A time-averaged artists analysis of Patagonia throughout the Late Cretaceous. The animals visualized consist of non-avian dinosaurs, birds and other vertebrates that have actually been found in the fossil record of the region. Their specific recognitions are as follows: ornithurine birds (flying and walking on the ground), Stegouros (armored dinosaur), Orretherium (mammal), Yaminuechelys (turtle), a megaraptorid (big carnivore), unenlagiines (pair of carnivores), and enantiornithine birds (in foreground). Credit: Mauricio Alvarez and Gabriel Diaz
A study led by The University of Texas at Austin is offering a look into dinosaur and bird variety in Patagonia throughout the Late Cretaceous, prior to the non-avian dinosaurs went extinct.
The fossils represent the first record of theropods– a dinosaur group that consists of both contemporary birds and their closest non-avian dinosaur relatives– from the Chilean portion of Patagonia. The researchers finds consist of huge megaraptors with big sickle-like claws and birds from the group that likewise includes todays contemporary species.
” The animals of Patagonia leading up to the mass termination was actually varied,” stated lead author Sarah Davis, who completed this work as part of her doctoral studies with Professor Julia Clarke at the UT Jackson School of Geosciences Department of Geological Sciences. “Youve got your large theropod carnivores and smaller predators along with these bird groups existing together along with other reptiles and little mammals.”
The research study was released recently in the Journal of South American Earth Sciences.
A figure from the research study revealing teeth from a megaraptor dinosaur from different view points. The black tooth preserves the majority of the tooth crow. The tan tooth is missing the crown pinnacle and base. Credit: Davis et al
. Since 2017, members of the Clarke lab, including graduate and undergraduate trainees, have joined clinical partners from Chile in Patagonia to gather fossils and develop a record of ancient life from the area. Over the years, researchers have actually found abundant plant and animal fossils from prior to the asteroid strike that exterminated the dinosaurs.
The research study focuses particularly on theropods, with the fossils dating from 66 to 75 million years back.
Non-avian theropod dinosaurs were primarily meat-eating, and consist of the leading predators in the food chain. This study reveals that in prehistoric Patagonia, these predators included dinosaurs from 2 groups– unenlagiines and megaraptors.
Reaching over 25 feet long, megaraptors were amongst the larger theropod dinosaurs in South America during the Late Cretaceous. The unenlagiines– a group with members that ranged from chicken-sized to over 10 feet tall– were most likely covered with plumes, similar to their close relative the velociraptor. The unenlagiinae fossils explained in the research study are the southernmost known instance of this dinosaur group.
The scientists in Patagonia in 2017. Lead author Sarah Davis remains in the center of the front row in a blue coat. The researchers include members from the Jackson School of Geosciences, INACH, the University of Chile, and the University of Concepción. Credit: Sarah Davis
The bird fossils were also from 2 groups– enantiornithines and ornithurines. Now extinct, enantiornithines were the most abundant and diverse birds millions of years ago. These resembled sparrows– but with beaks lined with teeth. The group ornithurae consists of all contemporary birds living today. The ones residing in ancient Patagonia may have resembled a goose or duck, though the fossils are too fragmentary to tell for sure.
The scientists determined the theropods from little fossil fragments; the dinosaurs mainly from toes and teeth, the birds from small bone pieces. Davis said that the enamel glinting on the dinosaur teeth aided with spotting them amongst the rocky terrain.
Some scientists have suggested that the Southern Hemisphere dealt with less severe or more progressive climatic modifications than the Northern Hemisphere after the asteroid strike. This might have made Patagonia, and other locations in the Southern Hemisphere, a sanctuary for birds and mammals and other life that endured the extinction. Davis said that this research study can help in examining this theory by developing a record of ancient life before and after the extinction event.
Research study co-author Marcelo Leppe, the director of the Antarctic Institute of Chile, said that these previous records are key to comprehending life as it exists today.
” We still need to understand how life made its way in that apocalyptic circumstance and gave increase to our southern environments in South America, New Zealand and Australia,” he said. “Here theropods are still present– no longer as dinosaurs as enforcing as megaraptorids– but as the varied array of birds found in the forests, swamps and marshes of Patagonia, and in Antarctica and Australia.”
Recommendation: “New records of Theropoda from a Late Cretaceous (Campanian-Maastrichtian) region in the Magallanes-Austral Basin, Patagonia, and insights into end Cretaceous theropod variety” by Sarah N. Davis, Sergio Soto-Acuña, Roy A. Fernández, Jared Amudeo-Plaza, Marcelo A. Leppe, David Rubilar-Rogers, Alexander O. Vargas and Julia A. Clarke, 17 December 2022, Journal of South American Earth Sciences.DOI: 10.1016/ j.jsames.2022.104163.
The research was funded by the National Science Foundation, the National Agency for Research and Development of Chile, and the Jackson School of Geosciences.
The studys co-authors consist of Clarke and researchers at the University of Chile, Major University, the University of Concepción and the Chilean National Museum of Natural History.
The animals imagined consist of non-avian dinosaurs, birds and other vertebrates that have been found in the fossil record of the area. Their specific identifications are as follows: ornithurine birds (walking and flying on the ground), Stegouros (armored dinosaur), Orretherium (mammal), Yaminuechelys (turtle), a megaraptorid (big carnivore), unenlagiines (pair of predators), and enantiornithine birds (in foreground). The bird fossils were likewise from 2 groups– ornithurines and enantiornithines. Now extinct, enantiornithines were the most diverse and abundant birds millions of years ago. The group ornithurae includes all modern-day birds living today.
