Spanish researchers connect dinosaur mass extinctions to Jenkyns Event

According to the Spanish Journal of Paleontology, the dinosaur extinction was related to the Jenkyns Event, a global event that depleted the world of oxygen.

During the early Toarcian Period, which occurred approximately 183 million years ago, the Jenkyns Event took place. This cataclysm, which was caused by volcanic activity from the Karoo-Ferrar Large Igneous Province, had the effect of causing significant changes to terrestrial ecosystems, including the extinction of certain species of dinosaurs. 

The occurrence was characterized by a disturbance in the global carbon cycle, which led to increased global warming, intensified chemical weathering, enhanced soil erosion and an increase in the number of wildfires. These changes also affected the assemblages of land plants, which resulted in the destruction of forests and had an effect on trophic webs.

The Jenkyns Event caused significant shifts in the structure and function of terrestrial ecosystems. Fossil records of plant communities and palynological data show reductions in the diversity and richness of plant communities, along with a significant loss of land plant biomass and a shift toward forests dominated by Cheiropelidiaceae conifers. 

This loss of land plant biomass was accompanied by a shift in vegetation type from grasslands to forests. Both herbivorous and carnivorous dinosaur populations were significantly influenced by the event. In the end, the extinction of numerous basal families of Sauropodomorpha (also known as "prosauropods") and some basal sauropods was caused by the loss of forests, which affected the diversity and composition of land plant assemblages. 

This, in turn, led to changes in trophic webs, which led to changes in trophic levels. The Jenkyns Event was also responsible for the extinction of the most successful group of carnivorous dinosaurs, the Coelophysoidea (Theropoda).

The Jenkyns Event is recognized as a crisis for terrestrial ecosystems, as it caused significant flora shifts as well as the extinction of several dinosaur clades, including those that were herbivorous and carnivorous. Both global warming and acid rain had a significant influence on the diversity and composition of land plant assemblages, which resulted in the destruction of forests and had an effect on food webs. 

This event highlights how important it is to understand how geological events can shape the evolution of life on Earth, and also provides insights into the vulnerability of ecosystems in the face of changes in their surrounding environments.