Peace Among Hell's Kings

A male Tyrannosaurus rex and Dakotaraptor; the two apex predators of the Hell Creek ecosystem of the Late Cretaceous, share a rare moment of peace as the two predators wonder out of the forest onto the plains in search of prey. The mutual tolerance between the two large predators may be due to a mutual symbiosis between them; the as both carnivores search for food they rely on each others keen eyesight as well as the rex's impeccable sense of smell to find it, and work together to either take the prey animal down or drive away the other predators and take over the carcass; sharing the spoils. This teamwork can be seen in individuals who do not have packs of their own species to hunt with. Of course this behavior only occurs when a lone Tyrannosaurus and Dakotaraptor are in need of food and are by themselves unable to secure a meal. Otherwise the two predators avoid each other, and when they do meet, usually only one animal walks way alive.
Setting: South Dakota, 66,000,000 B.C.