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Alison McAfee | Honey Bee Hub

Breeding a better bee: Three social immunity traits, one massive experiment

Photo: Amanda Goodman-Lee
Sick honey bee colonies can be treated with antibiotics and miticides, but pathogens are evolving resistance to fight back. Now, researchers have developed a new counter-attack.

Continue reading “Breeding a better bee: Three social immunity traits, one massive experiment”

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Hives for Humanity: Using bees for social empowerment in Vancouver’s Downtown Eastside

Photo: Sarah Common
A Canadian mother-daughter team is bringing life and colour to the Hastings homeless community by installing therapeutic apiaries and gardens. Continue reading “Hives for Humanity: Using bees for social empowerment in Vancouver’s Downtown Eastside”
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Long live the sperm

Honey bee queens keep drones’ sperm alive inside them for years, but some surprising environmental triggers can cause massive sperm death.

“Give the drone’s thorax a pinch,” Jeff Pettis instructed as I took the drone he handed me. “Then squeeze the abdomen between your thumb and forefinger, rolling from the front of the abdomen to the tip.” I flipped the drone upside down and started to pinch the thorax as coached, feeling a crispy crunch as it buckled and killed the bee. I stifled a shudder – I always hate the sensation of crushing an exoskeleton, whether it belongs to a bee or another insect. The drone’s abdomen still pulsed with reflexive breaths, which quickly stopped as I squeezed it from front to back.

Jeff was showing me how to harvest fresh semen from drones. That day, we were just practicing, but semen collected in this way can then be used for instrumental insemination or tested for sperm viability. And sperm viability is a critical determinant of queen quality, and ultimately, colony longevity—dud sperm directly translate into fewer workers, less genetic diversity, and potentially smaller colonies. New research suggests that sperm viability is compromised by common challenges like temperature stress and pesticide exposure, even more than previously thought.

As I squeezed the abdomen, it felt like it was going to explode between my fingers. But sure enough, instead of bursting, the endophallus shot out from the hind end, pausing with two bright orange horns (cornuae) poking out as if someone was blowing into an inside-out rubber glove. It looked truly alien. “That’s a partial eversion,” Jeff confirmed. “Now keep squeezing.”

Figure 1
Drones have elaborately structured penises. A) A drone awaiting penile eversion. B) Partial eversion, with the corunuae clearly visible (Y-shaped horns). They are thought to act like hooks, helping to grip the queen during mating. C) Full eversion, displaying the whole endophallus. Photos by Alison McAfee

The rest of the phallus exploded from the abdomen with a pop. Sitting on top of the bulbous end were a few microlitres of creamy café au lait colored semen, poised for collection.

A drone’s purpose in life is to grow big enough and strong enough to compete with other drones for access to a virgin queen during her nuptial flight. If successful, they mate in mid-air, he deposits that drop of semen inside of her (explosive pop included), his phallus rips from his body, and he falls to his death. For every queen, about fifteen to twenty drones mate with her and reach this morbid fate. But while the drones themselves may die, their sperm will live inside the queen for years, fathering millions of offspring over the course of the queen’s life.

How is it possible for sperm to stay alive in the queen for so long, when in other animals, they live only minutes or days? Human sperm, for example, only stays alive outside a male’s body for about twenty minutes (or several days, in the female’s fallopian tube). Queen ants, which are also social insects, put even honey bees to shame; most ant queens store live sperm for upwards of ten years.

In a social insect’s kingdom, the dogma is not only long live the queen, but also long live the queen’s sperm. Researchers have been searching for the mechanism of these remarkable feats of sperm storage since the 1960s, when Eugenia Alumot, from Rehovot, Israel, began investigating the sugars and enzymes that could be providing honey bee sperm with energy inside the queen’s spermatheca (the specialized organ that stores the sperm).

Now, we know that after a burst of energy used to out-swim other sperm and gain access to the spermatheca, the sperm fall into a fairly quiescent life. Specific metabolic pathways are dialed back, so once inside the spermatheca, the sperm metabolize nutrients differently. This probably enables them to minimize damage – and cell death – caused by molecules called “reactive oxygen species,” which are by-products of some types of energy-generating metabolism. But these carefully tuned metabolic shifts can easily be thrown off-balance.

Continue reading the full article in the August 2018 issue of American Bee Journal.

The blueberries and the bees

Photo: Marta Guarna
Thousands of honey bee colonies arrive in the Fraser Valley’s blueberry fields every spring, but beekeepers are worried this crop may be harming their bees. Continue reading “The blueberries and the bees”

Who’s got the guts?

Image: Waldan Kwong
The honey bee gut is more than just a food processing chamber. It’s also home to hundreds of millions of microbes – some of which help the host, and some of which destroy it.

Continue reading “Who’s got the guts?”

Hygienic behavior and the scent of death

Photo: Alison McAfee
HYGIENIC WORKER BEES have a demanding job. They are key players in the hive’s social immune system, removing sick and dying brood before the diseases they harbor can spread.  Continue reading “Hygienic behavior and the scent of death”

How a Nobel Prize in physiology created tomorrow’s Varroa control

Photo: Alison McAfee
Every beekeeper has wrestled with the Varroa destructor mite. Every beekeeper also knows we’re running out of weapons.  Continue reading “How a Nobel Prize in physiology created tomorrow’s Varroa control”

Hive of science for bees: Report from an international pollinator workshop

Photo: Emilie Egea
If you had the power to give $300,000 in annual research grants, how would you choose what to fund? The Rovaltain Foundation – in Alixan, France – decided to host researchers from all over the world to discuss the most important issues surrounding bee health. Continue reading “Hive of science for bees: Report from an international pollinator workshop”

Transgenic honey bees: Should they take wing in the field, or stay in the lab?

Love it or hate it, in this INK article I argue that genetic engineering is not inherently evil. Whether it’s good or bad is dictated by the context, motive, and intent – not the technology.

Full texts now available

Hello everyone! I just wanted to write a quick note saying that all articles that have appeared in American Bee Journal have been updated to contain the article text & figures instead of short excerpts. The article on Hives for Humanity will be appearing in the October issue, at which time I’ll make that full text available too. Enjoy!

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