Animals that use electricity to search, hunt and kill
From the quirky platypus to the humble bee, a variety of animals use electricity to power up their wild lifestyles.
Electric eels can produce a killer shock
It’s probably the most famous animal to use electricity, but the electric eel isn’t an eel at all. This shocking river dweller belongs to the knifefish family and it lurks in the muddy waters of the Amazon and Orinoco basins of South America, where its electric abilities come in handy for navigating the murky environment.
Electric eels are capable of producing more than 600 volts of electricity – that’s five times the voltage of an average wall socket. Most of the fish’s body is dedicated to producing electricity, with only the front 20 per cent of its serpent-like anatomy containing vital organs.
Most of this creature’s electrical output is expelled in low-voltage pulses, which are used to detect the world around it (electric eels are more or less blind, so they use their electrical abilities in a similar way to bats’ echolocation). It also uses its electricity to stun and kill smaller fish. On rare occasions, humans have drowned after being shocked by an electric eel, a jolt that is said to be strong enough to knock a horse off its feet.
Platypuses find food using their electric bills
The platypus is a truly bizarre creature. Not only are these Australian critters weird to look at with their duck-like bills and beaver- like tails (so odd, in fact, that the scientists who discovered them thought they were being tricked with an elaborate hoax), they’re also some of the only mammals to lay eggs. This ability puts them into the monotreme family along with their cousins, the echidnas. But one of the platypus’ strangest quirks isn’t so obvious.
For years, researchers were befuddled as to how the semi- aquatic creatures find their food underwater, particularly considering the fact that they close their eyes, ears and nostrils while swimming. By analysing the creature’s bill they realised that the platypus’ signature accessory isn’t just for show – the digging beak contains over 40,000 electrical receptors, which are used to detect the tiniest movements of prey and locate living creatures with remarkable accuracy.
Sharks use electricity as a sixth sense
A shark’s sense of smell is incredibly acute, capable of sniffing out a single teaspoon of blood in an area of water the size of a swimming pool. But incredible smelling abilities aren’t the shark’s only skill: they also use electricity to detect their prey, scoping out meals by using receptors on their heads. These receptors have a rather catchy name – ampullae of Lorenzini – and they’re key to the shark’s hunting strategy, allowing them to sense electricity 10,000 times more effectively than other animals.
When a shark has determined that a meal must be nearby through its super scent, it will use its electrical sensors like a radar to scan the area until it locates the tiny electrical fields produced by all living creatures. It doesn’t matter whether the prey is buried in sand or hidden by rocks – by using electricity the shark leaves its victims with nowhere to hide.
Bees and flowers communicate via electric signals
We’ve known for a long time that bees are attracted to the bright colours and sweet smells of flower blooms, but it’s only relatively recently that scientists have learned of a less obvious method that flowers use to attract the pollinating insects: electricity.
Flowers use electricity to communicate with bees about their nectar reserves, enabling the insects to choose the best plants to feed at. By emitting a negative charge when bees fly near, the positively charged bugs detect an electrical signal, which advertises the flower’s potential for food.
Spiders build electrically charged webs to catch insects
Everyone knows that spider webs are sticky – it’s how the eight-legged predators catch flies and other bugs. Yet there’s more to the spider’s intricate creation; researchers have discovered that the arachnids conduct static electricity across the surface of their webs. This not only helps to ensnare small insects, it also actively attracts them. Bees and other flying insects produce a positive charge due to the fast movements of their wings, which causes them to naturally gravitate towards the electrostatic surface of a spider’s web.
The web bends towards the insect as it approaches; its static surface causes it to change shape as charged objects approach, making it more difficult for flying bugs to evade their grisly fate. However, some scientists have suggested that the trick can backfire: by detecting the static surface
of a web, insects may be alerted to a spider’s presence, helping them to avoid becoming ensnared and then eaten.
Words: Matt Ayres