About 65 million years ago, a killer asteroid wiped out life on Earth. Everything from giant marine reptiles, dinosaurs, mammals and other animals to microscopic organisms became extinct except for deep sea creatures, but how did they manage to survive?
Scientists at Cardiff University has found new evidence to shed light on why deep sea creatures had survived from what is dubbed as one of the most widespread mass extinction events in the history of the planet.
This asteroid, about as big as England's Isle of Wight, struck the Mexican Yucatan peninsula, triggering gigantic tsunamis, big killer earthquakes and landslides across the globe.
The survival of these deep sea creatures has puzzled scientists throughout history since many believe that the impact of the asteroid could have stopped food supply in the oceans, killing free-floating organisms like bacteria and algae. If the ecosystems in the waters are altered, this could have led to death of sea creatures as well.
Fortunately for these creatures, they survived.
The new study analyzed data from fossilized shells and their chemical composition that were dated back from the period when the mass extinction happened. The results show that some forms of bacteria and algae survived, sunk and served as food for deep sea creatures after the disaster.
By about 1.7 million years after the disaster, ocean food supply has fully recovered, the calculations of the experts showed.
"Our results show that despite a wave of massive and virtually instantaneous extinctions among the plankton, some types of photosynthesizing organisms, such as algae and bacteria, were living in the aftermath of the asteroid strike," said Heather Birch, from Cardiff University and co-author of the study.
Despite taking nearly 2 million years for the food supply to bounce back, the creatures' survival instinct has paved way to the evolution of species to occupy the vacated extinct ones.
The findings of the study, which was published in the journal Geology, may finally answer a long-time puzzling question among scientists.
Photo: Mark Waters | Flickr
