You can place all the dinosaur remains from Arabia on one table, which is what they used to say about human fossil before several tens of thousands of human ancestor bits and pieces were eventually accumulated. But this does not mean that we don’t know much about Arabian Dinosaurs. Back in the days of dinosaurs, the big triangular-shaped piece of land known as Arabia was firmly attached to, and indeed, totally part of, Africa. The Red Sea, which separates Arabia and Africa, is recent.
The newly reported tracks are also interesting because there is more than one species represented. In particular, there is a bipedal trackmaker and a quadrupedal trackmaker. They were found in sediments dated to the end of the Jurassic or the early Cretaceous. This dating is based on the fact that the geological formation contains numerous (small, non-dinosaur) organisms that are totally extinct today but that are know to have existed at this period of time.
The researchers identify the biped as an ornithopod type dinosaur. These are the dinosaurs that walked around on two legs like Tyrannosaurus or the famous raptors. But which species of ornithopod? They’re not saying, as there is not enough information to be sure.
The quadruped trackmakers seem to have a large and a small variety. They seem to have been traveling together in a herd. They are not very well preserved but the researchers are calling them neosauropods. In particular, they are suggesting that these trackmakers were nontitanosauriform.
What the heck does that mean?
Well, the sauroforms are the kind of dinosaur typically walking around on four legs, the long necked ones you see in dinosaur movies munching the tops of trees. The most common dinos of this type in the southern continent (of which this bit of Africa/Arabia was part) had a wide stance, and were often large (titanic). The dinos at this trackway are in a different group with a narrower stance, such that the left and right tracks are very close together. This makes them neosauropods.
This find is also potentially interesting because there is a hypothesis that about the time that this trackway seems to have been made, sauropod-dominated dinosaur communities gave way to ornithopod-dominated communities. This particular trackway, in and of itself, cannot address that hypothesis. But the geological formation in which these tracks were found is apparently quite large and more tracks were likely to be found. More data, more understanding of the overall pattern of evolution.
No evidence of humans were found in association with these tracks. If you are looking for human-dinosaur associations, we can’t help you. Nothing to see here. Move along please….
Schulp, A.S., Al-Wosabi, M., Stevens, N.J., Stepanova, A. (2008). First Dinosaur Tracks from the Arabian Peninsula. PLoS ONE, 3(5), e2243. DOI: 10.1371/journal.pone.0002243