STL Science Center

STL Science Center

31 December 2011

Pictures of a Gorgosaur

©Michael Skrepnick
Images of Gorgosaurus tend to look a lot like its tyrannosaur brethren. That, of course, is okay considering that Gorgosaurus is a tyrannosaur and all of the family looks quite similar whether they're from America or Asia. The characteristic appearance of the animals makes them highly distinguishable from other types of dinosaurs but kind of makes it difficult, at times, for the laymen to tell the difference. As an example, Skrepnick's Gorgosaurus is very well done and has enjoyed a good meal which the Bambiraptor in the foreground is also clearly enjoying. To most this is a typical tyrannosaur and I'll bet nine out of ten people would say its a T. Rex based on the arms and general look of the skull. However, that is where we start our inspections to decide what sort of animal this is. The skull is elongated and blunt nosed as opposed to the boxy T. Rex head. That clue is easy to collect even from a distance, and it can be seen without looking at the bones.
©Alain Beneteau

Beneteau's work shows the skull at less of a distance and we can clearly see how it is elongated in both the standing juvenile and the resting adult; also note the lacrimal ridges of bone above the eyes. Making a reasonable assumption based on assuming that the entire animal is drawn to correct proportions we can see that the tibia and femur are of about equal length. This gives us clues to draw conclusions about the speed of the animal. In most speedy animals the tibia is longer than the femur and the ratio can go closer to 1:1 and still be considered a quick animal. Considering that this animal's bones are approximately equal length we can assume it had the ability to move quickly if not fast. The juvenile, however, appears, and both adult and juvenile bone sizes have been noted in specimens, to have a longer tibia than femur, meaning that these dinosaurs were probably fairly speedy when they were younger.

Rachel Clark herself has said that this drawing is outdated and needs to be updated. I haven't seen any updates on it online. However, it highlights the sub-adult specimen very well whether she thinks it grossly outdated or not. The skull is wonderfully elongated, as would be the actual case with the animal. The lacrimal ridges above the eyes are very plain to see as well. Additionally, the structure of the skull that can be inferred by ridges and placement of characteristics of the face aligns with the circular rather than oval placement of the eyes in the head of Gorgosaurus, a feature which separates this dinosaur from other tyrannosaurs. The tibia-femur ratio is much closer to an adult specimen, which fits well with the assumption that this is a later juvenile of the species. All said and done, outdated or not, this is a wonderful drawing.

No comments:

Post a Comment