Gorgosaurus and Daspletosaurus

Hey everybody it’s been awhile but I forgot all of my login info for like a month now and have been itching to talk and so I leave you this report I made about a month ago so enjoy.

For this topic I wish to discuss late cretaceous North America, but more specifically I wish to talk about the coexistence of large theropod dinosaurs in the same environment. Now most of you know what I am talking about, but for those of you who don’t know I'll give a brief explanation of what I'm talking about. In North America during the late cretaceous (more specifically 80-70 million years ago) the Tyrannosauridae family saw the two great predators Gorgosaurus libratus, and Daspletosaurus torosus. These two Carnivorous theropods not only coexisted in the same environment, but thrived in it.

                                     Gorgasaurus

                                     Daspletosaurus

So down to the topic at hand. As most of you know there has been great debate in the paleontological community as to how these Tyrannosaurs were able to coexist. Some paleontologists speculate that Gorgosaurus lived at higher altitudes than Daspletosaurus. Others speculate that they had different diets because they were built differently. And many other speculations and ideas that over the years have been discounted by further discovery's in the "two medicine" and "dinosaur park" formations. And I think I've figured out why no one can get a speculation to stick on how these two coexisted. It's because they are looking too much at the two Tyrannosaurs and their differences instead of their similarities.

Ecology

The date for this look back at historical ecology we have to go back to 77 million years ago. This is the stage in the late cretaceous known as "Campanian" which was the stage when the Rocky Mountains began to uplift in the western part of North America. Before that uplift however the region where Gorgosaurus and Daspletosaurus both lived was a semi-temperate coastal floodplain with large rivers and wetlands but at times was prone to severe droughts. But during the uplift of the rocky mountains the resulting fluxuations in sea level changed the floodplains and wetlands into marine habitat, deltas, and lagoons though later wetlands returned at higher elevations. The rise of the Rocky’s also brought increased volcanic activity which left the region under ash whenever there was an eruption.

Prey

The prey of the region was as would be expected with Hadrosaurs, Ceratopsians, and other Tyrannosaurs and smaller predators.

Build

While Gorgosaurus and Daspletosaurus were both Tyrannosaurs, Daspletosaurus was more heavily built and a much more advanced Tyrannosaur. The Daspletosaurus is one of the Tyrannosaur species most suspected of evolving into the Tyrannosaurus rex.

Social Behavior

In this category both the Tyrannosaurs are believed to have lived in pack/family groups resembling that of wolfs in their group/family hierarchy.

Hunter/Scavenger

In this category both the Tyrannosaurs are believed to have been opportunistic hunters.

Personal Conclusion

Both Gorgosaurus and Daspletosaurus were apex predators for their shared times and shared territory’s. While many paleontologists point out their differences, it is there that they run into the same inherent problem. Many have compared the Daspletosaurus to a lion whereas the Gorgosaurus has been compared to the leopard or cheetah. I find those comparisons too unsimilar considering how similar the two species are. So I find better comparisons can be made by saying that the Daspletosaurus were the grey wolf, and the Gorgosaurus were the red wolf of the late cretaceous.

Well that’s me done and over leave comments below if you spot anything I may have missed but for now I need more than four hours of sleep.

Thanks for reading

References

http://en.wikipedia.org/wiki/Daspletosaurus#Paleoecology

http://en.wikipedia.org/wiki/Gorgosaurus

http://en.wikipedia.org/wiki/Dinosaur_Park_Formation

http://en.wikipedia.org/wiki/Two_Medicine_Formation