The Sixth Mass Extinction

It is a well documented fact that human activity can push other species to extinctions. From the Dodo to the Thylacine we have dealt them a deathly blow primarily with our unsustainable overconsumption of resources. We are no stranger to the concept of extinction, indeed we are daily bombarded with adverts asking for donations to save a species from extinction. Yet a special analysis published in the scientific journal Nature which uses the most reliable data available to create a graphic status report of the life on Earth, still strikes a catastrophic tone.

Over the planets history (4.5 billion years approximately) there have been five previous mass extinctions, the most iconic of which is the Cretaceous-Jurrasic extinction which caused the dinosaurs to go extinct. Previously these mass extinctions have been caused by geological or astronomical events, however a new cause looks set to emerge: overexploitation and human interaction.

The idea of evolution is relatively new, emerging in revolutionary France. Previous to the work of French anatomist Cuvier, it was widely regarded that no species had ever gone extinct and that any fossils discovered belonged to species which had simply migrated to different climates. For example it was believed that the bones of mammoths found in Siberia actually belonged to something which had washed North in the great flood of Genesis, as clearly there were no elephants in Russia.

Compared to Cuviers day, extinction is a scientific theory which we are fed almost from infancy. As a small child, we are aware that the dinosaur figurines which we play with belong to a beast which no longer exists, and as we develop we soon learn of their mass extinction as well as the plight of many modern day species such as pandas and tigers, thanks to the widely advertised work of the WWF and zoos. In effect we are mass fed the threat of extinction from such a young age that we can become numb to the scale of it.

In the last half of 2014, the Living Planet Index reported a 52% loss of wildlife in 40 years. Also the IUCN Red List was updated to include more than 76,000 species. However what the updated Red List also stressed was the lack of knowledge regarding how many species inhabit our planet, as 76,000 species equates to 4% of the 1.7 million known species. This lack of data makes it impossible to designate any threat level to groups which have not been vastly assessed such as invertebrates.

The analysis in Nature has used the most reliable date available to attempt to overcome the uncertainty regarding our gaps in knowledge however their results show that the scale of uncertainty is a real problem when it comes to extinction.Currently it is estimated that there are between 2 million and 5o million species of plants, fungi, and animals alive on Earth today. It is also estimated that there are between 500 and 36,000 extinctions per year. With this uncertainty in mind, the analysis has shown that 41% of all amphibian species currently look destined to follow in the footsteps of the Dodo. These amphibians are likely to be joined by 26% of all mammal and 13% of all birds.

The data has also been used to create predictions for the future. For example projections show that if there are 5 million animal species on Earth and they are disappearing at the higher estimate of 0.72% per year, then we will enter a period of mass extinction by 2200. Lower end predictions will place us within a mass extinction in a few thousand years.

The sole inflicter of the sixth mass extinction, will unfortunately be us: Homo sapiens.  Ironically our ingenuity as a species has allowed us to alter the planet in a way no species has done before, we have changed the composition of the atmosphere, we have altered the landscapes around us with agriculture and mining, and we have transported various species and diseases worldwide to places they could never have naturally reached.

Since prehistoric times species have been dealt a deathly blow by the exploitation of humans, from mastodons, to the Great Auks, and onto the Passenger Pigeon. There are lesser known species as well such as the Japanese Sea Lion, persecuted by fisherman and exploited for their skin and oil; or the Desert Bandicoot who suffered at the hands of introduced predators such as cats to their native homeland of Australia.

There are countless other extinct species each with their own sad tale, many of which will stay unheard of. It is all too common today for a new species to be discovered and declared endangered at the same time, many species are most likely disappearing before we even know they are there. As a result it is imperative that NGOs and governments work together to fill in the missing blanks and compile an accurate list of species and their rate of extinction.

As for the species which has started this tsunami of extinctions? Unfortunately for them it may be that their innovativeness was short-sighted and that their altering of the ecosystems which they are still so dependent will ultimately be their downfall.  As the anthropologist Richard Leakey warned “Homo sapiens might not only be the agents of the sixth extinction, but also risks being one of its victims.”

For More Information:

Biodiversity: Life – a Status Report 

The Guardian – Earth Faces Sixth “Great Extinction” 

 Living Planet Report 2014

IUCN Red List

The Sixth Extinction: An Unnatural History. Elizabeth Kolbert. (2014). Great Britain: Bloomsbury

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Emily Stewart
Owner of Inspirewildlife - a site dedicated to sharing positive conservation news stories from around the world. Zoo Management Graduate from University of Chester
Emily Stewart

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