Led by mechanical engineering student Guillermo J. Amador, the team built a small wind tunnel and tested three kinds of false lashes: commercially available eyelashes made from human hair; a synthetic mesh, and an impermeable paper ring. Inside each ring was a small aluminum disk, four millimeters deep, shaped like half of a chocolate coin wrapper. The researchers filled the disks with water to simulate the surface of an eyeball. Then, in a wind tunnel, they blew air at the simulation eyeballs for ten minutes while a scale weighed the water-filled disk to measure evaporation. The impermeable ring had the least evaporation, but would also obstruct the most vision. Of the options that would let a creature see out of its eyeballs, the human eyelashes worked best.