A team of researchers has tried to assess how long it took for life on Earth to recover from the mass extinction some 66 million years ago, believed to have been caused by an asteroid. The results show that it took at least 2 million years to restore the level of plankton, an essential element of the entire ocean ecosystem. After the impact of the asteroid, plankton, especially the smaller one, nanoplankton, was almost completely destroyed.
These creatures are important because once they die, they throw their calcium and carbon exoskeletons onto the seabed. At the bottom of the sea, they form rich organic deposits that thicken and become lime. And it is by analyzing the fossil layers of these deposits that researchers have obtained data on plankton.
Analyzing various other fossil data, the researchers found that it took at least another 8 million years for the number of species of living creatures to return to their previous levels, i.e., the level preceding the catastrophic event.
Researchers described their findings in an article in the Conversation (below).
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