AI Reveals a Mass Extinction Scenario More Advanced Than Expected
The diagnosis of the conservation status of thousands of species is far from rosy
--
The scientific community lacks data on the conservation status of thousands of species. That makes it impossible to track their conservation prospects and determine the measures for their survival.
In the reference database, the IUCN (International Union for Conservation of Nature) Red List –which classifies the extinction risk of more than 147,500 species– between 10 percent and 20 percent of the cataloged entries are data deficient.
Scholars struggle to gather enough information on these species to qualify their condition and quantify how many specimens remain.
In this regard, a team of researchers from the Norwegian University of Science and Technology built a machine learning model to define how threatened these little-known species are.
The researchers trained an algorithm based on data from the tens of thousands of species on the Red List whose conservation status had already been assessed.
That allowed the algorithm to understand what factors threaten the conservation of a species.
The model was then applied to thousands of data-deficient species whose geographic distribution was at least known. And fifty-six percent of them were found to be endangered –an alarming figure suggesting a worse scenario than we thought.
There are more than 20,000 data-deficient species on the Red List. The model only worked with 7,699 of them, less than a third.
The study’s accuracy was confirmed when IUCN updated the status of 123 species on the Red List last year. The predictions proved correct with a 76% rate.
Timeline of Sixth Mass extinction
The diagnosis of the conservation status of most species on the planet is not rosy. Thousands of species face extinction, while already between 7.5 and 13 percent of the approximately two million known species have gone extinct since the 16th century.
Over millions of years of history, on five occasions, the Earth has lost most of its species in a short geological interval due to climate change and environmental destruction.
No less important, these five major mass extinctions –which occurred over the past 540 million years– coincided with a reversal of the carbon cycle.
In the modern age, carbon dioxide emissions have steadily increased. But it has always been difficult for scientists to estimate whether this significant carbon shift could lead to mass extinction.
MIT’s Department of Earth Sciences has identified “catastrophe thresholds” in the carbon cycle that would lead to an unstable environment first and a mass extinction later.
By 2100, the carbon cycle will be near or well beyond this threshold.
Meanwhile, a growing body of science collects evidence of abnormal extinction rates. Just between 2001 and 2014, some 173 species went extinct, a rate 25 times higher than the baseline extinction rate.
A study published in Nature early last decade estimated that three-quarters of animal species could disappear within three centuries.
University of California, Berkeley analyzed the current phenomenon –recognized as the sixth extinction– with the previous five, calculating the rate at which mammals have gone extinct over the past 65 million years.
At least 80 of the 5570 mammal species have gone extinct in the past five centuries, a rate higher than that documented for past mass extinctions.
The study’s authors argued the picture becomes even bleaker when adding the currently endangered species. Should they disappear, 75 percent of all mammals will be gone in just over three centuries.
Magnitude
In July, professor emeritus at Tohoku University Kunio Kaiho demonstrated a strong correlation between changes in global temperature and the extent of mass extinctions.
Over millions of years, abrupt climate changes and environmental destruction have led to great mass extinctions.
Specifically, according to the study, the largest extinctions occurred when temperatures dropped at least 7 degrees or rose 9 degrees Celsius.
In the case of global warming, nine degrees is almost double the estimate of an earlier study, according to which a 5.2°C increase in average global temperature would result in a mass extinction event comparable to previous ones.
Kaiho, the study’s sole author, claimed: “These results indicate that the greater the climate change, the greater the mass extinction.”
That does not automatically mean that the magnitude of the mass extinction we are approaching will reach the levels of previous ones.
A scenario where temperatures rise by nine degrees is estimated to be centuries away at worst.
In perspective, climate warming projections predict a 4.4 degree Celsius increase in temperatures by the end of the century.
Kaiho’s study does not deny the ongoing extinction process, but it does consider the hypothesis that it may be a lower-magnitude extinction, which historically has occurred more frequently.
Bottom line
The 2015 Pulitzer Prize-winning book The Sixth Extinction dealt with mounting evidence the Earth is approaching a sixth great mass extinction. A thesis reiterated by subsequent studies and papers.
Yet, some still reject this version. Denialism converges on the exaggeration of extinction rates and the perspective of the extinction process, considered a part of the evolutionary trajectory of life.
For skeptics, any extinction is offset by an equivalent origin of evolution. Moreover, humans are part of the natural world, and extinctions that occurred at their hands should therefore be considered a natural phenomenon.
Scientists have long concluded that the past five extinctions were productive for creating periods of species evolution, naming the process “creative destruction.”
Creative destruction plays a crucial role in evolutionary concepts. But in the previous five cases, the causes covered a spectrum of natural causes. The current one is human-caused.
The expansion of the human population and its interventions has been exponential over a few centuries, leading to extinction rates about two orders of magnitude higher than usual.
An extensive review of scientific literature on the sixth mass extinction concluded as follows:
“The prognosis for the survival of a large proportion of extant species is not good.[…] Denying the crisis, accepting it and doing nothing about it, or embracing it and manipulating it for the fickle benefit of people, defined no doubt by politicians and business interests, is an abrogation of moral responsibility.”
