Humans speeding the extinction of species, study claims
Data science expert Gil David finds that human exploitation of Earth has led to 5,800 years-worth of extinctions from natural causes condensed into just 100 years
Sue Surkes is The Times of Israel's environment reporter
The rate at which species are becoming extinct is 58 times faster than it would be without human impact on the environment, Israeli data science expert Gil David has calculated.
David, whose blog, Data Science Storytelling, provides text, graphs and diagrams on a wealth of subjects, analyzed information from the International Union for the Conservation of Nature (IUCN), which holds the most comprehensive data on the world conservation status of biological species.
The organization also publishes a “red list” of all species that have become extinct or are most likely extinct because they have not been seen during the past 100 years.
“Since the beginning of life on Earth, there have been at least five mass extinctions in which over 75 percent of the animal and plant species disappeared from the face of the earth in a relatively short time,” David wrote. “How short? In geological terms, it means that in less than two million years [each time], most species became extinct.”
In nature, David wrote, two vertebrate species per million species become extinct every year. This equals two species per 10,000 species every 100 years.
It is a conservative estimate, he said, with some scientists quoting much lower rates of 0.1 extinctions per million species per year.
To get a more up-to-date picture, David sought IUCN information about 50,000 species of vertebrates belonging to the five main biological classes — mammals, reptiles, amphibians, birds and fish.
“If we compare the rate of species extinction in the last 100 years to the natural extinction rate of the species on Earth, it seems that, while we would expect to see about two extinctions for every 10,000 species in 100 years, and a total of about eight extinctions for all vertebrates, in practice, 520 species have become extinct and the current extinction rate is 58 times the natural rate. That is, for the number of vertebrate species that have become extinct in the last 100 years, it would naturally take 5,800 years to become extinct.”
“That means we were able to cram 5,800 years of extinction into just 100 years. And this is really frightening, because if this rate of extinction continues, within a few thousand years (and some say even a few hundred), over 75% of the species will disappear from the face of the earth, which took over a million years in previous mass extinctions.”
David blamed “unrestrained exploitation of the earth’s resources, massive deforestation, uncontrolled pollution of air, land, seas and lakes, intense and uninhibited hunting at sea and on land, and the selfish enslavement of animals and nature for our needs only.
“All of these and more destroy animals and eliminate their natural living and breeding areas,” he wrote.
But, he added, there is still a chance to stop what has become known as the sixth extinction.
“If we halt deforestation and return to nature some of the vast areas we have plundered to grow food for farm animals, we will stop air, sea and land pollution, slow global warming, protect the tens of thousands of endangered species, and allow ecosystems to recover and rehabilitate. If we could only act responsibly and understand that we are part of a complex ecosystem on Earth, perhaps we could stop the sixth mass extinction, whose consequences are likely to be catastrophic for the human race as well.”
David said it was important to note that the estimates he used were “extremely conservative, both in terms of the assumption about the natural extinction rate on Earth (which is probably lower) and in terms of the actual species extinction rate in recent centuries (which is probably higher). This reinforces the hypothesis of many experts that the sixth mass extinction has already begun and is entirely human-made.”
