Changing Planet

The Sixth Great Extinction: A Silent Extermination


Lonesome George is a large, mud-loving Pinta tortoise (Geochelone elephantopus abingdoni), living out his long life in  the Galapagos Islands. In 1971, George was found alone on Pinta Island and taken to the Charles Darwin Research Station, where scientists theorized that he was the last of his subspecies on the planet. When he dies, his genetic lineage will disappear forever. Unfortunately, his companionless circumstances are not unique. In fact, we are in the midst of the Sixth Great Extinction, an event characterized by the loss of between 17,000 and 100,000 species each year.


The first extinction, named the Ordovician-Silurian extinction, occurred around 440 million years ago (m.y.a.). Scientists hypothesize that both a southerly continental drift that led to a drastic decrease in temperatures and radiation caused by the collapse of a massive star known as a hyper nova may have caused this massive loss of diversity on Earth.

The second extinction was the Late Devonian. Approximately 370 m.y.a., there was a sharp decrease in marine reef biodiversity. Many factors may have played a part in the Late Devonian extinction, but the causes remain mostly unknown.

Around 245 million years ago, during the Permian-Triassic extinction event, marine species died off to such an extent that oceanic reefs did not exist anywhere on the planet for ten million years. A combination of factors, including volcanic eruptions, climate change and a possible meteorite impact, made this the largest historical extinction event.

In the Triassic-Jurassic extinction, circa 210 m.y.a., 48 percent of genera vanished from the earth, including 80 percent of quadrupeds and half of all marine invertebrates. Although the causes of this event are unknown, scientists believe that volcanic activity contributed to extinctions.

The Cretaceous-Paleogene extinction event, circa 65 m.y.a. (formerly known as the Cretaceous-Tertiary or K-T), is best known for the extinction of the dinosaurs and nearly all large animal species. During this event, temperatures increased by as much as 57 degrees Fahrenheit (32 degrees Celsius) and sea levels rose as much as three hundred meters.

During each extinction event, between 50 and 95 percent of the planet’s life was lost, resulting in dramatically changed biotic characteristics. Generally, ten million years pass before biodiversity reaches pre-event levels.


The Sixth, however, may be the most catastrophic in history. It is estimated that half of all plants, animals and birds on the planet will die off before 2100. This extinction is the first to occur during the existence of homo sapiens, and it simultaneously began 100,000 years ago, a date that corresponds with the beginnings of our dispersion from Africa. In fact, this extinction is almost exclusively human driven.

There are many contributing factors to the Sixth Great Extinction; today, destruction of habitat, introduction of alien species and pollution claim the most species. Extinctions are also caused by overexploitation of species for consumption, collection and trade, agricultural monoculture, human-induced climate change, nitrogen loss in soil and oceanic acidification as a result of a warming climate, and urbanization leading to sedimentation and soil erosion. Growing human populations have led to increased demand for natural resources, and with a current world population of more than seven billion people, our demands, many of which require environmentally damaging practices to fulfill, will continue to grow.


Since most people probably cannot name a single recently extinct species, does it really matter to the human race whether we save biodiversity or let much of it disappear into the history books? The answer is a very strong and profound, Yes. By failing to recognize the importance of biodiversity, we may be assuring the demise of our own human species, as well as the destruction of most other species on Earth. We need biodiversity.

Biodiversity provides climate stability, nutritiously varied and abundant foods, medicines, clean water, pollination of crops, disease-control, cultural diversity, environmental knowledge, food-chain stability, and oxygen.

The world’s leading scientists suggest that conservation measures, sustainable development, stabilization of the human population and the support of environmentally responsible economic development will be essential in halting the extinction crisis. Read more at Izilwane, and join us in our quest to nurture an appreciation for biodiversity by becoming an eco-reporter.

Read the original article here.


Celâl Sengör, A.M., Atayman, Saniye and Sinan Özeren. 2008. A scale of greatness and causal classification of mass extinctions: Implications for mechanisms. PNAS September 9, 2008. Vol. 105 no. 36.

Eldredge, N. 2001 “The SixthExtinction.”

Leakey, R. and Lewin, R. 1996. The Sixth Extinction: Patterns of life and the future of humankind. First Anchor Books.

Whitty, J. 2010. “Gone: Mass Extinction and the Hazards of Earth’s Vanishing Biodiversity.” Mother Jones. Accessed September 10, 2010 at:

Wilson, E.O. 2010, “Only Humans Can Halt the Worst Wave of Extinction Since the Dinosaurs Died.” Accessed July 15, 2010 at:


— Photos by Jonmikel and Kathryn Pardo


Voices for Biodiversity (V4B) is an online conservation media magazine that shares the stories of people from around the globe in order to help all species survive and thrive together. The e-zine is a gathering place for those who believe that humanity’s health and well-being depend upon the health and well-being of other species and the ecosystems that support us all. Voices for Biodiversity shares the stories of eco-reporters from around the world, using the ancient human art of storytelling to connect people with each other, other species, and the natural world. The magazine’s goal is to alter human behavior in such a way as to connect the human animal with the global ecosystem in order to stem biodiversity loss and arrest the sixth extinction of species taking place in this time, the Age of the Anthropocene.
  • Frank Hatch

    Invitation to Join an Upgraded Species:

    This is an invitation for functional individuals of a corrupt species – i.e., the human species called, “Man.” This Invitation was originally offered by the first New Man or Son of Man, but it has since collected a swamp of clerical additions. However, after two thounsand years, the invitation is still open. Indeed, in the moment before your death, the invitation will still be open to you.

    Definitions: Functional and Non-functional Individuals:

    Best Regards,

    Frank Hatch
    Initial Mass Displacements

  • […] mass culture and away from reality. In addition to triggering climate chaos, we’ve initiated the Sixth Great Extinction, and we revel in its acceleration as one more sign of […]

  • […] Men tempoet i utryddelsen av arter, tapet i biofangfoldet, er i dag så stort at forskerne mener at vi kan være midt oppe i den sjette store utryddelsen. […]

  • […] dough, but it’s still rather small when you consider that this could be all it takes to stop the sixth great extinction. Which, yeah, your sushi habit is contributing to. So, really, what’s a better use of 12 bucks? […]

  • […] theorize that we are currently amid a sixth great extinction, one marked by the loss of an estimated 17,000-100,000 species each year. Our species, homo […]

  • […] Scientists predict there are even species that become extinct before they are discovered. National Geographic says we are in the midst of the Sixth Great Extinction, the first mass extinction to occur during […]

  • […] (maybe as high as 140,000) species a year to extinction. The technical term for this is “the Sixth Great Extinction” with the Fifth, for those keeping score at home, being the one that killed off the dinosaurs.  […]

  • […] it or not, the sixth wave of extinction is upon us. By the end of the century nearly 50% of all species on the planet may be […]

  • […] explored the science and fantasy of creating gadgets for animals to ‘leap frog’ the 6th wave of extinction. As Karolina, one of our attendees put it, “Still buzzing after today’s Parlor & […]

  • Robert Landbeck

    When Einstein wrote: “Problems cannot be solved by thinking within the framework in which they were created”, applied to the Sixth Mass Extinction, one must ponder whether the species that created the problem, US, tied to it’s evolutionary roots, even has the potential to either intellectually define or implement a solution. Probably not!

    Yet for anyone with the honesty and critical self scrutiny to draw that conclusion, that is not to say that solution exists, only that using Einstein’s logic, the solution cannot in principle be of human intellectual origin!

  • zach wood

    i’m scared….. i’m really really scared…… i don’t want to die….. *sobs* i don’t want to die!

  • […] death-of-birth among the passenger pigeons was one part of the ongoing Sixth Great Extinction.  It may not have been exclusively the fault of Homo sapiens, but there can be no doubt that our […]

  • zach wood

    don’t worry! i love you! you will not die!

  • […] It is estimated that 50% of all plants, animals, and birds will die off by the year 2100, with lead scientists calling the current loss of life, “The 6th Extinction.” (National Geographic) […]

  • […] planet, staring down the barrel of a ten billion-human population explosion, on the brink of the sixth wave of extinction. The summers get hotter, the winters weirder. In our hearts we know we can’t beat our global […]

  • […] urban expansion. The lack of countryside and green space will ultimately contribute to the sixth recorded mass extinction of animal and plant […]

About the Blog

Researchers, conservationists, and others share stories, insights and ideas about Our Changing Planet, Wildlife & Wild Spaces, and The Human Journey. More than 50,000 comments have been added to 10,000 posts. Explore the list alongside to dive deeper into some of the most popular categories of the National Geographic Society’s conversation platform Voices.

Opinions are those of the blogger and/or the blogger’s organization, and not necessarily those of the National Geographic Society. Posters of blogs and comments are required to observe National Geographic’s community rules and other terms of service.

Voices director: David Braun (

Social Media