A research team has uncovered the first fossil-record evidence of forest fire ecology that happened towards the end of the Cretaceous Period, about 66 million years ago in southern Saskatchewan.
The new discovery has made crucial revelations about the ecology and climate on the Earth just before the mass extinction of the dinosaurs.
The findings were made during an expedition in southern Saskatchewan, Canada led by a joint research team from McGill University and the Royal Saskatchewan Museum.
“Excavating plant fossils preserved in rocks deposited during the last days of the dinosaurs, we found some preserved with abundant fossilized charcoal and others without it. From this, we were able to reconstruct what the Cretaceous forests looked like with and without fire disturbance,” said Hans Larsson, Canada Research Chair in Macroevolution at McGill University.
The study revealed that the ancient forests also recovered in the similar way as it happened today, with plants like alder, birch, and sassafras present in early stages, and sequoia and ginkgo present in mature forests.
Lead author Emily Bamforth, of the Royal Saskatchewan Museum, said, “We were looking at the direct result of a 66-million-year old forest fire, preserved in stone. Moreover, we now have evidence that the mean annual temperature in southern Saskatchewan was 10-12 degrees Celsius warmer than today, with almost six times as much precipitation”.
Another researcherLarsson, who is also an Associate Professor at the Redpath Museum, said, “The abundant plant fossils also allowed us for the first time to estimate climate conditions for the closing period of the dinosaurs in southwestern Canada, and provides one more clue to reveal what the ecology was like just before they went extinct.”
Key findings of the study
- The region was 10-12 degrees Celsius warmer than it is in the present day.
- The amount of rain was about six times its current rate.
- The rocks that were uncovered indicate that the climate of Canada during the Cretaceous was much wetter and hotter than the present day.
- Fossilized flora from the prehistoric wreckage were found that were similar to the plants that grow following modern day forest fires.
- The study can serve as a connecting link between the present day Earth and the planet just before the dinosaurs died out.
- It may be helpful for the researchers who want to understand the evolution of pyrophilic plants – plants that are dependent on and benefit from fires to promote growth.