BUMBLEBEES don't get the respect they deserve. If you're like most people, you think of them as cute and fuzzy. One researcher calls them the pandas of the insect world. Maybe you've heard that physics says they shouldn't be able to fly. (Not true, by the way.)

This column isn't really about bumblebees—at least, it's not just about bumblebees. It's about unintended consequences, complex systems, the endangered species act, and bumblebees. Of course, it's also about science fiction, because an awful lot of science fiction deals with unintended consequences. A character invents something that they think will improve the world. But if the invention actually did improve the world and everyone lived happily ever after, it would be a really dull story. To get a good story, something must go terribly—and unexpectedly—wrong. Consider Ursula K. Le Guin's novel, Lathe of Heaven, which tells the story of a man whose dreams alter reality. He tries to dream a better world—and every attempt makes his situation worse. Or think about "The Monkey's Paw," a 1902 story by W. W. Jacobs, about a magical object that grants its owner three wishes. Unfortunately, each wish comes at a price—and the price gets more horrible with each wish. Or, perhaps most appropriate to the time in which we find ourselves, remember Ray Bradbury's famous short story, "A Sound of Thunder." In it, a time traveler accidentally steps on a butterfly in the distant past—and returns to a dramatically changed future in which a power-mad dictator has been elected president. And that brings us back to insects. We'll get to unintended consequences and complex systems in a bit. But first, let us tell you a thing or two about bees.

You've probably heard that honeybees are in trouble. Back in the 1980s, honeybee hives in the U.S. were invaded by the Varroa bee mite, a blood-sucking parasite that weakens bees and, left unchecked, can kill colonies. Then in 2006, beekeepers noticed that more hives were failing to survive the winter. They'd find colonies that had "collapsed"—the worker bees were gone, leaving the queen alone.

Everyone started worrying about honeybees. That's all very well, and indeed you should worry about honeybees. But you should also know that worrying about honeybees is a little like worrying about cows or pigs or any other domesticated animal. The honeybees that live in hive boxes and buzz around the almond orchards in California's central valley or Washington State's apple orchards are European honeybees, descendants of a long line of domesticated bees. Ancient Egyptian tomb paintings show beekeeping; the Minoan Civilization kept bees and traded honey. Over thousands of years, the characteristics of honeybees gradually changed, influenced by human selection to produce bees with maximum honey production and storage, easily pacified by smoke, and less likely to sting.

Many of the honeybees' problems are related to human activity. That blood-sucking Varroa bee mite? It was discovered in 1904, a parasite of the Asian honeybee. The mite invaded human-managed European honeybee hives in Asia and hitched a ride with the hives to Africa, then to Europe, and in 1987, to the U.S. (Mexico and Canada closed their borders to traveling bee hives to keep the mites out.) A host of other factors may be involved in the honeybees' problems, including agricultural pesticides and other chemicals, along with microbial pathogens and parasites.

Why are people right to worry about honeybees? Because these little domestic animals are the ultimate sex workers. They buzz from flower to flower, transporting pollen from one flower to the next. It's an important job, as anyone who likes to eat should recognize.

By transporting pollen, bees makes it possible for flowers to become fruit. Without bees to pollinate them, there are a lot of food crops we won't be growing—tree fruits like apples and peaches and pears, melons of all sorts, berries, and squashes. Estimates vary, but the USDA says that about a third of human foods and beverages depend on bee pollination.

Pollinators have spent the last hundred million years or so evolving along with flowering plants that make the seeds and fruits we eat. Start killing off the pollinators, and we're all in trouble.

We've got nothing against honeybees—we're very fond of them, their honey, and the fruits they pollinate. But they are way late to the Pollinator Extinction party.

Let's talk about the bees that get no respect. Across North America and Europe, bumblebee populations are in decline. Some bumblebee species have disappeared in parts of their range—the bees have gone locally extinct. In one study, scientists compared historic data with current observations and found that half of the species of bees native to the American Midwest are now extinct in parts of their range.

That's a problem because those native bees were...well...busy. The same researchers who noted the decline in Midwestern native bees also noted that wild native bees were better at pollinating crops than honeybees—native bees were twice as good as honeybees, they estimated.

Why are native bees having so much trouble? The answer, as Paul likes to say, is complicated. These bees share many of the problems that the honeybees face—and have a few more that are all their own.

Commonly used agricultural pesticides are thought to be part of the problem. Loss of habitat is another part. Urban settings have fewer food sources—fewer flowers and more flowers that people have selected for looks, not their nectar production. Even in agricultural areas, bees may not find the food they need year-round, since crop plants tend to flower all at once.

As changes in land use and climate have altered the available plants in any given area, the native bees adapt, shifting to available plants. You might think that would be good, but not necessarily.

When there are plenty of flowers to go around, different species of bees are less likely to share the same flowers. But when flowers are scarce, multiple bees may visit the same flower. That's a bit like drinking from the same water glass. Parasites and diseases can pass from one species to another. Studies have shown that two honeybee diseases have crossed over into wild bumblebee populations.

Oh, yeah—climate change is also affecting the bees' range. Drought and flood, shifting temperatures—these affect the plants, which in turn affects the bees.

The decline of bee populations means that these populations are less able to adapt to change in a time of change. Think about natural selection and how it works. You have a population of animals—let's say bumblebees. They're all bumblebees and they are good at the sorts of things bumblebees are good at.

As any kindergartener can tell you, bumblebees are fuzzy. With their fuzzy insulation, bumblebees can fly and forage at colder temperatures than European honeybees. That's why you'll see bumblebees out and about at temperatures that keep honeybees in their hives. Paul reports seeing a bumblebee covered in frost, clinging to a plant and waiting for the sunlight to hit it. Bumblebees count on the sunshine to warm them up. They also use a special trick: They vibrate their flight muscles to raise their body temperature until they're warm enough to fly.

But wait, there's more: Scientists recently discovered that bumblebees can learn new behaviors from each other. In London, a group of researchers studying insect cognition wanted to know about the problem-solving ability of bumblebees. So they started with a ball in the center of a disc. Right by the ball was some sugar water, a great reward for a bee. Soon the bees got used to finding sugar water by the ball when it was in the center of the disk.

Then the scientists put the ball at the edge of the disk. The bees checked the center of the disc for sugar water. No luck. Then they checked the ball for sugar water. No luck.

Some very smart bees figured out what they had to do. They rolled the ball to the center of the disc and got a sugar water reward. (These bees, we think, were the Einsteins of the bee world.) Other bees watched this process—either observing the ball being moved by a real bee or by a plastic bee on the end of a stick pushed by a scientist. But one way or the other, the bumblebees learned by watching and solved the problem. Pretty good for an insect with a brain the size of a sesame seed. (All of this makes Pat want to become an insect cognition researcher so she can teach bumblebees.)

But we digress. We were talking about natural selection and how it works. Though the bees of a given species are similar, there's natural variation. They're all fuzzy, but some are fuzzier than others. They can all vibrate their wing muscles to warm up, but some are better at it than others.

Suppose that climate change makes a certain area significantly colder over a period of decades. The fuzziest bees and the ones that are best at warming up are most likely to survive and reproduce. Over time, that leads to fuzzier bees that are better able to tolerate the cold.

There are those who seem to think that losing a few bumblebees isn't a big deal. But here's the rub. For the natural selection to help the bees to survive, there needs to be a large enough population to offer enough genetic variation. If the fuzziest bees have been wiped out, they aren't around to help the bee population survive.

So maybe you're just thinking: "Oh, don't be ridiculous. Get real. It's not like we are likely to just wipe out all the bees in an area. I mean, there are lots of bees."

Tell that to the farmers in one remote Chinese province, where one hundred percent of the apple crop is pollinated by hand. The native pollinators are no longer up to the task, their populations diminished by a series of economic decisions.

The Chinese apple farmers didn't intend to wipe out their native pollinators. But apples are a valuable crop, so they cleared land to make more orchards, destroying nesting areas and food plants the native bees needed. They wanted better looking fruit to get a higher price, so they sprayed with pesticides, killing off more bees. Add to this the effects of climate change—more frequent rains, more cloudy days, cooler temperatures—these affect how many days the bees can fly and pollinate the crop. Put it all together and you get the unintended consequence: fewer bees where you need them.

The more sweeping the change, the more likely there are to be unforeseen consequences. But even tiny changes can also have giant consequences.

Take, for instance, a White House memorandum issued on Inauguration Day this January. The order froze all new regulations while the new administration reviews "questions of fact, law, and policy they raise." U.S. Fish and Wildlife Service, under authority of the Department of the Interior, had determined, based on scientific and commercial data, that the rusty patched bumblebee was critically endangered and in need of protection. The official designation as an endangered species was supposed to take place on February 10, 2017. That designation would trigger new regulations.

But because of the White House's directive, the rusty patched bumblebee was not added to the endangered species list on that date. As we're going to press the administration has unexpectedly allowed the listing, but the fate of the rusty patched bumblebee is still unclear.

So maybe now you're imagining a dystopic future without bees. You can still get mangos and guavas (both pollinated by bats), but apple pie is an insanely exotic and expensive treat, since each apple flower must be hand pollinated.

Don't stop there in your dystopian world view. This new world has few wild flowers. Birds and small mammals that eat nuts and fruits are gone—nothing to eat. And predators that fed on those birds and mammals? Many of those are gone, too. Fewer owls and hawks and foxes. (Grasses are wind pollinated, so grazers are okay.)

Here, in this bleak world, the gardeners who raise greenhouse tomatoes are strangely cheerful—an unintended consequence of the bumblebee's demise.

You see, some food crops do best with specific pollinators. Tomatoes, it seems, do best with bumblebees. Tomato flowers have pollen that has to be shaken out of the anther through little pores. Honeybees can't get it out. But bumblebees (and some other native bees) have a special trick called buzz pollination. The bee grabs hold of the flower and vibrates its flight muscles rapidly to vibrate the flower, causing it to release a cloud of pollen that settles on the bee's fuzzy body. The bee gets some pollen for food and carries some to another tomato flower.

If you are a tomato farmer and you have no bumblebees, what do you do? In the past, some commercial greenhouses have made use of handheld electric vibrators. They used them to buzz the tomato flowers.

So there's a happy unintended consequence. Without bumblebees in our imagined future, the sales of vibrators increase—allegedly because of the need to pollinate tomato plants. But vibrators have other uses, and the tomato farmers are cheerful.

People like to think in terms of cause and effect. We want things to be simple: You do X and you get Y.

But when it comes to natural systems, it's just not that simple. You do X and you get a cascading alphabet of effects. And some of those effects double back to become new causes.

That brings us back to unintended consequences. To have a hope of avoiding the monkey's paw of unexpected outcomes, we need to expand our thinking beyond cause and effect. We need to think about systems.

The honeybees, the bumblebees, and all the other bee species too numerous to name here are part of a complicated natural system. The system evolved over millions of years, and pulling one piece out of the system can cause all the other pieces to shift—sometimes subtly, sometimes more dramatically.

The world abounds in complex systems, where small changes can lead to large perturbations. In politics, unintended consequences seem particularly likely, since governments often work on a large scale, with no opportunity to test their assumptions. (Pat also has the theory that people who are confident enough to run for office and eager to have power are also likely to be overconfident in their own abilities, and more likely to blunder ahead regardless of the consequences.)

In economics, the inevitability of unintended consequences is recognized as a "law." According to the Concise Encyclopedia of Economics, "the law of unintended consequences, often cited but rarely defined, is that actions of people—and especially of government—always have effects that are unanticipated or unintended. Economists and other social scientists have heeded its power for centuries; for just as long, politicians and popular opinion have largely ignored it."

In today's political climate, it seems wise to remember this.
 

Pat Murphy and Paul Doherty recently published their first fiction collaboration, a story inspired in part by research for a past column. "Cold Comfort," a story about the melting of the permafrost, is available in Bridging Infinity, edited by Jonathan Strahan. It will be reprinted in Gardner Dozois's Year's Best Science Fiction: Volume 34. For more on Paul's work and his latest adventures, visit www.exo .net/~pauld. You can learn more about what Pat's up to at www .brazenhussies.net/Murphy.