As a rule of thumb, animals avoid smacking into things. But rules of thumb, like the actual thumbs of unskilled carpenters, are made to be broken. And so researchers at Sweden's Lund University were recently surprised to find that the visual systems of some animals actually make collisions within their environment more, rather than less, likely.
The Lund scientists have a long-standing interest in how insects see the world, nay, the universe. Some members of the team were in on last year's Ig Nobel Prize–winning paper “Dung Beetles Use the Milky Way for Navigation,” which appeared in the journal Current Biology. The beetles look up, see the stream of stars and think, “That's the way I roll.”
The new Lundian research effort observed how bumblebees, representing flying critters, move through the dynamic fluid of air versus how zebra fish, in this corner for all the swimmers, find their way through the dynamic fluid of fluid.
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As expected, the bees adjusted their flight to avoid contact with stuff. The fish, on the other fin, “move closer to the wall that provides the strongest visual feedback.” That quote is from the write-up of the research in Biology Letters, “Control of Self-Motion in Dynamic Fluids: Fish Do It Differently from Bees.” It's a good title, but it kind of gives away the ending, like if the movie had been called The Hunger Games: Don't Worry, Kat Wins.
Of course, bees zip around in a sun-dappled world of clear skies and vibrantly colored flowers, if Nasonex commercials have taught me anything. But fish often slog through a turbid seascape of limited visibility. So if they see seashells by the seashore, it seems like they'll swim toward them, accepting the risk of collision in return for having landmarks for just where the heck they are.
In summary then, bees fly around like Charles Lindbergh, looking down from up high while keeping clear of any obstacles in their paths. Meanwhile fish have evolutionarily adopted the strategy of those 15th-century European explorers who limited their voyages to slowly moving southward along Africa's western coast. Their motto: “I'd rather bump into a continent than be lost at sea.”
Speaking of bumping into things, Utah State University scientists and government researchers have created a smartphone app for reporting incidents of that special breed of unhappy driving experience where one party ends up pumping out adrenaline and the other party shuffles off its mortal coil. The app is called the WVC Reporter, where “WVC” stands for “wildlife-vehicle collisions.”
Wildlife agency folks and scientists currently try to tally the deaths by traveling around and writing down things they observe. A few states also have Web sites for reporting roadkill. But a smartphone-based and crowdsourced system of noting these frequent events could increase, by leaps and bounds (and I mean that), the data available to track the carnage.
And a bloody mess it is. The Utah squad, in a paper describing its app in the journal PLOS ONE, says that there are up to two million impromptu encounters between large animals and people behind wheels every year in the U.S. That figure, limited to big beasties, would not include the time I was a passenger in a Volkswagen Rabbit that hit an actual flesh-and-blood rabbit.
The Utah app inventors also cite a million road-killed vertebrates every 24 hours in the U.S., a daily vehicular-begotten, greasy-grimy, gopher-gutted Guernica. And some 200 humans wind up dead annually: Mack Truck versus mule deer is one thing, Mini Cooper versus moose quite another. So people have an enlightened self-interest in trying to reduce these highway lowlights.
If loads of us can use smartphones to play Angry Birds, maybe a few hundred thousand citizens can click on their mobile devices (not while driving) to efficiently help researchers turn dead possums into data points. Then we will know better where to install fencing and greenways that would keep America's car grilles fur-free.
