The first global analysis of genome variation in honeybees has been presented by researchers from Uppsala Univ as per study published in Nature Genetics. High level of genetic diversity in boneybees was surprisingly shows in findings and also indicatge that the species are not from Africa as previously thought but originated from Asia.
Crucial importance for humanity are the honeybees (Apis mellifera). Pollitionation of fruits, nuts and vegetables by honeybees and other insects are dependable to the extent of one third of our food. The major cause of concern in the recent years are the extensive losses of honeybee colonies. Disease, climate change and management practices are the main threats to honeybees. It is important to understand evolutionary history of honeybees and how they are adapted to different environments across the world to combat these threats.
“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. The findings may also indicate that high levels of inbreeding are not a major cause of global colony losses,” said Matthew Webster, researcher at the department of Medical Biochemistry and Microbiology, Uppsala Univ.
Honeybees seem to be derived from an ancient lineage of cavity-nesting bees that arrived from Asia around 300,000 years ago and rapidly spread across Europe and Africa is an unexpected result. Research suggesting honeybees originate from Africa stands in contrast to the previous research.
“The evolutionary tree we constructed from genome sequences does not support an origin in Africa, this gives us new insight into how honeybees spread and became adapted to habitats across the world,” said Matthew Webster.
Large cyclical fluctuations in population size that mirror historical patterns of glaciation is an indication of the hidden in the patterns of genome variation and a signal to it. Thus climate change has strongly impacted honeybee populations historically is indicated.
“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,” said Webster.
The researchers also identified specific mutations in genes important in adaptation to factors such as climate and pathogens, including those involved in morphology, behavior and innate immunity.