Image courtesy National Geographic
I've just come across this and thought it absolutely fascinating.
One of the astonishing side effects of the 2010 flooding in Pakistan was that in some areas millions of spiders climbed into the trees to escape the rising flood waters. Because the waters took so long to recede the trees became cocooned in spider webs, a phenomenon that had not been seen before in this area.
The scene is quite surreal and strangely beautiful.