This wonder of nature is a urodid moth cocoon. What advantage does this screen offer that a full cocoon doesn't? Phil Torres, a biologist, speculates:
I couldn’t find a lot of literature on these guys, but my best guess is the almost 1 foot long silk string it hangs from and the detailed lattice structure would do well to protect against ants while minimizing investment in an all-encompassing cocoon as many moths have.
Link -via Lustik | Photo: Jeff Cremer