A bumble bee with a RFID tag attached to its back. The RFID tag allows scientists to keep track of their foraging activity and how well they are supporting their colony. Photo / Brian Cutting
A bumble bee with a RFID tag attached to its back. The RFID tag allows scientists to keep track of their foraging activity and how well they are supporting their colony. Photo / Brian Cutting
When it comes to factors that can hinder your survival, you'd expect being a quick study wouldn't be on the list.
Yet that's just the conundrum facing our humble bumblebee – and one that Kiwi scientists are just starting to grapple with.
In a study published last year, Plant and Food Research scientist Dr Lisa Evans and colleagues surprisingly demonstrated how bumblebees that learn faster had a much shorter foraging lifespan than their slow-learning co-workers.
They also found that the fast-learning bumblebees collected food at rates comparable to mates in the colony that were less smart, and completed a similar number of foraging bouts per day.
In a new project that just received a $300,000 Marsden Fund grant, Evans and her team will compare how wild bumblebees learn differently in certain kinds of floral environments.
They will test the advantage of being a good learner by transplanting colonies of bees from each of the two environments into the other - and then measuring any changes in their reproductive success.
This could reveal whether learning potential provides a special advantage to bumblebee colonies in some environments, but not others.
"The over-arching question I am addressing is: when is it beneficial for individuals and populations to be good learners, or more specifically learn quickly?" Evans explained.
"We know that learning has advantages - it can enhance the ability of an animal to efficiently find food, choose mates, and avoid predators.
"We also know that being a 'fast learner' is costly to the individual, because cognitive function has a 'metabolic cost' in the form of energetically expensive neural tissue."
But that didn't explain when it made sense to pay this cost.
Bumblebees were ideal candidates for investigating links between environment, learning capacity and reproductive success because they could solve a wide variety of problems, and seemed to have many cognitive abilities akin to mammals.
Plant and Food Research scientist Dr Lisa Evans is leading a new study into bumblebees. Photo / Brian Cutting
Further, they were "generalist foragers" - and as such had to learn the certain traits of flowers that told them the quality and quantity of reward they'd receive in return for their hard work.
It was just these reward cues, based on the scent and colour of flowers, that Evans and her team would assess at a mix of sites around the country.
"We will then determine whether learning potential provides selective advantage to bumble bee colonies in complex floral environments, by carrying out a reciprocal transplant experiment, introducing colonies from each of the two environments into the other and comparing their foraging and reproductive success."
Next, the team would use DNA technology to pick apart genetic and epigenetic factors at play in their learning.
Evans said the study stood to yield important new insights which could ultimately show how different environments could affect whether a colony would be successful.
"In an applied sense, this knowledge could feed into habitat and bumble bee conservation programmes overseas, and be used to support populations of these important pollinators in New Zealand."
Bumblebees make great pollinators as they perform "buzz pollination", an effective technique used to free pollen from anthers, and can forage in poor weather conditions that keep honeybees indoors.
Further, their large size and hairy bodies mean they can collect larger quantities of pollen - it's estimated a single bumblebee can do the work of 50 honey bees - and they visit a wider diversity of flowers, increasing pollination.
Plant and Food Research pollination scientists have been using them in trials to investigate whether they could play a larger role in orchards around the country.
Evans will collaborate on the new study with Dr Jenny Jandt of Otago University, Dr Felicity Muth of the University of Nevada in the US and Professor Nigel Raine of the University of Guelph in Canada.
