What big eyes you have! Ostriches have the biggest eyes of any land vertebrates– roughly the size of a billiard ball.

Sketch and fact contributed by Amelia Munson

Source: Brown, L. H.; Urban, E.K.; Newman, K. (1982). “Ostriches and to Birds of Prey”. In Curry-Lindahl, Kai (ed.). The Birds of Africa. I. London, UK: Academic Press. pp. 32–37. ISBN 978-0-12-137301-6.