How does a great gray owl do that? Now we know. Martin Meissner/AP hide caption toggle caption Martin Meissner/AP Shots - Health News How Owls Spin Their Heads Without Tearing Arteries January 31, 2013 Owls can turn their heads 270 degrees without injuring themselves. That's more than twice as far around as humans can safely handle. Nifty adaptations in owls' vertebrae and blood vessels make it possible.