Although scientists previously believed that creatures residing in the southernmost regions of the Earth were likely not as affected by the mass extinction event that wiped out the dinosaurs, a new study of more than 6,000 marine fossils from the Antarctic suggests otherwise.
The new research stems from a six-year period of identifying these marine fossils, which were 69 to 65 million years old. The remains were obtained from Seymour Island, located in the Antarctic Peninsula.
Led by researchers from the University of Leeds and the British Antarctic Survey, the study examines one of the largest collections of marine fossils of our time. This collection contains a wide variety of species, from smaller snails and clams to massive underwater creatures.
The results suggest a 65 to 70 percent reduction in the number of species living in the Antarctic approximately 66 million years ago at the end of the Cretaceous period - the same time that dinosaurs and various other organisms were wiped out.
"Our research essentially shows that one day everything was fine - the Antarctic had a thriving and diverse marine community - and the next, it wasn't," said James Witts of the University of Leeds and lead author of the paper. "Clearly, a very sudden and catastrophic event had occurred on Earth."
"This is the strongest evidence from fossils that the main driver of this extinction event was the after-effects of a huge asteroid impact, rather than a slower decline caused by natural changes to the climate or by severe volcanism stressing global environments," he added.
Prior to the current research, scientists believed that organisms near the poles were likely safe from the extinction event. In addition, they suggested that these organisms would be less susceptible to the pitfalls of global climate change due to their strongly seasonal environments.
"These Antarctic rocks contain a truly exceptional assemblage of fossils that have yielded new and surprising information about the evolution of life 66 million years ago," said Jane Francis from the British Antarctic Survey and co-author of the study. "Even the animals that lived at the ends of the Earth close to the South Pole were not safe from the devastating effects of the mass extinction at the end of the Cretaceous Period."
The findings were published in the May 26 issue of Nature Communications.
