Robert Hooke, eye of a fly, Micrographia, 1665. Hancock Collection, USC.
Don’t worry, it’s painless. Aeon Films has posted a four minute short on mathematical relationships in nature, from the nautilus shell to floral architecture. For those interested in a discussion of the role of math in modern biology, Joel Cohen’s 2004 essay in PLOS is a good start. The title says it all: