This seems to be essentially a chase movie, with the chasers being various
ancient creatures, including mammoths, a sabretooth tiger and some
giant birds that we don't know the name for.
The New York Times reports how two new aviaries for vultures, brought to the brink of extinction by exposure to veterinary drugs, are being built, so that the
ancient tradition of leaving corpses in so - called Towers of Silence to be picked apart by the
giant scavenging
birds can resume.