Spiders, inspiring kinky sex and Celtic monuments

If they did not have to mate with females, male spiders would certainly avoid them altogether. Females are larger, more aggressive, and often eat their suitors before or after sex. Male nursery web spiders have a more legs-on approach: they tie the female down with shackles of silk. These "bridal veils" have long been suspected to help males avoid becoming a sexual dessert. But this idea was not empirically tested until February 2016.

In 2013, photos of silken structures comprising a vertical pillar surrounded by an intricate fence of white were uploaded to Reddit and Facebook. They went viral, passed around the public and sent to expert entomologists. After three days, a tiny spider popped out. Silkhenge is a spider egg sac. The species remains a mystery, however.

And my personal favourite :

By crawling backwards along this dragline, net spiders – colloquially known as slingshot spiders – convert their web into an elastic cone, with themselves at the centre. And there they wait, until they detect a nearby fly on the wing. "For a long time, people thought that if something is vibrating nearby they would activate the slingshot," says Torres. "But most studies have now indicated that they wait for something to fly into the web." When this happens, the spider lets go of the coiled up dragline, firing itself – and the web – at high speeds into its prey.
http://www.bbc.com/earth/story/20160617-forget-webs-spiders-also-make-slingshots-and-silkhenges