Jorge Gonzalez
A team of researchers believes that the reason why we haven’t found older dinosaur fossils is because they are in places that are very difficult for scientists to access.
The oldest fossils on record are from around 230 million years ago. But these animals, which were part of the ancient Gondwana region, south of Pangea, appeared to have been evolving and dispersing around the world for millions of years.
Now, a new one from University College London and the UK’s Natural History Museum published in Current Biology shows that the region where fewer fossils were found is the area closest to the Ecuador. Until now it was believed that, because there were not so many records, there were no dinosaurs in that location.
But researchers believe this is not necessarily true, explains .
“Paleontological expeditions to these regions may be less common due to the harshness of the Sahara environment and the inaccessibility of many areas of the Amazon”, the authors.
“It is also well documented that factors socioeconomic and the legacy of colonialismtogether with the political instabilityprobably hampered research efforts in these regions”, they comment.
There may then only be a region with missing fossils, rather than a region without dinosaurs.
Based on proposed evolutionary trees, scientists modeled scenarios, with the most supported being a low-latitude Gondwanan origin. This hypothesis could mean that the evidence could be in the Sahara Desert and the Amazon.
This is only in a model in which the silesauridswhich are often seen as “cousins” of dinosaurs) consider themselves ancestors of dinosaurs ornithísquios (one of the groups missing from the fossil record of the first dinosaurs).
“Until now, no dinosaur fossils have been found in the regions of Africa and South America that formed this part of Gondwana,” say the authors.
“However, this may be due to the fact that researchers haven’t found the right rocks yetdue to a mixture of inaccessibility and a relative lack of research efforts in these areas.”
