INGV and Sapienza University researchers discover dinosaurs’ footprints in Abruzzo
A team of researchers of the National Institute of Geophysics and Volcanology (INGV) and icnologists of the Sapienza University of Rome have discovered dinosaurs’ footprints, between 125 and 113 million years old, which show the presence of the largest theropod ever documented in Italy.
The results of this finding, published in Cretaceous Research (Elsevier), provide additional information on the animals that lived on the Italian shores in Cretaceous and their behaviour, thus increasing the collection of dinosaur footprints in Italy that, being under investigation for decades in Italy and still being updated today, have allowed to revolutionize the assumptions on the geography of the Mediterranean area in the Mesozoic (between 200 and 65 million years ago).
“The tracks”, said Fabio Speranza, an INGV researcher, “are located at a height of over 1,900 m on an almost vertical limestone surface on the side of Monte Cagno. The area can only be reached (when the mountain is not covered in snow, during the summer and autumn months) after a two-hour hike from the nearest town, Rocca di Cambio, near L’Aquila. Among the tracks, one footprint was found, measuring 135cm in length, that is the largest which has ever been found in Italy.
Most of these tracks were left by one or more therpods that sank in the muddy ground, while others, at the centre of the limestone surface, were left by a crouching animal.
Theropods are a group of saurischian dinosaurs, one of the two big divisions of dinosaurs (the other being ornithischian dinosaurs). They were bipedal, mainly carnivorous, although a number of theropod groups evolved herbivory, omnivory, piscivory, and insectivory. Theropods first appeared during the late Triassic period and included the only included the only terrestrial carnivores of large size about 66 million years ago, from the Lower Jurassic to the end Cretaceous.
“The track, accidentally discovered in the summer 2006”, continued Speranza, “were found on a limestone surface dating back to the Lower Cretaceous and reminded of dinosaur footprints. But only in the summer 2015, thanks to technological developments and collaborations with footprint experts from the Sapienza University, was it possible to give a new impulse to investigations. The researchers used a camera drone and an innovative technique of digital photogrammetry to reconstruct an accurate 3D model from simple photo images. Thanks to this technique, inspired by the movie setting (used in “Jurassic Park”, 1993) it was possible to study the footsteps of the vertical surface in detail, taking them to a virtual environment that could be easily analyzed with the computer. For a more precise dating, we obtained samples of the footsteps and of the layers just above and below them”.
“Contrary to what was believed in the past” said Paolo Citton from the Sapienza University of Rome, “the tracks show repeated migration of dinosaurs from the Gondwana continent (which joined Africa, South America, Antarctica, India and Australia) to the carbonate platforms of the Mediterranean (an environment similar to todays’ Bahamas). As stated before by icnoogists of the Sapienza University, this movement was made possible by variations in sea level, processes on a global scale which took place over long time periods on our planet.”
“The new footprints”, conclude Citton, “could show to be particularly precious for the additional information on the composition of the dinosaur fauna in Italy, with an important impact on ecology and on the routes followed by these extinct animals”.