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"Honeybees are the one species we can manipulate, and manage, and transport, package and deliver in a timely manner," says May Berenbaum. "They are exceptionally well suited to industrial agriculture."
Though pollination depends upon an individual bee flitting from plant to plant, leaving a fertilizing trail of pollen as it gathers nectar, a single honeybee in and of itself is not a viable organism. Rather, it is the hive that is the true animal, functioning according to its own biological necessity.
Just as a dog will shed its coat in summer, when a hive becomes overcrowded it will produce more queens. Nourished by the hive with royal jelly, the so-called swarm queen emerges from her queen cell and forces the incumbent queen whom the hive has denied food so she'll be light enough to fly to flee and start another hive with a contingent of field bees that follow her.
Once in possession of the hive and often after killing rival swarm queens the presumptive queen embarks on her maiden flight. High above the trees, the virgin queen mates with up to twenty drones. Their biological function complete, the drones fall away and die. The new queen then returns to the hive and begins laying eggs. Unless she is later usurped by another swarm queen, this is the only time she'll ever fly.
It is this predictable process that allows beekeepers like Bergman to "split" hives by taking half of the bees from a hive that is preparing to produce a swarm queen and placing them, via the hive box's removable honeycomb trays, into a new hive. The beekeeper then introduces a queen to the new hive, which in a few weeks will again grow to capacity effectively doubling the beekeeper's honeybee population.
"There's no other pollinator that we have such a handle on," says Berenbaum. "Bees have this social structure, and behaviors that go along with that social structure. With contemporary U.S. monoculture agriculture, we have vast expanses of crops that simultaneously need pollination services over a very short amount of time. There are not many insects that have the population capacity to meet that kind of demand. [In a single hive] there are 30,000 to 40,000 foragers at any given time."
Not only have honeybees been able to meet the population demand of an agricultural system based on vast tracts of the same crop blooming at the same time, they are also attractive because of their sheer versatility. Unlike, say, butterflies, which primarily pollinate wildflowers and only a few cash crops, honeybees can handle hundreds of different flower species.
The very versatility that makes the honeybee so attractive to modern agriculture has made it a highly managed species, susceptible to a host of genetic problems.
"[Before varroa mites] we had this background of feral bees. Queens would fly off and mate with whatever drones they found," explains the U of I's Charlie Whitfield. "In a colony you'd have a fair amount of diversity; all the workers would have the same mother, but they'd have genetically diverse fathers. With artificial insemination, they'll still have multiple fathers, but you're getting drones that are in your own apiary."
The lack of genetic variation isn't a problem, so long as a hive remains healthy. But when an unknown pathogen attacks, the hive may well lack the necessary genetic variants to adapt to the new threat. Often that means death for the entire hive.
What's more, while the social structure of the hive may be efficient at protecting young bees from outside toxins and pests, honeybees have roughly half as many detoxification genes as other insects, which might render them more susceptible to, say, manmade insecticides. But scientists don't know whether this is the case, nor whether the paucity of genes is a function of human intervention or natural evolution.
"They're not utterly incapable of processing pesticides otherwise we couldn't use them," Berenbaum notes. "But we have this confounding problem, in that people care about dead [honey]bees. They notice them. If there's an accidental insecticide drift that wipes out a population of carpenter bees, who's going to notice? Who's going to care? There's this problem of beekeepers pointing out every mass killing of honeybees so the perception is that they must be very susceptible to pesticides. But in reality we don't have an abundance of data."
Once he has extracted a bee's innards, Reed Johnson moves quickly through the crowded biology lab and places the digestive tract back into the deep freezer.
Like the rest of the CCD working group, Johnson is studying frozen bee samples that predate CCD, along with specimens culled from collapsed hives. One of CCD's primary characteristics is that adult bees leave the hive and do not return a knotty issue for researchers who are left with few options but to study the survivors.
"You can't do a lot of the genetic analyses on dead bees, because the part we're interested in degrades immediately," Johnson says. "You have to have live bees that were frozen on dry ice. So they're hard to get."
Once Johnson has collected enough gut samples, he places them into a test tube and pulverizes them with an electric pestle, then uses a centrifuge to extract the RNA from the mash. Like the rest of the CCD working group, Johnson is a beneficiary of geneticists who last year published the honeybee genome all 11,000 genes of it.