“The image of the prey is getting bigger, but if it’s always on the same spot of the retina, the dragonfly will intercept its target,” said Paloma T. In a similar manner, as a dragonfly closes in on a meal, it maintains an image of the moving prey on the same spot, the same compass point of its visual field. If you’re heading north on a boat and you see another boat moving, say, 30 degrees to your right, and if as the two of you barrel forward the other boat remains at that 30-degree spot in your field of view, vector mechanics dictate that your boats will crash: better slow down, speed up or turn aside. Olberg of Union College, who reported the research with his colleagues in Proceedings of the National Academy of Sciences. The scientists found evidence that a dragonfly plots its course to intercept through a variant of “an old mariner’s trick,” said Robert M. With the aid of that neuronal package, a dragonfly can track a moving target, calculate a trajectory to intercept that target and subtly adjust its path as needed. Other researchers have identified a kind of master circuit of 16 neurons that connect the dragonfly’s brain to its flight motor center in the thorax. One research team has determined that the nervous system of a dragonfly displays an almost human capacity for selective attention, able to focus on a single prey as it flies amid a cloud of similarly fluttering insects, just as a guest at a party can attend to a friend’s words while ignoring the background chatter. In a string of recent papers, scientists have pinpointed key features of the dragonfly’s brain, eyes and wings that allow it to hunt so unerringly. “It would have happily kept eating,” she said, “if there had been more food available.” Stacey Combes, who studies the biomechanics of dragonfly flight at Harvard, once watched a laboratory dragonfly eat 30 flies in a row. Dragonflies may be bantam, but their appetite is bottomless. “It almost looks like a wad of snuff in the mouth before they swallow it.” May, an emeritus professor of entomology at Rutgers. “They’ll tear up the prey and mash it into a glob, munch, munch, munch,” said Michael L. When setting off to feed on other flying insects, dragonflies manage to snatch their targets in midair more than 95 percent of the time, often wolfishly consuming the fresh meat on the spur without bothering to alight. Yet they are also voracious aerial predators, and new research suggests they may well be the most brutally effective hunters in the animal kingdom. Great white sharks have 300 slashing teeth and that ominous soundtrack, and still nearly half their hunts fail.ĭragonflies, by contrast, look dainty, glittery and fun, like a bubble bath or costume jewelry, and they’re often grouped with butterflies and ladybugs on the very short list of Insects People Like. African lions roar and strut and act the apex carnivore, but they’re lucky to catch 25 percent of the prey they pursue.
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