Some 65 million years ago, an asteroid hit only six miles wide the planet. The resulting dust shoot and dirt that penetrated the atmosphere blocked sunlight for several weeks, while earthquakes, landslides and tsunamis were destroyed by what is now America.
When all was said and done, Tyrannosaurus Rex and its Saurichian compatriots were all dead along with 75% of the plan's species.
Today, another force is driving the earth against its next extermination event. Human changes in the planet hit global species on multiple fronts, as warmer oceans, deforestation, and climate change drive flower and fauna populations to extinction in unprecedented numbers. As much as half of the total number of individuals who once shared the Earth with humans is already gone, a clear sign that we are on the verge, if not in the middle of it, a sixth mass extinction.
Read more: 1
A new study published in the journal Nature Ecology and Evolution reveals that it took the planet about 10 million years to recover from mass extinction, who wiped out the dinosaurs.
That's bad news if we want to get the Earth's current dipping biodiversity back on track.
"From this study it is reasonable to conclude that it will take an extremely long time – millions of years – to recover from the extinction we cause through climate change and Other methods, "co-authored the new study Andrew Fraass said in a press release.
As we continue to involve animal habitats, pollute their ecosystems, and drive the earth toward warmer and warmer temperatures, we march stubbornly away from a version of the world that we will never be able to return.
"Biodiversity loss will not be replaced for millions of years, and so when imagining extinctions in coral reefs ecosystems, or rainforest ecosystems, or grassland, or anywhere, these sites will be less diverse essentially for ever as far as as people worry, "said Chris Lowery, palaeobiologist and co-author of the new study, Business Insider.
An Evolutionary "Speed Limit"
Scientists have long argued that the 10 million-year global biodiversity timeframe for proper rebound is a feature of all five Earth's mass extinctions, but for the first time, there is now fossil evidence for this delay. .
To determine how quickly Earth's biodiversity was restored after the mass extinction event 65 million years ago, Lowery and Fraass examined small single cell organisms called planktic foraminifera, which are abundant in the fossil plate (there are about 4,000 species still alive today , according to the University of California Museum of Paleontology in Berkeley).
The paleo biologists looked at how foraminifera biodiversity changed in the fossil record from before the extinction event to after, and how long it took for the organism's level of biodiversity to return to pre-asteroid levels after the disaster.
In an ecosystem, each animal and plant species possesses a unique niche – the specific part of an ecosystem in which an organism is located. A mass disappearance of species one might think that these niches would still be available to adaptable survivors to then take over. But, according to Lowery, this is not the case.
"Niches and organisms that fill them are basically inseparable, so a mass destruction destroys niches as it destroys species," he said. The new study shows that these complex organic niches must be rebuilt before the species's diversity can be fully restored, and that is the reason for the delay.
The authors discovered that the surviving foraminifera species became more complex (and thus capable of creating and filling new niches) before they diversified, suggesting ecological complexity prior to diversification.
"What is interesting is that there seems to be a hard speed limit for this process and it is about 10 million years to complete, "Lowery added.
The authors of the study wrote that the generation of new ecological niches after a mass extinction means that the world that rebuilt after the asteroid strike was a "brand new" ecosystem, "rather than a return to a mirror version" of how the world was as before the extermination
"This should serve as an important reminder: some organic niches lost due to man-made climate change will never come again," they wrote in the study.
There is agreement on one aspect of the extermination trend: it is our fault
"It is amazing to me that humans have the ability to influence the earth system, in this case the biosphere, on truly geological time scales," Lowery said. "I think this really emphasizes how important the conservation is."
Scientists still emphasize whether Earth is really in the middle of another mass extermination.
Lowery does not think we have yet rejected in the sixth eradication area. But he and Fraass agree that bias over what constitutes this distinction is in addition to the point.
"We need to work to save biodiversity before it's gone. That's the important pick up here," Lowery said.
There is agreement on one aspect of the extermination trend, however: Homo sapiens is due. According to a 2014 survey, current extinctions are 1,000 times higher than they would be if people were not around.
"It's amazing that people have the capacity to damage the biosphere so seriously that it will take millions of years to recover," Lowery said.