In the first global analysis of genetic variations in honeybees, researchers from Uppsala University in Sweden have discovered the crucial pollinators likely originated from Asia, not Africa, as previously thought.

Representing an important component of the global food cycle -- since one third of human food sources are dependent on the pollination of fruits, nuts and vegetables -- the honeybee, also called Apis mellifera in scientific circles, has shown a wide range of diversity across the planet, an apparent result of the insect's great ability to adapt to various environments.

Of course, notes the findings of a new paper published in the journal Nature Genetics, massive losses of honeybee colonies in recent years have caused considerable concern.

So, as the bees are threatened by disease, climate change and population management practices, before they can find ways to help the flying critters survive, it's vital researchers understand the evolutionary history of honeybees and how they are adapted to different environments across the world.

"We have used state-of-the-art high-throughput genomics to address these questions, and have identified high levels of genetic diversity in honeybees. In contrast to other domestic species, management of honeybees seems to have increased levels of genetic variation by mixing bees from different parts of the world," Matthew Webster, a researcher at Uppsala's department of Medical Biochemistry and Microbiology, said in a news release. "The findings may also indicate that high levels of inbreeding are not a major cause of global colony losses."

Another unexpected find was that the honeybees seem to have originated from an ancient line of cavity-nesting bees migrated from Asia around 300,000 years ago and subsequently spread quickly across Europe and Africa.

"The evolutionary tree we constructed from genome sequences does not support an origin in Africa," Webster said. "This gives us new insight into how honeybees spread and became adapted to habitats across the world."

The patterns of genome variation among the honeybees hold signs of large cyclical fluctuations in population size, which took cues from the patterns of glaciation over the millennia.

That is a direct indication that climate change had significantly affected honeybee populations through time.

"Populations in Europe appear to have contracted during ice ages, whereas African populations have expanded at those times, suggesting that environmental conditions there were more favorable", he explained.

The study, he asserted, "provides new insights into evolution and genetic adaptation and establishes a framework for investigating the biological mechanisms behind disease resistance and adaptation to climate, knowledge that could be vital for protecting honeybees in a rapidly changing world."