Lukas Holas is a photographer and graphic designer from Frydlant, Czech Republic. In a series on Behance entitled, Portraits of Animals, Holas expresses his love of animals with a collection of breathtaking black and white portraits.
The Eye of a Tree Frog. The film covering his eye is a nictating membrane that’s effectively an extension of its lower eyelid. It keeps his eye moist while he’s asleep. Because it lets in light, the frog can still detect predators while asleep.