Bees are the predecessors of wasps in the family Crabronidae, that are predators of other insects. Change of feeding on insect prey to pollen is as a result of the consumption of prey insects which visited flowers and were partly covered with pollen when they were used as a source of feed to the wasp larvae. This same evolutionary scenario may have occurred within the vespoid wasps, where the pollen wasps is as a result of evolution from predatory ancestors. Until recently, the oldest non-compression bee fossil had been found in New Jersey amber, Cretotrigona prisca of Cretaceous age, a corbiculate bee. A bee fossil from the early Cretaceous (~100 mya), Melittosphex burmensis, is considered "an extinct lineage of pollen-collecting Apoidea sister to the modern bees". …show more content…
They are closely related to wasps but are different by having branched or plume-like setae (hairs), combs on the forelimbs for cleaning their antennae, small anatomical differences in the limb structure and the venation of the hind wings, and in females, by having the seventh dorsal abdominal plate divided into two half-plates. Pertaining to behaviour, a major characteristic of bees is that they collect pollen to provide provisions for their young, and have the necessary adaptations to do this. However, some wasp species such as pollen wasps have similar behaviours, and a few species of bee are scavengers in which they utilitize their catch to feed their offspring. The world's largest species of bee is known to be the Indonesian resin bee Megachile pluto, whose females can attain a length of 39 millimetres (1.54 in). The smallest species may be dwarf stingless bees in the tribe Meliponini whose workers are less than 2 millimetres (0.08 in) in length. A bee possesses a pair of large compound eyes which cover much of the surface of the head. Between and above these are three small simple eyes (ocelli) which is used to gather information for the bee on light