Western honey bees likely originated in ASIA — and not in Africa as previously thought, study reveals
- Researchers from Canada’s York University sequenced 251 honey bee genomes
- Analysis indicated that the pollinating insect likely originated in Western Asia
- From here it spread to Africa and Europe and formed seven different lineages
- The bees appear have a core set of genes that let them to adapt to new settings
The origins of the western honey bee — Apis mellifera — likely lay in Asia, not Africa as was previously thought, a study has concluded.
Researchers from Canada’s York University settled this long-debated little mystery by sequencing the genomes of 251 honey bees from across the insect’s native range.
The western honey bee — used for crop pollination and honey production across most of the globe — has a remarkable ability to survive in different environments.
It can live in tropical rainforests, arid climes and even temperature regions with cold winters, and is native to to Asia, Africa and Europe.
After originating in Western Asia, the team believed that it split into seven different lineages and expanded independently into both Africa and Europe.
The origins of the western honey bee — Apis mellifera — likely lay in Asia, not Africa as was previously thought, a study has concluded. Pictured: a honey bee on a rudbeckia flower
The investigation was undertaken by biologist Amro Zayed of Toronto’s York University and his colleagues.
‘As one of the world’s most important pollinators, it’s essential to know the origin of the western honey bee,’ Professor Zayed said.
Only then, he explained, can we ‘understand its evolution, genetics and how it adapted as it spread.’
In their study, the researchers sequenced and analysed 251 western honey bee genomes — representing a total of 18 of the 27 different subspecies.
They used this data to reconstruct the most likely pattern of dispersal for the different honey bee lineages — and their collective point of origin.
The team found that an origin in Western Asia, rather than one in Africa, was the most strongly supported by their genetic data.
After originating in Western Asia, the team believed that the western honey bee split into seven different lineages (pictured) and expanded independently into both Africa and Europe
In their study, the researchers sequenced and analysed 251 western honey bee genomes — representing a total of 18 of the 27 different subspecies. They used this data to reconstruct the most likely pattern of dispersal for the different honey bee lineages. Pictured: two different possible biogeographic range reconstructions, as calculated using so-called single nucleotide polymorphisms across the whole genome (left) and just in protein-coding regions (right)
The researchers also found that the honey bee genome has a number of ‘hot spots’ that allowed the insects to adapt to new niches and geographic areas.
In fact, of the more than 12,000 genes in the bee genome, only 145 had repeated signatures of adaptation associated with the formation of the major honey bee lineages seen today.
‘Our research suggests that a core-set of genes allowed the honey bee to adapt to a diverse set of environmental conditions across its native range by regulating worker and colony behaviour,’ said paper author and biologist Kathleen Dogantzis.
The sequencing efforts also led to the discovery of two new and distinct western honey bee lineages — one from Egypt and the other from Madagascar — bringing the total to seven.
The researchers said that they hope that their study will finally lay to rest the debate as to where the western honey bee originally came from — freeing up future research to explore further how the insects adapted to different climates
The researchers said that they hope that their study will finally lay to rest the debate as to where the western honey bee originally came from — freeing up future research to explore further how the insects adapted to different climates.
‘It’s important to understand how locally adapted subspecies and colony-level selection on worker bees contributes to the fitness and diversity of managed colonies,’ explained Ms Dogantzis.
The full findings of the study were published in the journal Science Advances.
DECLINING BEE POPULATIONS
Declines in recent months to honey bee numbers and health caused global concern due to the insects’ critical role as a major pollinator.
Bee health has been closely watched in recent years as nutritional sources available to honey bees have declined and contamination from pesticides has increased.
In animal model studies, the researchers found that combined exposure to pesticide and poor nutrition decreased bee health.
Bees use sugar to fuel flights and work inside the nest, but pesticides decrease their hemolymph (‘bee blood’) sugar levels and therefore cut their energy stores.
When pesticides are combined with limited food supplies, bees lack the energy to function, causing survival rates to plummet.