And the honeybee genome has already overturned at least one theoretical prediction: the bee's place of origin. Given that Asia boasts the greatest diversity of bees, ranging from dwarf to giant, many suspected that Apis mellifera began there and spread to Africa and Europe. But tracking mutations--specifically, single nucleotide polymorphisms--entomologist Charles Whitfield of the University of Illinois at Urbana-Champaign has revealed that the honeybee humans know and love originated in Africa. "Certainly the genus itself probably originated in Asia and diversified there," he says. "At some point it got into Africa and then spread back into Europe and Asia." And the genome also proves that a more recent African invasion into the Americas--by the infamous "killer bees"--has proceeded by interbreeding. "Every single bee we looked at in this study was mixed," he notes. "It makes sense that that happened because those honeybees that were first introduced in the Americas were from temperate areas. You introduce this new honeybee from the savanna of Africa, and it is adapted to tropical climates much, much better."

With the genomic map in hand, however, scientists can begin the search for specific genes that control the aggressive behavior exhibited by such Africanized honeybees. More than 50 papers in several journals using the genome are being published concurrently with its revelation in the October 26 Nature. And the ultimate mystery of the hive mind, dictating even down to the level of genetic expression, may eventually be revealed by this work. "My own laboratory is using the genome to help find genes involved in social behavior," Robinson says, "to try to understand the phenomenon of social regulation of gene expression, how social cues act to regulate the activity of genes in the [bee] brain that in turn affect behavior."

Comments