New Research Questions Hypotheses of Climate-Controlled Ecosystem Change During the Origin of Dinosaurs in Argentina – Do You Stand Out for That?
UNIVERSITY OF UTAH
CREDIT: JORGE GONZALEZ / UTAH’s NATURAL HISTORY MUSEUM
A team of researchers from CONICET and the University of Utah have demonstrated that during the time of the early dinosaurs, variations in the diversity and abundance of vertebrates could not be related to each other. Climate changes were recorded during its deposition, contrary to previous hypotheses.
In the new researchpublished in an open access journal Frontiers in Earth Science, the team of scientists investigated multiple independent lines of evidence (sedimentation, clay mineralogy, and geochemistry) to elucidate changes in paleontological conditions (such as mean precipitation annual and mean annual temperature) in the Ischigualasto Formation. These fossil-rich sedimentary rocks were deposited by rivers and streams between 231 and 226 million years ago during the Late Triassic in what is now northwestern Argentina (La Rioja and San Juan provinces). Midway through the formation, the researchers observed a clear change in conditions from warmer, drier to more temperate humid conditions, but no large simultaneous changes could be observed. identified in the fossil record.
“We conclude that variations in species richness and diversity, are recorded by their first and last occurrences in the chemical record,” said Adriana Mancuso, lead author and CONICET. fossils, are better explained by preservation and sampling biases than by climate change. independent researcher at the Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales in Mendoza, Argentina.
“What we saw was how many specimens were collected from each time period of the sequencing, and the chemical and physical characteristics allowed for more or less preservation of animal and plant remains. , are important factors. Two factors, collection and preservation, have more influence on increases or decreases in abundance and diversity than recorded climate changes,” explains Mancuso.
However, although ecosystem evolution did not generally show biological responses related to climate change, the team observed a relationship between climate variations and the two groups of cows. reptiles, herbivorous archosauromorphs and pseudosuchians (crocodilian archosaurs). Randall Irmis, co-author from the U and Utah Museum of Natural History, said: “We found that the abundance of monkeys and the extinction of some pseudosuchian species appear to coincide with the the climate changes.
In addition to concluding this particular fossil and paleontological record from Argentina, the new study highlights the importance of a clear framework for testing hypotheses about the link between climate changes and lakes. fossil record. “In addition to its contribution to the relationship of climatological and biotic events in the Ischigualasto Formation, the work provides a methodological framework for examining bioclimate linkages, highlighting the intervals data gaps need to be filled and new predictions are testable. in future studies,” Mancuso concludes.
Other authors include Tomás Pedernera and Cecilia Benavente of the Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (CONICET), Leandro Gaetano from the Instituto de Estudios Andinos (CONICET) and Departamento de Ciencias Geológicas of the University of Buenos Aires, Breeden. University of Utah.
JOURNEYS
Frontiers in Earth Science
DOI
RESEARCH METHODS
Observational research
RESEARCH SUBJECTS
Do not apply
ARTICLE TITLE
Environmental and paleontological changes during the late Triassic of Argentina: testing hypotheses of abiotic compulsion at the basin scale.
ARTICLE PUBLICATION DATE
June 13, 2022
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