Honeybees originated in Asia, and not Africa, according to a new genetic analysis of the species.
This global analysis of genome variation was the first of its kind ever done on the tiny flying creatures. The study revealed previously-unknown information about the genetic history of honeybees. One of the findings made by researchers was that honeybees enjoy a great deal of genetic diversity.
"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. The findings may also indicate that high levels of inbreeding are not a major cause of global colony losses," Matthew Webster, from the department of Medical Biochemistry and Microbiology at Uppsala University, said.
The lineage of honeybees was traced back by Webster and his team, who found the insects originated from a type of cavity-nesting bee in Asia 300,000 years ago. The bees spread quickly throughout Europe and the Africa. This is contrary to previous research, suggesting an African origin.
Honeybees and other insects pollinate roughly one-third of crops consumed by humans. They have experienced widespread population losses, as hives lose a greater-than-normal number of bees each winter, and are unable to recover during warmer months. This has been termed Colony Collapse Disorder, or CCD.
Genetic sequencing of honeybees reveals the large changes in population sizes were timed with changes in global temperatures. This indicates the insects are highly-susceptible to climate change.
"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," Webster stated in a university press release.
Apiologists also studied genetic mutations in the insects, to see how the animals evolved defenses against pathogens and changing climates. These evolutionary adaptations involved changes in basic body structure, as well as behavior of the insects.
Study of the genetic makeup and history of honeybees could assist researchers in understanding and combating CCD. The ultimate cause of the widespread death is still unknown, although climate change, varroa mite, and pesticides are considered. Population losses were first reported in 2006. Similar losses were reported in the 1880's, 1920's, and 1960's, although it is uncertain if the causes of those deaths were the same as today.
"In 1903, in the Cache Valley in Utah, 2000 colonies were lost to an unknown 'disappearing disease' after a 'hard winter and a cold spring.' More recently, in 1995-96, Pennsylvania beekeepers lost 53 percent of their colonies without a specific identifiable cause," US Department of Agriculture (USDA) officials wrote on their website.
Genetic analysis of honeybees, and what the data can tell us about the evolutionary history of the insects was profiled in the online journal Nature Genetics.
