Bees Without Mothers More Prone To Disease: Study

Mom’s the word for bees as they help stave off disease, according to a new study.

Researchers found that family-orientated bees lacking a mother figure are more susceptible to disease and parasites during the early stages of their development.

Canadian scientists observing a tiny species of carpenter bee – which fastidiously cares for and raises its young – found huge benefits to young members of the hive which received maternal support.

The researchers observed bees throughout all stages of development and found that a lack of a motherly figure left bees – which are often viewed as very solitary creatures – more susceptible to harmful parasites, fungi, bacteria and viruses.

And they even found that motherless bees behaved differently to those with influential maternal figures.

The study, published in the journal Communications Biology, shows how “vital” a maternal figure is in the development of young bees – much the same as they can be with humans.

The Canadian researchers, from York University in Toronto, looked at four developmental stages in the early lives of these carpenter bees (Ceratina calcarata), starting from the larvae stage.

They then compared the development of the bees that had maternal care with those that did not.

The team found that, not unlike the effect a caring mother can have on their human child, maternal care in the carpenter bees helped to stave off an overabundance of harmful diseases during early development.

Without any maternal care, however, the researchers found the pathogen load of the developing bees ballooned, mostly with fungi, which can detrimentally impact the bees’ microbiome – a critical component in bee health – as well as their development, immune system and gene expression.

The scientists further found that this could lead to changes in brain and eye development – and even in the behavior of the young bees.

The developmental changes, sparked by which genes were expressed or suppressed, upregulated or downregulated, along with disease loads, depending on the presence or lack of maternal care, created knock-on effects on the microbiome and bee health.

The biggest fungus to affect the bees was Aspergillus – known to induce stonebrood disease in honey bees which ‘mummifies’ offspring.

In later developmental stages, the lack of care can lead to a reduced microbiome, increased susceptibility to diseases and poor overall health.

Senior author Sandra Rehan, an evolutionary biologist and a professor in York’s Faculty of Science, explained: “There are fitness effects resulting from these fungal infections.

“We are documenting the shifts in development, the shifts in disease loads, and it is a big deal because in wild bees there is a lot less known about their disease loads.

“We are highlighting all of these factors for the first time.”

Lead author Dr. Katherine Chau added: “We found really striking shifts in the earliest stages, which was surprising as we did not expect that stage to be the most significantly changed.

“Looking at gene expression of these bees you can see how the slightest disregulation early in development cascades through their whole formation.

“It is all interconnected and shows how vital maternal care is in early childhood development.”

Rehan argued that if people better understand the complexities of bees they might be more inclined to care about their diversity.

“Often people see bees as a monolith,” she said.

“But when you understand the complexity of bees and that there are wild bees and managed bees, people are more likely to care about bee diversity.

“It is a complex paper that provides layers of data and shows the power of genomics as a tool.

“It allows us to document the interactions between host and environment. I think that is the power of this approach and the new technologies and techniques that we are developing.”

Produced in association with SWNS Talker