Earth has experienced five mass extinctions caused by natural phenomena, but a new study suggests a sixth event is underway and human activities are to blame.
The research, led by the University of Hawaii at Manoa, reveals our planet has lost 150,000 to 260,000 (7.5 to 13 percent) of all its two million known species since 1500.
Although some are in denial that the dramatic decline will amount to a mass extinction, billionaire Elon Musk is one who believes increased rates of species extinctions is inevitable.
Replying to a tweet announcing the release of the study, Musk commented: ‘There is a 100 [percent] chance of *all* species extinction due to expansion of the sun.’
However, the tech tycoon also offers up a solution – humanity must make life multiplanetary.
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![Although some are in denial that the dramatic decline will amount to a mass extinction, billionaire Elon Musk is one who believes increased rates of species extinctions is inevitable](https://i.dailymail.co.uk/1s/2022/01/17/22/53042277-10412023-image-a-17_1642458650229.jpg)
Although some are in denial that the dramatic decline will amount to a mass extinction, billionaire Elon Musk is one who believes increased rates of species extinctions is inevitable
Musk’s tweet echoes statements he made in December 2021 to Time magazine, which he proposed creating a ‘futuristic Noah’s Ark’ to take animals to Mars in order to save them from extinction on Earth.
‘The next really big thing is to build a self-sustaining city on Mars and bring the animals and creatures of Earth there,’ he said.
‘Sort of like a futuristic Noah’s ark. We’ll bring more than two, though – it’s a little weird if there’s only two.’
Although scientists have ridiculed Musk for the plan, the billionaire’s stance on a sixth extinction could be accurate.
![The study, led by Robert Cowie with the University of Hawaii, notes that the Red List of Threatened Species includes mostly birds and mammals, but leaves out most invertebrates - a group that has seen a dramatic loss](https://i.dailymail.co.uk/1s/2022/01/17/22/53042279-10412023-image-a-18_1642458713185.jpg)
The study, led by Robert Cowie with the University of Hawaii, notes that the Red List of Threatened Species includes mostly birds and mammals, but leaves out most invertebrates – a group that has seen a dramatic loss
![The study notes that the Red List seems to avoid Romeo Error and does not include all extinct species, thus underestimating how many have actually disappeared from the Earth. Pictured is recent extinct Endodontidae from Rurutu that are not on the Red List](https://i.dailymail.co.uk/1s/2022/01/17/22/53041905-10412023-image-a-19_1642458737695.jpg)
The study notes that the Red List seems to avoid Romeo Error and does not include all extinct species, thus underestimating how many have actually disappeared from the Earth. Pictured is recent extinct Endodontidae from Rurutu that are not on the Red List
The study, led by Robert Cowie with the University of Hawaii, notes that the Red List of Threatened Species includes mostly birds and mammals, but leaves out most invertebrates – a group that has seen a dramatic loss.
According to the International Union for Conservation of Nature Red List, human activity is known to have forced 869 species to extinction in the last 500 years.
‘Incorporating estimates of the true number of invertebrate extinctions leads to the conclusion that the rate vastly exceeds the background rate and that we may indeed be witnessing the start of the Sixth Mass Extinction,’ reads the study published in the journal Biological Reviews.
![Pictured is an Eskimo curlew from Audubon that disappeared around 1827, but is not listed as such, for fear of committing the ‘Romeo Error’](https://i.dailymail.co.uk/1s/2022/01/17/22/53041909-10412023-Pictured_is_an_Eskimo_curlew_from_Audubon_that_disappeared_aroun-m-21_1642458921113.jpg)
Pictured is an Eskimo curlew from Audubon that disappeared around 1827, but is not listed as such, for fear of committing the ‘Romeo Error’
The study notes that the Red List seems to avoid Romeo Error – uncritical acceptance of pronouncements and assumptions of extinction – and does not include all extinct species, thus underestimating how many have actually disappeared from the Earth.
And this is largely observed among invertebrate species, which are typically recorded only locally and sometimes only one specimen, making them impossible to assess with the Red List criteria.
‘For instance, ~ 20% of Australian Neuroptera are known from a single specimen or a single locality; in a random sample of terrestrial molluscs worldwide, 30% were known only from the original description and 33% from only one locality; in a random sample of Coleoptera, 53% were known only from a single locality and 13% from a single specimen; among species of Trichoptera newly described in 2011–2014, 45% were based on singletons; and of 2,198 worldwide mantids, 48% are reported based on single specimens,’ the study reads.
![The team also says the Red Lists is not a good basis to assess global extinction because 'it is far from comprehensive and biased taxonomically. Pictured is a parasite that went extinct when its host, the kiwi, was transferred to a predator-free island - it is also not on the Red List](https://i.dailymail.co.uk/1s/2022/01/17/22/53041919-10412023-image-a-23_1642459051234.jpg)
The team also says the Red Lists is not a good basis to assess global extinction because ‘it is far from comprehensive and biased taxonomically. Pictured is a parasite that went extinct when its host, the kiwi, was transferred to a predator-free island – it is also not on the Red List
The team also says the Red List is not a good basis to assess global extinction because ‘it is far from comprehensive and biased taxonomically, and it is impossible to evaluate the vast numbers of species, notably invertebrates, according to the IUCN categories and criteria, not only because of their sheer numbers but also because we simply do not have adequate data.’
‘Including invertebrates was key to confirming that we are indeed witnessing the onset of the Sixth Mass Extinction in Earth’s history,’ said Cowie.
Unfortunately, along with science denial taking a foothold in modern society on a range of issues, the new study points out that some people also deny that the sixth extinction has begun.
Additionally, others accept it as a new and natural evolutionary trajectory, as humans are just another species playing their natural role in Earth’s history.
Some even consider that biodiversity should be manipulated solely for the benefit of humanity.
‘Humans are the only species capable of manipulating the biosphere on a large scale,’ Cowie emphasized.
‘We are not just another species evolving in the face of external influences. In contrast, we are the only species that has conscious choice regarding our future and that of Earth’s biodiversity.
‘Denying the crisis, accepting it without reacting, or even encouraging it constitutes an abrogation of humanity’s common responsibility and paves the way for Earth to continue on its sad trajectory towards the Sixth Mass Extinction.’