A new study shows that dinosaurs left Europe in droves during a strange period of migration in the Early Cretaceous.
Groups of dinosaurs left the continent and there were no arrivals to replenish the population, according to the study. Researchers used “network theory” in order to come up with the first visual representation of dinosaur population movements during the Mesozoic Era.
Emigration patterns of dinosaurs revealed using network theory
The study shows an unusual pattern of emigration from Europe which supports previous research that claimed dinosaur migration continued after Pangaea split into separate land masses.
“We presume that temporary land bridges formed due to changes in sea levels, temporarily reconnecting the continents,” said Alex Dunhill, a researcher from the University of Leeds and first author on the study. “Such massive structures – spanning, for example, from Indo-Madagascar to Australia – may be hard to imagine. But over the timescales that we are talking about, which is in the order of tens of millions of years, it is perfectly feasible that plate tectonic activity gave rise to the right conditions for such land bridges to form.”
Using the Paleobiology Database, which records every documented and available dinosaur fossil, the scientists cross-mapped fossil records from dinosaur families across different continents and time periods. The resulting visual reveals migration patterns.
Scientists confused by findings
Some areas of the world have more widely studied fossils than others, so the scientists applied a filter to the data. This means that only the first instance of a connection between a dinosaur family over two continents was counted.
The first conclusion of the study is that dinosaur migration continued after Pangaea split into separate continents. The second is that dinosaur families left Europe during the Early Cretaceous period without being replaced by others.
“This is a curious result that has no concrete explanation,” Dunhill said. “It might be a real migratory pattern or it may be an artifact of the incomplete and sporadic nature of the dinosaur fossil record.”
Network theory moving into new areas
Further research is needed in order to work out why dinosaurs were leaving Europe and not being replaced. It certainly seems odd that they were leaving without being replaced. However this could be shown not to be true if further study fills in some of the gaps in the dinosaur fossil record.
Network theory is more commonly used in computer science to analyze internet data. However it has also been put to good use in biology research.
“Network theory has been studied in physics for a number of years, however it is finally permeating into other disciplines,” said James Sciberras of the University of Bath and co-author of the study. “This idea that most things can, and should, be considered in the context of the whole system will lead to some exciting new findings in a wide range of fields.”
The full findings of the study were published in the Journal of Biogeography on April 25. Scientists around the world continue to make interesting discoveries related to dinosaurs, with a baby dinosaur fossil recently found in Madagascar.
The fossil provides valuable information about the growth of sauropod dinosaurs and the extent to which parents looked after their children. In the case of the Rapetosaurus evidence suggests that it was left to survive on its own shortly after birth.
One reason for this is the huge difference in size between the chihuahua sized offspring and the parents, which were about as big as a fire truck.