The Beeholder, January 2009.

the evolution of Hymenoptera (bees wasps and ants)

This is a long but interesting subject and will be
printed in stages in successive issues of the Beeholder.

Recently, fossils of what are thought to be the nests of solitary bees were found in 200-million-year-old petrified wood in Arizona. These are "trace" fossils meaning that only circumstantial evidence, like footprints, rather than fossilized parts of the organism itself were discovered-- so there is some doubt as to whether the galleries bored in the wood were made by bees or by some other insect. Much less questionable is the fossilized bee which was discovered in the late 1980's preserved in a lump of 80-million-year-old amber from what is now New Jersey. That means that the poor creature became mired in the (then) sticky tree sap at a time when the dinosaurs were galumphing about the future sites of Hackensack and Passaic. The dinosaurs played their parts and then faded from centre stage to become modern birds .Today, few people would have trouble distinguishing an archaeopteryx from a flamingo but even to the trained eye the 80-million-year-old bee is remarkably similar to existing species of bees.

Bees were already a well established part of the ecosystem during the hey-day of the dinosaur and had, by this time, developed the biological structures and behaviours necessary to successfully maintain the ecological niche which they still occupy. Although the aforementioned specimen represents the oldest known fossil bee, its highly specialized form indicates that, by the end of the Cretaceous period of the Mesozoic era, bees were already seasoned travellers on the road of evolution (and had already developed sociality) and it is estimated that the first protobee appeared about 125 million years ago-- a time when flowering plants were assuming a more prevalent role in the global ecosystem.

To be continued next issue...