Plaster Group
Garumbatitan morellensis, sauropod dinosaur discovered in Spain
Although sauropods are the largest land animals in Earth’s history, their young take a long time to grow, which leaves them vulnerable to predators.
A new study led by a researcher at University College London (UCL) suggests that baby sauropod dinosaurs and juveniles played a crucial role in sustaining large predators during the Late Jurassic period, about 150 million years ago.
Although adult sauropods became the largest land animals in Earth’s history, their early life stages were small, defenseless, and highly vulnerable, making them a vital food source in predator-rich ecosystems.
The investigation, in the New Mexico Museum of Natural History and Science Bulletin, is based on fossil evidence from the Morrison Formation in the western United States. Using these fossils, scientists reconstructed a Jurassic food web specifically, mapping the feeding relationships between plants, herbivores and carnivores with a level of accuracy exceptional for dinosaur ecosystems.
According to the study, juvenile sauropods were regular prey of carnivorous dinosaurs, such as Allosaurus and Torvosaurus. Unlike heavily blind herbivores like Stegosaurus, young sauropods lacked physical defenses and apparently received little or no parental care. Their small size and isolation made them easy targets for predators.
While Diplodocus and Brachiosaurus, as adults, could rival or even surpass the length of a blue whale, their eggs were only about 30 centimeters in diameterand the offspring took many years to reach imposing sizes. Physical evidence suggests that adults were unable to robustly protect the nests, leaving the young exposed. As a result, predator populations were largely supported by feeding on these vulnerable juveniles, explains the .
Much of the data came from Dry Mesa in Colorado, one of the richest Late Jurassic fossil sites known. The quarry preserves remains of at least six species of sauropodsaccumulated over thousands of years. Researchers combined evidence such as body size, damaged wear, chemical isotope analysis and rare fossilized stomach contents to determine relationships between predators and prey.
Using software typically applied to modern ecosystems, the team reconstructed a comprehensive Jurassic food web. An analysis revealed that sauropods occupied a central positionattaching itself to more plant species and predators than any other group of herbivorous dinosaurs.
