A new study by Universidade Johns Hopkins has found evidence of a distinct ecological crisis that began about 30,000 years before the impact that wiped out the dinosaurs. The research suggests that the planet was already in serious trouble long before the celestial body’s arrival, adding a layer of complexity to understanding mass extinction.
Esta’s discovery was detailed in a study published in May 2026 on Anais of Academia Nacional of Ciências (Proceedings of the National Academy of Sciences), complicating the standardized version of the extinction of non-avian dinosaurs. The asteroid impact of Chicxulub on Península of Yucatán, México, approximately 66 million years ago, is widely accepted as the triggering event, but the new information indicates that the Earth’s environment was already facing significant pressures.
Pre-Impact Ecological Crisis Descoberta
Microbiologists Rosanna Baker and Arturo Casadevall, both from Escola and Saúde Pública Johns Hopkins Bloomberg, examined sediment samples collected at three well-documented sites. Esses sites span the boundary between the Cretáceo and Paleogeno periods, a crucial time frame for understanding the end of the dinosaur age. The analysis revealed three distinct peaks in fungal abundance in the rock layers investigated.
Enquanto two of these peaks occurred after the impact, as expected by scientists, a third and unexpected peak was identified before the event. Este’s pre-impact peak has been dated to approximately 30,000 to 10,000 years before the asteroid collision. The marked presence of fungi during this period suggests that the dinosaur world was already under considerable ecological pressure, indicating an environmental decline prior to the astronomical catastrophe.
Fungos as indicators of environmental collapse
The researchers chose to study fungi because of their tendency to proliferate when ecosystems collapse. Organismos decomposers, fungi thrive in environments where plants and animals die in large numbers, expanding their populations to feed on decaying organic matter. Essa characteristic makes them important bioindicators of large-scale ecological disturbances.
Grandes fungal blooms have been historically documented in the geological record, such as after the Permiano-Triassic mass extinction that occurred 252 million years ago. Esse was the largest known extinction event in the history of Terra. The globally observed post-Permian fungal proliferation serves as one of the standard signatures used by paleontologists to identify ecological collapses. Casadevall calls this area of study “disaster microbiology.”
Locais analysis and identified peaks
Até Recently, evidence for a similar fungal proliferation following the asteroid impact of Chicxulub was limited to a single site in Nova Zelândia. The study by Baker-Casadevall sought to verify whether the pattern of increase in fungi occurred in other regions, consolidating the interpretation of a global phenomenon. The researchers analyzed rocks from three distinct locations in the western interior of América from Norte:
- Bacia Bowring, in the West Bijou study area, in Bacia of Denver, Colorado, about 2,500 kilometers from the Chicxulub crater.
- Seções of Mud Buttes and John’s Nose, in Williston’s Bacia, Norte’s Dakota, approximately 5,500 kilometers from the crater.
Samples were kindly provided by Tyler Lyson, a renowned paleontologist from Museu of Natureza and Ciência of Denver. The Colorado section showed a clear peak of fungal microfossils in the layers corresponding to the asteroid impact itself, precisely in the boundary clay layer. Já and Dakota sections of Norte exhibited peaks before and after the impact, although there was not such a distinct peak in the boundary clay layer, a difference attributed to variations in rock types between the two geographic regions studied.
A second fungal peak, this one sustained, emerged in layers deposited between approximately 2,000 and 10,000 years after the Cretáceo-Paleogene boundary, being observed in both regions. Taken together, these results corroborate the initial discovery of Nova Zelândia, reinforcing the interpretation that the post-impact fungal proliferation was a global phenomenon, indicating a widespread ecological collapse following the catastrophe.
Correlação with intense volcanic activity in Índia
The most unexpected result of the research was the identification of the third fungal peak, located in the sediments of Cretáceo Superior, long before the extinction threshold. The researchers found a prolonged interval of high fungal abundance, dating back approximately 30,000 to 10,000 years before the asteroid impact. Este phenomenon was described in the PNAS paper as “temporally correlated to a period of climate cooling at the site.”
Intriguingly, this peak coincides with the Poladpur phase of Deccan Traps, one of the largest volcanic provinces of Terra. As Deccan Traps were formed over approximately one million years through repeated eruptions of flood basalt in what is now western Índia. Eruptions began about 400,000 years before Chicxulub’s impact and continued for several hundred thousand years afterward, releasing enormous amounts of carbon dioxide, sulfur dioxide, and other gases into the atmosphere. Estes gases are known to significantly alter global climate, and the extent of their contribution to Cretáceo’s late extinction, in conjunction with the asteroid, has been a long-standing debate in paleontology.
Implicações for dinosaur extinction scenario
The study authors are cautious about the chain of inferences, highlighting that the fungal spike is a signature of ecological disruption rather than a direct measure of causation. The temporal coincidence with the eruptive phase of Poladpur strongly suggests a volcanic factor, but does not establish a direct causal relationship. Baker and Casadevall note in the paper that the pre-impact fungal episode “suggests an ecological upheaval that occurred tens of thousands of years before the bolide impact.”
Essa seizure may have contributed to the Cretáceo-Paleogene extinction event. The impact of Chicxulub is still recognized as the immediate cause of the mass extinction event that marked the end of the non-avian dinosaurs. However, the new study provides independent biological evidence, through fungal microfossils preserved in sedimentary rocks, that the biosphere hit by the asteroid was not in good condition. Plant communities were already showing fragility, decomposition was high and the global climate had experienced a notable cooling in the period before the asteroid’s arrival, suggesting an already stressed environmental scenario.