(Image credit: Lon&Queta)
The ob-weaving spider you see above already had a fully-finished web ready to trap dinner. But it went back and gussied up the place with a lovely geometric pattern anyway. So did this St. Andrew's Cross spider, which was named for this kind of decoration. Charlotte would be proud.
(Image credit: Amos T Fairchild)
Spider of widely-varying species do this. The decoration itself is called stabilimentum, because scientists once thought it was done to make the web more stable. Arachnologists have abandoned that idea, but there's no agreement on why spiders decorate their webs. It could be because they are in a web-building mood and can't stop. Or maybe it makes them look bigger, or conversely, serves as extra camouflage. It could be to attract certain kinds of prey, or even to help the spider regulate its own temperature. Maybe they are showing off for mating purposes. But since this behavior has been observed in different species, they could have different reasons. Its even possible that spiders just like the look. Read about spiders and their stabilimenta at The Ark in Space. -via Everlasting Blort