Did dinosaurs love to chew on dinosaur legs? What did Gorgosaurus eat for its "last supper"?

The study of Tyrannosaurus Rex and its relatives has always been a topic of great interest to the academic community and the general public. In recent years, research on the origin, individual development, population ecology, and corresponding biomechanics of Tyrannosaurus Rex and its relatives has emerged.

Late last year, a study on the diet of juvenile tyrannosaurid dinosaurs came to light. The study reported that a juvenile Gorgosaurus, a close relative of Tyrannosaurus Rex, had eaten two Oviraptorosaur hind legs, and the bones of the food were preserved in its fossil body.

The Gorgon fossil (in this study) and the bones of the food it ate in the red box

What is a Gorgon Dragon?

Gorgon belongs to the Tyrannosauridae family of the Saurischia order, and further subdivided into the Albertosaurinae subfamily. It has many differences from the Tyrannosaurus Rex which we are familiar with, but overall it is still relatively close, similar to cattle and sheep in the same family but different subfamilies, saber-toothed tigers and kittens, us Homo sapiens and orangutans, golden eagles and black kites (black kites are commonly known as eagles), modern white rhinoceros and the extinct nearly hornless rhinoceros, etc.

Judging from the skull, Gorgon has a more prominent " tear horn " than Tyrannosaurus Rex.

In terms of size, Gorgosaurus is also smaller. It is eight or nine meters long and weighs two or three tons, which is not very large in the Tyrannosaurus family. In comparison, the Tarbosaurus and Zhuchengtyrannus discovered in China, as well as the family "patriarch" Tyrannosaurus, are much heavier.

The author photographed the Tyrannosaurus Rex model in the Shanghai Natural History Museum. Note that its lacrimal horn is relatively inconspicuous.

The skull of a Gorgon dragon. Note the sharper lacrimal horn. Image source: Wikipedia

Gorgon appeared about 76 million years ago . At that time, North America was somewhat similar to the North America where Tyrannosaurus Rex lived. A group of large ceratopsians and hadrosaurs provided a lot of food for "predecessors" tyrannosaurids such as Gorgon and Daspletosaurus.

During the time from the appearance of Gorgosaurus to the end of the dinosaur era, Tyrannosaurus mcareensis and the most familiar Tyrannosaurus rex also appeared one after another ( Tyrannosaurus rex was discovered earlier and often appears in various film and television works).

Restoration of the Gorgon Dragon, source: Wikipedia

Although small in size, Gorgon is already a typical member of the advanced Tyrannosaurus. Its skull is solid and strong, and its cervical vertebrae have become thicker than those of the small primitive Tyrannosaurus . It is no longer the "little thieves" of the former Tyrannosaurus with thin heads and small stature.

The representative of the primitive Tyrannosaurus - Dilong the strange, the fossil was found in the Jehol Biota of the Early Cretaceous, only the size of a dog, the author took this photo at the Tianjin Natural History Museum

The "food" eaten by the Gorgon Dragon mentioned at the beginning was Citipes , which weighed only a dozen kilograms when grown. It was a large member of the Oviraptoridae family, but in terms of size, it was just a small dwarf compared to its relatives such as Anzusaurus and Gigantoraptor, which could grow up to 8 meters long.

The foot skeleton of the Jaguar, source: Wikipedia

Note: The bite force of the rear end of the mouth of Gorgosaurus has been measured to reach 13,000 Newtons. The characteristics of their occipital bones, infraorbital process structure, distal expansion of the scapula, and different numbers of teeth in the maxilla are the corresponding standards for distinguishing them from other tyrannosaurids. In addition, the distribution strata of Gorgosaurus are the Dinosaur Park Formation and the Judith River Formation (the latter is the stratum where Medusaceratops was found).

The Adventures of the Gorgon Dragon

Of course, if you look at this discovered Gorgon "child", you may feel that it is not very strong, after all, it has not grown up yet.

Comparison between adult and juvenile Gorgon dragons and humans, source: Wikipedia

Two eaten Gaddisaurus and this young Gorgon dragon compared to a human

If this Gorgon "child" could survive, it might have started hunting larger herbivorous dinosaurs when it was about 600 kg, and fully grown around 20 years old, as were many other tyrannosaurids. When it grew to 300-400 kg, it might have encountered a young and strong Daspletosaurus.

Compared with Gorgosaurus, Daspletosaurus had a wider snout, and the ecological niches of the two may be staggered - Daspletosaurus preyed more on ceratosaurians, while Gorgosaurus may have mainly preyed on hadrosaurs.

Other studies have found that the microhabitats of their habitats may be different (just as lions and tigers have historically been distributed in the same area in India and other places, but the two rarely meet, and the density of plants in their places is different). Some areas where juvenile Gorgon fossils have been unearthed (that is, their corresponding breeding grounds) often have fewer Daspletosaurus fossils, indicating that the two are likely to choose to live in different places and choose different habitats.

Fossil of the robust Daspletosaurus, source: Wikipedia

The strong Daspletosaurus preying on the ceratopsians, source: Wikipedia

A brief talk on eating chicken drumsticks

In the process of discovering the Jaguar, this Gorgon may be a picky eater, choosing a juvenile Jaguar that is much smaller than itself. The part it eats is also very "picky", directly eating the leg with relatively more skeletal muscle.

This reminds us that today, when polar bears hunt seals smaller than themselves, they will choose to eat the energy-rich fat layer of the seals first.

Corresponding fossil structures

The green and blue parts are the legs (and tail vertebrae) of the eaten Zygopodus.

We still don't know why they are so picky, but it may be to make efficient use of the best meat from their prey. Or maybe it's the year when it's easier to find a Gorgon, so the Gorgon children are picky eaters.

Brown bears will eat the caviar from the fattier parts of salmon during the height of the salmon season, but as the salmon season winds down, they will choose to eat the fish in big mouthfuls without wasting any of the fish's flesh.

American black bear eating salmon: I love eating fish just like my older brother, so I'm here to take advantage of the salmon craze

The young Jaguar that was eaten weighed only about the same as two red junglefowl. Red junglefowl is the chicken we usually eat (domestic chicken is a subspecies of red junglefowl), but the chicken legs are different from those of Jaguar.

If you look closely at the chicken's calf (also known as the drumstick), you'll find that the chicken's fibula has degenerated into a very small size (the same is true for other modern birds). As a maniraptoran, the fibula of the Japonosaurus is relatively long, which is a more obvious primitive feature.

Turkey skeleton specimen, the green part is the tarsometatarsus, taken by the author at the National Zoological Museum

Oviraptorosaur skeleton, source: pixabay

The green part of its skeleton is the lower leg, of which the fibula is relatively large and the degree of degeneration is not serious.

This precious Gorgon fossil is like a window through time and space, leading us to take a deep look at the past of that distant and mysterious world. The prehistoric ecology at that time is surprisingly similar to the natural world at this moment, and the eternal predation behavior is a vivid interpretation of the laws of nature and the cycle of life.

References

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