We have found, however, that this incredible diversity is underpinned by a hidden mathematical rule that governs the growth ...

Kathleen Garland receives funding from the Australian Government, Monash University and Museums Victoria ... cascade growth rule. While rare, a few birds we studied were rule-breakers.

While rare, a few birds we studied were rule-breakers. One such rule-breaker is the Eurasian spoonbill, whose highly specialised beak shape helps it sift through the mud to capture aquatic life.