Scientists crack bee code to honey pot

She has a biological clock to tell the time of day, uses a sophisticated navigation system to locate food miles away and can produce the sweetest natural substance on earth simply by chewing up pollen grains.

The secret life of the honey bee is about to be revealed after the success of an international effort to decipher the full genetic recipe of the most economically valuable insect.

Scientists have published the results in the journals Nature and Science.

An early analysis of the genes has shown that the honey bee's ancestors originated in Africa and migrated at least twice in the distant past to populate Asia and Europe.

Another finding is that the honey bee has an unusually high number of genes devoted to smell, making her better at detecting a scent in the air than fruit flies or mosquitoes.

Scientists hope that more secrets will be explained at the molecular level with the help of the full DNA sequence of the only social insect to be partially domesticated by man.

A study of the bee's genome has shown that the molecular machinery of its internal body clock more closely resembles that of a mammal than of other insects, said Guy Bloch of the Hebrew University in Jerusalem.

The bee can learn to reach flowers at nine different times of the day with an accuracy of 20 minutes. The clock is essential for its navigation system - based on the movement of the sun in the sky - which can locate a food source up to 9.6km away.

"Discovering that molecular characteristics of the biological clock in bees is closer to the biological clock of mammals than that of flies was a big surprise," Dr Bloch said.

Scientists also announced the discovery of the world's oldest bee, a 100-million-year-old specimen preserved in amber that had evolved from a wasp-like ancestor. It was about 40 million years older than the previous oldest known bee fossil.

Honey bees evolved millions of years later alongside flowering plants in a symbiotic relationship, said Hugh Robertson, professor of entomology at the University of Illinois at Urbana-Champaign.

Today bees pollinate billions of dollars worth of agricultural crops.

"Foraging worker bees might encounter a bewildering number of flowers to choose from, but they can discriminate between them using subtle olfactory cues," Professor Robertson said.

Gro Amdam of Arizona State University in Tempe, Arizona, said scientists had hoped that the honey bee genome would also explain how it evolved into being a social insect with a caste of sterile female workers, male drones and a fertile queen.

"However, we didn't find much diversification of such social genes."

The scientists hope that by selectively silencing certain honey bee genes they will be able to work out which ones are involved in the genetic programming necessary for the evolution of castes within the hive.


Honey bees

* Some 20,000 bee species exist, on every continent except Antarctica.
* They carry an electrostatic charge, which helps pollen stick to their bodies.
* Despite their sometimes painful sting, bees are one of the few insects used on advertisements, mostly to promote honey.

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