July 29, 2015 by wagnerfreeinstitute
Scientific name: Osmia avosetta
Size: 1 cm
Range: Turkey through the South Caucasus into Iran
While bees are best known as colonial insects, some species have taken to a solitary life. Without the aid of an entire colony’s worth of worker bees, mating females of these species must craft their own ways of protecting their young.
One species in particular, Osmia avosetta, has devised a nest that is both practical and beautiful. O. avosetta belongs to a family called mason bees, so named because they use mud to build nests within hollow spaces. O. avosetta takes this a step further by first lining a 1.5 cm deep burrow with overlapping flower petals, creating a shingled appearance. Then, within that, she lays down a thin layer of mud, and at last one more layer of flower petals, effectively forming a petal sandwich. The mother then stocks the chamber with pollen and nectar and lays an egg on top of the pile of provisions. Finally, she seals the top of the nest by folding the petals inwards and plugging the hole with mud. This allows for a humid interior to protect the larva in dry conditions, while allowing for the exterior to dry into a hard shell.
O. avosetta appears to be oligolectic (preferring only one species) in its choice of flower: Hedysarum elymaiticum. Despite this beautiful and ingeniously crafted fortress, one foe comes in the form of a parasitic wasp that lays its eggs in the chamber. Once hatched, the wasps devour the bee larva and feast on its stash. In a strange coincidence, this behavior was observed for the first time by two separate unrelated teams of scientists on the exact same day, one in Fars Province, Iran, and the other in Antalya Turkey.
For more stunning pictures of these bees and their “artsy” nests, read this National Geographic article.