You might think you're impressive because you can parallel park, but can you punch faster than a bullet? The mantis shrimp can, accelerating its strike faster than a .22 calibre bullet. These crustaceans are armed with a hammer-like dactyl club on each side, storing energy in elastic, spring-like structures held by latch-like tendons. When released, the energy propels the club forward with explosive force, so fast it boils the surrounding water, creating a cavitation bubble that collapses into a second shock wave. Researchers recently discovered the shrimp survives its own blow thanks to a 'phonic shield' that filters stress waves. So next time you crack your knuckles, consider the mantis shrimp cracking aquarium glass.
Spiders have been known to travel miles by ballooning on a single silk strand. For years, we assumed it was the wind. But Bristol researchers discovered they're actually using electrical fields. In a sealed chamber with no air currents, spiders took off when an electric field was present, the repulsion on the charged thread providing lift. Turn off the field, and they come down. Spiders have tiny hairs called trichobothria that sense electric fields, like human hairs rising with static. When the field is strong enough, they climb to a twig, spin a line, and take off. Sailors sometimes find them out at sea, riding the breeze. So next time you see a spider, remember: it's not just a creepy crawly, it's an electrified aviator.
Paper wasps can perform logical deduction, previously thought to be the domain of complex nervous systems. In a study, wasps in a rectangular arena had to choose between two regions: a 'safety zone' and one that delivered a 'slightly unpleasant' shock of 0.4 volts. The arenas were painted different colours in a strict order, and the wasps inferred which colours indicated electrification to a statistically significant degree. As scientists told the New York Times, the wasps 'are organizing all those pairs into a linear hierarchy in their head'. So next time a wasp ruins your picnic, remember it's probably smarter than you.
Sea urchins, essentially purple blobs with spines, can drill holes into rock with their teeth alone to make safer homes. They 'literally eat through stone', according to the University of Wisconsin-Madison. But even more peculiar, their teeth never go dull - they are 'one of the very few structures in nature that self-sharpen'. The urchin's five teeth constantly scrape rock, producing up to 200 tonnes of sediment per hectare. Future self-sharpening tools could be inspired by these spiky drillers. So the next time you need a hole in a rock, just ask a sea urchin.
One invertebrate has shown it can learn from experience without a central brain. Caribbean box jellyfish (Tripedalia cystophora) are tiny - about one centimetre in diameter - and swim near the surface during the day, sinking at night. A couple of years ago, New Scientist reported that researchers from Kiel University in Germany designed an experimental environment mimicking their mangrove-rich habitat. They placed a fingernail-sized jellyfish in a round tank with white and grey stripes to resemble mangrove roots. By the end, the jellyfish had learned about their tank and 'had cut their crashes in half and quadrupled their successful swerves'. So even a brainless blob can learn to avoid obstacles, which is more than we can say for some drivers.
Perhaps most amazingly, some fruit flies can be beheaded and still live normally for several days, because they have mini brains in each joint. Researchers at the University of Pennsylvania studied headless fruit flies' responses to light, preparing CO2-anesthetised flies and shining a microscopic light on them, to which they squirmed. Another study proposed that light-responsive cells enable larvae to sense light and move out of danger. Headless flies maintain posture, walk around, entrain new circadian rhythms, and learn to avoid shocks - sometimes even faster than flies with heads. They were even able to fly in some cases. So if you ever lose your head, remember: fruit flies have got you beat.
It's Invertebrate of the Year again! From 3-12 August, every day we'll profile one of thousands of amazing invertebrates nominated by readers. Then voting opens for your favourite. Get in touch with thoughts and ideas at environment.desk@theguardian.com with 'Invertebrate' in the subject line. Because nothing says 'celebration' like a slug.