for National Geographic News
Scientists have sequenced the honeybee genome, revealing some of the biology beneath the insects' advanced social systems and powerful sense of smell as well as the spread of Africanized (or "killer") strains.
The study, which paves the way for a new era of bee research, marks the third insect genome to be sequenced, after the fruit fly and the mosquito.
Scientists have long wanted to know what makes the honeybee—Apis mellifera—tick, because it serves as a model for social behavior and because of its vital worldwide role as a pollinator (honeybee photos, facts, and more.
Honeybees form elaborate hives and divide into complex social strata, and some honeybees have even learned abstract concepts such as "same" and "different" in the lab.
But honeybee brains contain only a million neurons. That's a hundred thousand times fewer cells than human brains and only four times more than a fruit fly's.
The new genome research doesn't disappoint.
"I don't want to go so far as to say it's done a better job of evolving," said Kim Worley, a researcher at Baylor College of Medicine in Houston, Texas, and one of the study co-authors. "The honeybees have got a lot of interesting biology, and we're seeing genes that can explain some of it."
A paper summarizing the research, which was led by George M. Weinstock, also at Baylor College of Medicine, will appear in tomorrow's issue of the journal Nature.
Understanding a "Killer"
The genome data sheds light on the process of Africanization by suggesting that Apis mellifera originated in Africa, then spread to Europe and Asia in two separate migrations. (Related: photo: "Oldest-Ever Bee Found in Amber" [October 25, 2006].)
The infamous African "killer" bees, a subspecies of honeybee known as Apis mellifera scutellata, were introduced to Brazil in 1956. The aggressive insects have almost replaced the so-called European honeybees that were present in the region and have penetrated as far as Argentina to the south and California to the north.
The new study also reveals how elements in the genome may influence the development of vastly different honeybee castes, such as queens and workers, from the same genetic material.
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