Have sauropod dinosaur, will travel.
A new species of sauropod in Egypt is helping fill in the blanks about the movement of dinosaur populations.
Mansourasaurus shahinae is a school-bus-sized titanosaur. Discovered in 2013 by a team of Egyptian and American researchers from Mansoura University, its weight would rivaled a grown African elephant. There’s also evidence it had osteoderms along its back. Badass, right?
This new African discovery is remarkable, particularly for its level of preservation. The fossil is, as the authors of the study put it: “the most complete terrestrial vertebrate specimen known from the PCC [post-Cenomanian Cretaceous] of the entire African continent.” But there’s more that makes this find important.
Dinosaur Biogeography and Vegetation
So, why does M. shahinae matter? As Mark Hallet and Matthew J. Wedel note in their book The Sauropod Dinosaurs: Life in the Age of Giants, the dispersal of sauropod populations across continents isn’t as simple as we might think.
The concentration, distribution, and isolation of sauropod populations during the Cretaceous is still debated. Their palaeobiogeography has been difficult to characterize, along with other dinosaur species.
Incomplete sampling may be partly to blame. However, much of the African fossil record is difficult to access. Conditions in places like Patagonia and the Rocky Mountains aren’t as common in Africa. As well, much of the geography is covered by lush vegetation.
For now, dispersal of Cretaceous dinosaurs remains clouded in uncertainty. Many mysteries about the end of these dinosaurs and the end of the Mesozoic still beg to be answered.
Understanding Sauropod Dispersal
M. shahinae can help us begin to answer some of these mysteries. Phylogenetics suggests close relationships between it and Eurasian titanosaurs. This, in turn, hints at dispersal routes between Eurasia and Africa.
These sauropods’ dispersal also may have happened after Africa split with South America. It’s then possible that sauropods and other dinosaurs moved between Eurasia and Africa more frequently than previously thought. And, this might have continued until the end of the Cretaceous.
What Else Could Be Out There?
If M. shahinae was moving all around during the Cretaceous, what does that mean? Did it just show up supremely late in Africa? Was it moving in response to climate cycles? Or, was this journey just an ancestral migration route? Whatever the answers, there are still two questions that stick out to me:
- Are there more species that made it back and forth in the same way?
- If not, what happened with M. shahinae?
We only understand one portion of these questions so far. Because M. shahinae is in close phylogenetic proximity to Eurasian titanosaurs, the idea of an isolated Africa is hard to argue. And, if M. shahinae could do it, it’s natural to infer other dinosaurs did so as well.
For the moment, these ideas are still up for debate. Without more specimens of M. shahinae, issues of incomplete sampling stop us from drawing more definitive conclusions.
Regardless, this is a super exciting find. Hopefully it opens the doors to even greater paleontological discoveries in Africa!