Scientists discovered a giant zipper running through the polar ice sheets! No, seriously: it's a pattern of interlace when ice sheets meet each other.
"A surprising pattern, much like the meshed teeth of a zipper, is frequently seen when floating ice sheets collide," said John Wettlaufer, professor of geology & geophysics and of physics at Yale. He and his colleague Dominic Vella of Cambridge University in England demonstrated the underlying principle for the observation. Further, they suggest that the process can work for any materials that share particular physical characteristics of thickness and flexibility.