Entire Sea Floor, Food Chain Face Shakeup, Fossil Data Suggests
There’s more worrying news out today about the health of the world’s oceans, with an Australian paleontologist — using the largest-ever sampling of fossil data – concluding the Earth is facing a mass extinction larger than even the end of the dinosaur age.
John Alroy of Sydney’s Macquarie University published his findings in the latest edition of international journal Science, writing that the entire sea floor is undergoing a major shift, with an eradication so large, that it will overturn the balance of the current marine food chain. According to this report in the Sydney Herald Sun:
“Organisms that might have adapted in the past may not be able to this time,” Dr Alroy said.
The research shows a combination of human behaviour and climate change could have devastating affects on species across the planet.
“When there’s mass extinction all bets are off and anything could happen,” Dr Alroy said. “If you were standing around in the Cretaceous period, you would have no idea which groups would thrive and which would die out.”
“So what we’re basically doing as the human species collectively is we’re running this gigantic experiment with nature.”
It’s not the first time scientists have predicted a mass die-off and previous results have been more doom than actual gloom. Skewed sampling bases distorted results and resulted in false projections. In its analysis, New Scientist said Alroy’s predictions, however, may be the most-accurate to date:
For example, older genera were under-represented because older fossils are less likely than young ones to survive erosion and be found. And more samples may have been preserved in particular environments, further skewing results.
Alroy accounted for such distortions using a new sampling method called shareholder quorum sampling, which mathematically “dampens” the data from sites where a lot of samples have been found, for instance. “You’re giving a little less credit to some genera, because you know that you are missing others,” he explains.
As this is a new statistical method which “needs to be further vetted”, Alroy’s results are “unlikely to be universally accepted”, says Marshall, “but they help to pinpoint the critical issues.”
While we scuba divers and others bemoan the continuing destruction of the aquatic ecosystem, Alroy writes that a mass extinction actually might not be as horrific as it sounds.
There have already been three mass extinctions in Earth’s history with the last one coming 65 million years ago when an asteroid smashed into current-day Mexico and killed off the dinosaurs. That, however, made room for mammals to thrive. Online publication Rights Pundit follows on this idea, questioning how much the entire planet would be impacted:
A long-held theory about the need for biological diversity for recovery from mass extinctions is now being reconsidered. The fossil record paints a different picture, of diversity shifts where a species evolves and branches out into new species following a mass extinction.
The implications of this do tie in with concerns of the current loss rate of animal species. In recent decades, the environmentalist movement has been evolving itself from one merely focused on pollution to a political and even a religious movement. The cry of how human civilization is impacting the Earth has led to the geologists now referring to our present time as the Anthropocene Epoch. The previous geologic epoch was the Holocene Age.
That began about 12,000 years ago when the Ice Age started. Glaciers reshaped much of the Northern Hemisphere of Earth. The Holocene Epoch is itself, subdivided into the Hypsithermal and Neoglacial periods. Some geologists argue that the Anthropocene is actually a subdivision of the Holocene Epoch, starting at about the 18th Century through today.
The idea that humans can now alter the Earth is at the heart of the Climate Change debate. No one doubts that civilization can impact a local area. But to impact the entire planet remains questionable. Which brings us back to paleobiologist John Alroy. The fossil record shows that there is a consistent pattern in growth spurts of diversity. The average life span for a species is just a few million years.
In the end, Alroy suggests that the future is, by its nature, unpredictable and what happens next can’t be exactly determined by today’s events.
“The current mass extinction is not going to simply put things out of whack for a while, and then things will go back to where we started, or would have gone anyway,” said Alroy. Mass extinction “changes the rules of evolution.”