Residents in a rural area of southeastern Brazil reported a sky full of spiders this week. Hundreds of eight-legged visitors have taken to the air, constructing a huge web ceiling that makes it look as if they are floating in mid-air. According to experts, hot and humid weather causes the arachnids to go airborne to catch their prey of insects and sometimes small birds. "There were many more webs and spiders than you can see in the video," Jercina Martinelli told a local paper.