The video is associated with the Voluntary Human Extinction Movement, a group which I found fascinating today, simply because it pushes environmentalism to one of the furthest extremes. It a way it's a cartoonish representation of Agent Smith's in "The Matrix:"
"Human beings are a disease, a cancer of this planet. You're a plague and we are the cure."I don't things are that bad by any means. A professor of mine once said that if human beings ruin the environment and destroy life as we know it, the planet won't care. Earth has suffered mass extinctions on a global scale hundreds of times and if we kill ourselves and 70% of life, the planet will just start over. Sucks for us, sure, but we learn the hard way.
From "Extinction," John Baez, 8 April 2006:
27% of all families and 57% of all genera went extinct.
This was the second biggest extinction of marine life, ranking only below the Permian extinction. There was only life in the seas at this time, and more than one hundred families of marine invertebrates died, including two-thirds of all brachiopod and bryozoan families. One theory is that as the continent Gondwana drifted over the south pole, there was a phase of global cooling, and so much glaciation took place that sea levels were drastically lowered.
19% of all families and 50% of all genera went extinct.
By this point there were plants, insects and amphibians on land, fish in the seas, and huge reefs built by corals and stromatoporoids. The continents of Uramerica and Gondwana were just beginning to move together to form Pangea. The extinction seems to have only affected marine life, but 70% of marine species went extinct! Reef-building organisms were almost completely wiped out, so that coral reefs returned only with the development of modern corals in the Mesozoic. Brachiopods, trilobites, and other sorts got hit hard. Since warm water species were the most severely affected, many scientists suspect another bout of global cooling. There may have also been a meteorite impact, but it seems this extinction was not a sudden event.
57% of all families and 83% of all genera went extinct.
At the end of the Permian there was one supercontinent, Pangea. There were many sorts of reptiles and amphibians on land, together with many plants, especially ferns but also conifers and gingkos. There were also complicated coral reef ecologies undersea. After the extinction, we mainly see fossils of one species of reptile on land: a medium-sized herbivore called Lystrosaurus. We also mainly see fossils of just one species of sea life, a brachiopod called Lingula. Eventually other species seem to reappear - the so-called "Lazarus taxa", named after the Biblical character who returned from the dead. Clearly they must have survived the extinction event, but in very low numbers.
This was the largest disaster that life has ever yet faced on our planet.
Perhaps 90% or even 95% of all species went extinct. (The figure of 83% above comes from some papers by Sepkoski, who tried to calculate the number of families and genera that died out in each of the Big Five extinctions.
It took about 50 million years for life on land to fully recover its biodiversity, with the rise of many species of dinosaurs. Nothing resembling a coral reef shows up until 10 million years after the Permian extinction, and full recovery of marine life took about 100 million years.
The causes remain controversial: some scientists blame an asteroid impact, while others blame severe global warming and a depletion of oxygen in the atmosphere due to prolonged massive volcanic eruptions in Siberia - we see signs of these in lava beds called the "Siberian traps". On the other hand, Benton and others argue that the rise of carbon in the atmosphere at this time is only explicable if there was also a catastrophic release of methane from gas hydrates under the ocean.
23% of all families and 48% of all genera went extinct.
By the end of the Triassic there was again a variety of reptiles on land and in sea. But the reptiles were completely different from those at the end of the Permian, and the biodiversity had not completely recovered: for example, there were no truly large predators. There were primitive conifers and gingkos; ferns were not so dominant as before. There were also frogs, lizards, and even the first mammals.
The extinction at the end of the Triassic destroyed about 20% of all marine families, many reptiles, and the last of the large amphibians - opening niches for the dinosaurs of the Jurassic. The cause of this extinction remains obscure, but it's worth noting that this was about the time when the supercontinent Pangea began splitting into Laurasia and Gondwanaland, with massive floods of lava in the Central Atlantic Magmatic Province - perhaps one of the largest igneous events in the earth's history.
17% of all families and 50% of all genera went extinct.
By the Cretaceous there were dinosaurs and flowering plants on land, many new insects taking advantage of the flowering plants, and modern fish. Continents were beginning to resemble the current configuration. In the disaster at the end of this period all the dinosaurs died out, as well as many species of plants, diatoms, dinoflagellates, ammonoids, brachiopods, and fish. Often called the "KT" extinction, this was the smallest of the Big Five - it's mainly interesting because it led to the rise of mammals, and in particular, us. As explained above, many scientists believe this extinction was due to an asteroid impact at Chicxulub. Another popular theory is that it was caused by the enormous volcanic eruptions which formed the lava beds in India known as the "Deccan Traps". Either way, we know it took 10 million years for biodiversity to recover from this mass extinction.
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