They may wekk evolve again, given the right circumstances. Giganticism in both predator and prey is a response to plentiful food. It happened with both dinosaur

They may wekk evolve again, given the right circumstances. Giganticism in both predator and prey is a response to plentiful food. It happened with both dinosaurs and mammals. By the same token, animals respond by evolving into smaller forms in food sparse environments. On the Indonesian island of Flores, both hominids and elephants became tiny.