Humeral bone strength and hunting strategies in dromaeosaur and troodont dinosaurs

Dromaeosaur and troodont dinosaurs were small predatory theropods. Dromaeosaurids had stronger feet than troodontids and are believed to have used a stealthy ambush predatory strategy, adapted for relatively large prey. By contrast, troodontids had a longer metatarsus, presumably, allowing for speed. This allowed for a more precise, but weaker grip. This suggests that they were swift runners who probably took relatively smaller prey. Dromaeosaurids are believed to have attacked larger prey animals than the troodontids. In this work, we find that the dromaeosaurids had stronger humeri (i.e., with a larger section modulus) than the troodontids. This is consistent with the hypothesis that the dromaeosaurids attacked larger prey than troodontids. Humeral stresses are expected to be larger when engaging a larger prey animal.