Weird webs

Boffins were baffled in 2007 when trees at Lake Tawakoni in Texas were found entirely swathed in a giant spider web (2nd image). It was discovered by park superintendent Donna Garde, who took the photo and described, "At first, it was so white it looked like fairyland. Now it's filled with so many mosquitoes that it's turned a little brown. There are times you can literally hear the screech of millions of mosquitoes caught in those webs." Joseph T. Lapp provides a plausible explanation for the phenomenon in his "Spider Joe" videos. Orbweaver spiders were making their round webs, but because there were so many midges to feast on, they did not need to recycle the protein in the webs by eating them each night. At the same time, male longjawed orbweavers were encroaching on their webs in search of mates. As they traversed the tree from web to web, they left trails of their own silk, joining them into one giant shroud.

Now something similar is happening in Pakistan (1st image) after flooding in 2010. There, the spiders took to the trees to escape rising floodwaters, which have been slow to recede. As creepy as their giant webs are, they are trapping a remarkable number of mosquitoes and reducing the number of cases of malaria.