The large size of Troodon’s eyes may have meant that in the Arctic it was able to outcompete other kinds of predator that were more common elsewhere. Fiorillo points to modern ecosystems where wolves and coyotes once co-existed but the wolf has been removed. ‘The coyote’s response is that they grow bigger. The top predator is removed, so they can expand into their niche space. There’s a modern basis for saying that’s what we are also seeing in Troodon.’
