Bees are winged hymenopteran insects in the clade Anthophila. While around ninety percent are solitary animals, the remainder are well-known for their eusocial habits, living in colonies that can contain thousands of insects with social roles designated at birth. There are around 16,000 species of bee, and they inhabit every part of the world that contains flowering plants; Antarctica is the only continent where they are not found. The diets of most bees consists of nectar and pollen; they are highly specialized for feeding from flowers, and many flower species have coevolved with bees for millions of years. The first bees in the fossil record are known from about 100 million years ago, during the late Cretaceous period. The smallest members of this group are workers of certain stingless bee species (tribe Meliponini), reaching only two millimeters in length. The largest is Wallace’s giant bee (Megachile pluto) which, with females reaching over 1.5 inches long, is a veritable beehemoth.
