The sunbirds and spiderhunters make up a family, Nectariniidae, of very small passerine birds. There are 132 species in 15 genera. The family is distributed throughout Africa, the Indian subcontinent, Southeast Asia and just reaches northern Australia. Most sunbirds feed largely on nectar, but also take insects and spiders, especially when feeding young. Flower tubes that bar access to nectar because of their shape, are simply punctured at the base near the nectaries. Fruit is also part of the diet of some species. Their flight is fast and direct on their short wings.
The sunbirds have counterparts in two very distantly related groups: the hummingbirds of the Americas and the honeyeaters of Australia. The resemblances are due to convergent evolution brought about by a similar nectar-feeding lifestyle. Some sunbird species can take nectar by hovering like a hummingbird, but they usually perch to feed. source