April 26, 2016

Sarah Knapton

It is probably Europe’s earliest migration crisis. Around 125 million years ago huge numbers of dinosaurs began to flood out of Europe and palaeontologists do not know why.

Scientists at Leeds University used computer modelling of the fossil record to work out the movements of dinosaurs during the Mezozoic Era, from 225 million years ago to 65 million years ago and found an odd exodus in the middle.

They used the Paleobiology Database which contains every documented and accessible dinosaur fossil from around the world to work out the migration patterns of species.

Some regions of the world, such as Europe, have extensive fossil records from a long history of palaeontology digs, while other parts of the world have been largely unexplored.

To help account for this disparity in fossil records, which could otherwise skew their findings, the researchers applied a filter to the database records to only count the first time that a dinosaur family connection occurred between two continents.

The research also showed that all connections between Europe and other continents during the Early Cretaceous period, 125-100 million years ago, were out-going.

While dinosaur families were leaving Europe, no new families were migrating into Europe for 25 million years, before they began to return.

"It might be a real migratory pattern or it may be an artefact of the incomplete and sporadic nature of the dinosaur fossil record."

The study, published in the Journal of Biogeography, also backs up previous research that found dinosaurs continued to migrate to all parts of the world after the 'supercontinent' Pangaea split into land masses that are separated by oceans.

"We presume that temporary land bridges formed due to changes in sea levels, temporarily reconnecting the continents," added Dr Dunhill.

"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."

http://www.telegraph.co.uk/science/2016/04/24/dino-brexit-bizarre-migration-saw-dinosaurs-flood-out-of-europe/