeyguide, Indicator archipelagicus
 * Lesser Honeyguide, Indicator minor
 * Thick-billed Honeyguide, Indicator conirostris
 * Willcocks's Honeyguide, Indicator willcocksi
 * Least Honeyguide, Indicator exilis
 * Dwarf Honeyguide, Indicator pumilio
 * Pallid Honeyguide, Indicator meliphilus
 * Yellow-rumped Honeyguide, Indicator xanthonotus
 * Genus: Melichneutes
 * Lyre-tailed Honeyguide, Melichneutes robustus
 * Genus: Melignomon
 * Yellow-footed Honeyguide, Melignomon eisentrauti
 * Zenker's Honeyguide, Melignomon zenkeri
 * Genus: Prodotiscus
 * Cassin's Honeybird, Prodotiscus insignis
 * Green-backed Honeybird, Prodotiscus zambesiae
 * Brown-backed Honeybird, Prodotiscus regulus
 * Brown-backed Honeybird, Prodotiscus regulus