A new species of giant dinosaur discovered during construction work in northeastern Brazil offers new insights into how sauropods spread across the ancient continents.
The species has been named Dasosaurus tocantinensis and is described in a study published in the Journal of Systematic Paleontology. The animal was about 20 meters long and lived approximately 120 million years ago. Its fossils were found at a road-and-rail terminal construction site in Davinópolis, in the state of Maranhão.
ΣΧΕΤΙΚΑ ΑΡΘΡΑ
From Europe to South America
Of particular interest is its evolutionary relationship to a dinosaur that lived in what is now Spain. This suggests that the two belonged to a broader evolutionary lineage that once spanned regions now separated by the Atlantic Ocean, according to Science Daily.
Researchers estimate that the ancestors of Dasosaurus tocantinensis reached South America via North Africa between 140 and 120 million years ago. At that time, these landmasses were still connected as part of the supercontinent Gondwana.
The new dinosaur is the largest one discovered to date in the state of Maranhão. Other species have been found in the region, but they were smaller, such as Amazonsaurus maranhensis, a sauropod about 10 meters long.
The discovery of the bones
The bones were uncovered by archaeologists monitoring the work as part of environmental permitting requirements. They were initially thought to belong to large prehistoric mammals. However, Elver Luiz Mayer, a professor at the Federal University of the São Francisco Valley, suspected they were much older.
The depth at which they were found—about eight meters—and the known age of the geological formation indicated that the fossils dated back to the Cretaceous period, approximately 120 million years ago. An interdisciplinary team was subsequently formed to study them.
The specimen proved to be unusually complete. Among other things, it includes tail vertebrae, ribs, limb and foot bones, as well as a 1.5-meter-long femur. Paleontologists believe that even more bones from the same animal may be found at the same site.
The species’ name refers both to the landscape of Maranhão and to the region’s geography. “Daso” comes from the Greek word “dásos,” a reference to the dense forest vegetation, while “tocantinensis” comes from the Tocantins River, as the fossils were found near its eastern bank.
What We Learn from the Discovery
Scientists also studied the microscopic structure of the bones. The analysis revealed a growth pattern that combines characteristics of earlier sauropods with features of titanosaurs, a group related to the new species. The findings suggest that certain mechanisms of bone growth and remodeling appeared earlier in dinosaur evolution than previously thought, which may help explain how certain sauropods reached such enormous sizes.
The discovery also highlights the dual role of large-scale construction projects in paleontology. On the one hand, they can destroy fossil-bearing layers; on the other hand, however, they expose rocks that often remain hidden beneath vegetation or the ground. Researchers therefore emphasize the need for closer collaboration between construction companies and scientific institutions, so that projects can proceed without losing valuable paleontological heritage.
Source: Cnn.gr
