[You must be registered and logged in to see this image.]Constructing a decoy many times its size, the spider can lure a substantial meal into its web or scare off smaller attackers it doesn’t want to tussle with. One of the decoys is pictured above.
A biologist working in the Peruvian rainforest has stumbled upon the first evidence of a tiny spider with a deadly clever game: constructing its own decoy.
“It looked so spiderlike, with eight legs. The spitting image of a spider,” Phil Torres told the Toronto Star of his discovery.
While Torres, a specialist in entomology, had never seen a species like it, he’s not ready to declare a new biological discovery until science can verify his finding.
“It may just be a very evolved spider that can follow rules.”
Those rules have given the spider, no bigger than a lentil, a powerful weapon against predators, Torres said.
Constructing a decoy many times its size, the spider can lure a substantial meal into its web or scare off smaller attackers it doesn’t want to tussle with.
The decoy is painstakingly pieced together from twigs, leaves, uneaten parts of other insects and rain forest mulch, Torres said.
As he approached the web, he saw what he thought was a dead spider. Then it started to move. Inching closer, he spotted “this little guy going like crazy” in one corner, jiggling the web to animate its decoy and fool its prey.
After finding the first one, Torres managed to spot 25 in a kilometre-square plain area near the ecotourism Tambopata Research Center in southeastern Peru and none outside that area. Not all were perfect.
“Let’s just say the spiders had different artistic talents. A few of them had only four legs and weren’t quite symmetrical. It still does seem to do the trick.”
Other species of spiders make little balls that look like themselves curled up and dot 10 or so of them around the web, confusing a hungry wasp that has to figure out which are fake and which are the real, sleeping spider, Torres said.
This is the first he’s seen or heard of one that constructs large-scale Potemkin models.
“This behaviour has never been recorded. It’s not a rare thing for spiders to make designs in their web or to put debris in their web. This does appear to be the most advanced design.”
Torres, who has worked with the research centre for a year and a half, will return to the rainforest in January from his home base in Los Angeles to collect a sample for entomologists to examine and determine whether this is a new species with a highly evolved idea of self-defence.
Source: thestar.com
Fri Dec 21, 2012 5:55 am
Calendar
