Natures wonders: Spider looks like a dry leaf (Introduction)

by David Turell , Saturday, November 19, 2016, 01:20 (2925 days ago) @ dhw

There are lots of biomimetic examples, but this spider is a newly found example and still not fully understood:

http://www.livescience.com/56910-leaf-mimicking-spider-found.html?utm_source=ls-newslet...

"about 100 spider species also sport physical features that make them appear inanimate and unappetizing, like a jumble of twigs, plant debris or a messy glob of bird poo.

"This is the first known spider species to be leaf-shaped. And its discovery was accidental, according to the study's lead author, Matjaz Kuntner,

"The scientists spied and photographed the unusual arachnid in 2011, while looking for other types of spiders in Yunnan, China. They found the individual — a female — on a twig, surrounded by dead leaves and with no web nearby. The researchers noted that her back looked like a living, green leaf, while the underside of her body was brown, mimicking a dead leaf, and a hairy, stalk-like structure protruded from her abdomen.

"The greenish-yellow underside of the spider resembles a fresh leaf, and the hairy, stalk-like structure curving from its abdomen makes it look even more like a plant.

"Leaves close by the female spider on the branch were attached with silk, which hinted that she had placed them there deliberately to further camouflage herself. However, additional observations would be necessary to confirm this behavior, Kuntner told Live Science.

"Having first noticed their rarity in nature, we talked to curators and established their overall rarity," he said. One similar specimen eventually emerged from a museum collection — a female that had been found in Vietnam. But the scientists suspected the Vietnam spider belonged to a known species in the Poltys genus, whereas the other two spiders likely represented a new species.

"There is still much to be learned about this enigmatic leaf imitator — and considering how difficult it was to find just the first two representatives, that's easier said than done. The authors concluded their study with the somewhat rueful observation that the mysterious spider's secretive habits and nocturnal lifestyle enabled it to successfully avoid not only predators, but researchers as well.

Comment: How did the spider decide to do this? If this deceptive camouflage is necessary, tiny steps of partial change would not be effective, suggesting it all happened in one jump, a saltation. Not by chance. Check out the pictures on the website. The hiding trick is amazing.