Biodiversity protects bee communities from disease

A new analysis of thousands of native and non-native Michigan bees shows that the most diverse bee communities have the lowest levels of three common viral pathogens.

A European honey bee extracts nectar from an aster flower. Photo: John Severns

University of Michigan researchers netted and trapped more than 4,000 bees in 60 species. The bees were collected at winter squash farms across Michigan, where managed honeybee colonies and wild native bees pollinate the squash flowers.

All but one species -- Apis mellifera, the common European honeybee -- are native bees. The number of bee species found at each farm ranged from seven to 49.

Consistently, lower virus levels were strongly linked to greater species richness among the local bee communities. The study was published in the journal Ecology.

"This result is exciting because it suggests that promoting diverse bee communities may be a win-win strategy to simultaneously reduce viral infections in managed honeybee colonies while helping to maintain native bee biodiversity," said study lead author Michelle Fearon.

"In light of recent global pollinator population declines that are due in part to the spread of pathogens, these results offer hope that conservation efforts could also broadly benefit pollinator health," said Fearon. She is now pursuing a follow-up study that explores how natural areas keep pollinator communities healthy.

The study is the first to show that high levels of biodiversity in bee communities can help dilute the harmful effects of viral pathogens. Support for this "dilution effect" has been reported in other host-pathogen systems, such as tick-borne Lyme disease, but this is the first time it's been seen with pollinator viruses.

Fearon and her colleagues collected 4,349 bees at 14 Michigan winter squash farms over two summers. Michigan winter squashes include acorn squash, butternut squash, spaghetti squash and pumpkins.

Four types of bees -- the European honeybee, the eastern bumblebee (Bombus impatiens), the squash bee (Eucera pruinose) and several species of sweat bee (genus Lasioglossum) -- were the most consistently abundant species among the bee communities sampled. (National Science Foundation)

YOU MAY ALSO LIKE

How did dogs get to the Americas?

The history of dogs has been intertwined, since ancient times, with that of the humans who domesticated them. But how far back does that history go in the Americas and which route did dogs use to enter that part of the world?

Study highlights ‘unbridled globetrotting’ of the strangles pathogen in horses

In the largest ever study of its kind into an equine pathogen, scientists in 18 countries used the latest DNA sequencing techniques to track the bacteria (...)

Universe Might Be One Big Neural Network

In a thought-provoking new paper, a physicist suggests the whole universe could be a single neural network—a competing “theory of everything” that could unite quantum and classical mechanics, he says.

World's oldest DNA reveals how ice age mammoths evolved

Discovery of new lineage, insights into when and how fast mammoths adapted to cold climate.

Through the looking glass: artificial ‘molecules’ open door to ultrafast devices

Researchers from the University of Cambridge and Skoltech in Russia have shown that polaritons, the quirky (...)

Sea ice kept oxygen from reaching deep ocean during last ice age

Sea ice is like a closed window for the ocean.