The fossilization process of the dinosaur remains

May 06, 2019

The site or bone bed at La Cantalera-1 is located in Teruel (Spain) and regarded as hugely important by the scientific community as it is one of the sites on the Iberian Peninsula with the greatest diversity of vertebrates of the Lower Cretaceous. Remains of dinosaurs, mammals, crocodiles, pterosaurs, lizards, tortoises, amphibians and fish dating back to approximately 130 million years ago have been discovered. A multidisciplinary piece of research carried out by researchers in the Department of Stratigraphy and Palaeontology and the Department of Mineralogy and Petrology at the UPV/EHU's Faculty of Science and Technology, together with the University of Zaragoza (Aragosaurus-IUCA Group), has explored not only the fossilization process (taphonomy) which took place in some of these remains, but also the internal structure displayed by the bones (palaeohistology).

Although given its importance, the site has undergone thorough investigation, "no previous investigation had tackled it from these perspectives or with the depth that we have conducted in this study", pointed out Leire Perales-Gogenola, a member of the UPV/EHU's Department of Stratigraphy and Palaeontology and lead author of the paper.

For their work they selected two groups of dinosaurs: ornithopods (of which there are abundant remains at the site), and ankylosaurs (known as armoured dinosaurs as they had armour consisting of bony plates). Although large fossil items exist, this research group resorted to "fragmentary remains, small pieces of bone and the dermal bones. The methodology we had to follow involved making sections in the samples and we did not want to damage the more important items," stressed the researcher.

Wetland ecosystem with a wealth of young individuals

The part of the study of the internal structures of the fossil bones (palaeohistology) "revealed that most of the ornithopod dinosaurs were young individuals. On inspecting the fossilized bones under the microscope, they were found to display the same structure as unfossilized bones as they retain all their characteristics. This enables us to identify the signs that tell us whether they belonged to adult or immature individuals; it is possible to know, for example, whether the individual in question was a large but young dinosaur or whether it was a small but adult dinosaur", explained the UPV/EHU biologist and palaeontologist. In the study of the internal part of the dermal bones they observed "various traces that other researchers had associated with a specific group of ankylosaurs, so in some cases we were able to determine more accurately what kind of dinosaurs they were".

For the taphonomic study the researcher stresses the usefulness in having analysed fragmentary remains, "as they are bones that have undergone fractures owing to the pressure of the subsequent burial itself, among other things, and this has allowed various sedimentary materials to filter through these fractures, which have been fossilized beside the bone remains; this provides hugely valuable information about the environment in which they were found". In this part of the study they were able to deduce that these bones were subjected to rapid burial and soon reached the phreatic level in which the fossilization processes had already taken place. Microbial activity in the bones, the presence of bacterial forming microbial carpets, has also been detected, and this may have encouraged the fossilization process.

The results obtained have helped to increase the available knowledge about the site and basically "the features of the ecosystem and degree of maturity of the individuals present, which had already been described in previous studies, have been confirmed. The data indicate that it was a wetland ecosystem and was used as a feeding zone for the fauna in the area. Due to the wealth of young individuals and eggshell remains, which are also very abundant at the site, it has been suggested that it could have been a breeding or feeding area", said Perales-Gogenola.

Forthcoming studies at the site anticipated by the University of Zaragoza are due to tackle the palaeohistology of the dinosaurs present at La Cantalera-1 and also to go further into the age of death of the herbivore dinosaurs, to certify whether it was a natural population or whether there is an excessive number of youngsters owing to predation issues by theropod dinosaurs (carnivorous dinosaurs that could attack young individuals more frequently than adult individuals).
-end-
Bibliographical reference

Leire Perales-Gogenola, Javier Elorza, José Ignacio Canudo, Xabier Pereda-Suberbiola
Taphonomy and palaeohistology of ornithischian dinosaur remains from the Lower
Cretaceous bonebed of La Cantalera (Teruel, Spain)
Cretaceous Research (2019)
DOI: 10.1016/j.cretres.2019.01.024

University of the Basque Country

Related Dinosaurs Articles from Brightsurf:

Ireland's only dinosaurs discovered in antrim
The only dinosaur bones ever found on the island of Ireland have been formally confirmed for the first time by a team of experts from the University of Portsmouth and Queen's University Belfast, led by Dr Mike Simms, a curator and palaeontologist at National Museums NI.

Baby dinosaurs were 'little adults'
Paleontologists at the University of Bonn (Germany) have described for the first time an almost complete skeleton of a juvenile Plateosaurus and discovered that it looked very similar to its parents even at a young age.

Bat-winged dinosaurs that could glide
Despite having bat-like wings, two small dinosaurs, Yi and Ambopteryx, struggled to fly, only managing to glide clumsily between the trees where they lived, according to a new study led by an international team of researchers, including McGill University Professor Hans Larsson.

Some dinosaurs could fly before they were birds
New research using the most comprehensive study of feathered dinosaurs and early birds has revised the evolutionary relationships of dinosaurs at the origin of birds.

Tracking Australia's gigantic carnivorous dinosaurs
North America had the T. rex, South America had the Giganotosaurus and Africa the Spinosaurus - now evidence shows Australia had gigantic predatory dinosaurs.

Ancient crocodiles walked on two legs like dinosaurs
An international research team has been stunned to discover that some species of ancient crocodiles walked on their two hind legs like dinosaurs and measured over three metres in length.

Finding a genus home for Alaska's dinosaurs
A re-analysis of dinosaur skulls from northern Alaska suggests they belong to a genus Edmontosaurus, and not to the genus recently proposed by scientists in 2015.

Can we really tell male and female dinosaurs apart?
Scientists worldwide have long debated our ability to identify male and female dinosaurs.

In death of dinosaurs, it was all about the asteroid -- not volcanoes
Volcanic activity did not play a direct role in the mass extinction event that killed the dinosaurs, according to an international, Yale-led team of researchers.

Discriminating diets of meat-eating dinosaurs
A big problem with dinosaurs is that there seem to be too many meat-eaters.

Read More: Dinosaurs News and Dinosaurs Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.