A bee's life

Blog post

Can the humble honeybee teach us how to live longer? 

The world's most devoted pollinators, the common honeybees, spend their daylight hours feeding on flowers, brushing against pollen, and spreading it wherever they go. The estimated 1.7 trillion honeybees buzzing around the planet give us food, honey, beeswax and medicine.

If that wasn't enough, now honeybees are showing scientists how to live longer. Nicolas Martin at the University of Wollongong has been conducting research into the lifespans of honeybees, and it seems this humble insect could hold the secret to better understanding ageing and potentially to helping humans increase their lifespan.

"Female honeybees can be workers or queens. They are genetically identical but while workers live for weeks, queens can live for years," says the young PhD candidate, who has embraced the world of apiary - or beekeeping - since he began studying the black-and-gold creatures.

Because of this extraordinary difference in lifespan between workers and queens, Nicolas, working with Professor Paul Else at UOW's Faculty of Science, Medicine and Health, began studying honeybees more closely.

"I was curious about ageing but not convinced by the way traditional medical research looked at the ageing process. Studying ageing while working with honeybees turns out the best comprise for me and I found I really like working with the bees."

Findings from Nicolas's research have linked the difference in lifespan between the queen bee and workers bees to a difference in nutrition. "The bees already did the work for us, by evolving a system in which the same egg has a plasticity of lifespan that outrivals any experimental lifespan extension by many folds."

At the larvae stage, both the worker and queen bees are fed the same food: royal jelly. The milky liquid, which is also called bee milk, is a mixture of proteins and sugars that is secreted from special glands in the heads of workers bees.

Royal jelly's powerful properties have fascinated civilisations for thousands of years, going back to the time of the ancient Egyptians. However, when the bees emerge from their honeycomb cells and begin their adult life, the type of food changes between castes. The worker bees feed on honey and pollen while the queen is fed only royal jelly, mouth-to-mouth by worker bees.

It seems you really are what you eat - if you're a bee. Pollen and royal jelly have very different fat compositions. Pollen has a lot of polyunsaturated fats while royal jelly has virtually none.

This difference in food consumption leads to a difference in lipid membrane fats between the castes. The researchers theorise that this difference may be the underlying reason why queen bees live 100 times longer than ordinary worker bees.

"Extend the lifespan of an animal and you delay the onset of ageing-related diseases. That is why honeybees, or any other social insect, are an excellent model to study ageing." - Nicolas Martin

So far, Nicolas has found that in a natural hive, the new worker bees have a similar membrane fatty acid composition to the queen but within the first week of adult life, they increase the polyunsaturated content and decrease the monounsaturated content of their membranes, and his results have linked this change to the consumption of pollen by workers

"Extend the lifespan of an animal and you delay the onset of ageing-related diseases. That is why honeybees, or any other social insect, are an excellent model to study ageing. Now, we are looking at extending the lifespan of worker bees," Nicolas says.

Nicolas's research involves feeding emergent captive worker bees with a diet that differs only in its polyunsaturated fat content. This diet could lead the worker bees to maintain a queen-like lipid membrane composition, and if his hypothesis is right, they should live for longer compared to worker bees on the usual diet of honey and pollen.

"The ability to extend bees' lifespans by nutritional manipulation will provide an important experimental tool to investigate the process of ageing and could unlock secrets to better understand ageing and help humans to age well.

"Bees have a lot to teach us and what we learn from them may someday help slow down the ageing process and troubleshoot some very real human problems," Nicolas says.

The bee's universe is a tough monarchy. All worker bees are females while the very few male bees known as drones live for the primary purpose of mating with the queen. Those drones that do get the chance to mate are in for a sobering surprise: they die after mating.

Nicolas has nine colonies ranging from a few thousand to 150,000 bees per colony under his care. "I've been stung too many times to remember," he says. "Hey, it's not always easy working with over one million females that have stingers."

Since working with bees Nicolas has become quite fond of his work subjects. He points out that honeybees are essential for our ecology and economy; kill the bees and there is a lot less pollination.

These under-appreciated workers pollinate 80 per cent of flowering crops around the world, which equals one-third of everything we eat, and their service to the food industry is counted in billions of dollars per year.

Unfortunately for bees, it's not all good news. Colony collapse disorder has wiped out millions of honeybee colonies around the world. The disorder is still not fully understood, but a combination of parasites, viruses, poor nutrition and pesticides are thought to be behind the widespread deaths.

Then there is the Varroa destructor mite. These parasitic mites require honeybees to host, survive and reproduce. One of the serious problems caused by Varroa is the transmission of viruses to the honeybees causing deadly diseases. Australia is one of the last remaining regions in the world that has been spared from this hive killer. But it is closer to coming here than ever, having spread to New Zealand and Indonesia in 2006.

Nicolas thinks bees are easily one of the most important insects to humans. "These buzzing girls deserve a huge thanks. Not only are they helping us understand the ageing process, they help in providing our fruits, vegetables and beautiful flowers."

Here's to the humble honeybee.