116

Summary. There's no factual basis to the claim that there is a 0.1% annual risk of human extinction. What happened is that this figure was used by the authors of the Stern Review as a conservative assumption in their calculation of a discount rate for future costs and benefits, but a game of whispers has caused this context to be lost. Details. Let's chase ...


30

Possibly, but maybe not as severe as suggested. Basically the eruption of the Toba supervolcano caused a volcanic winter that decimated the human population at the time. There is evidence of this in the human genome. DNA mutates at a reasonably steady rate, so by looking at the genetic diversity of humans we can see that the population must have been very ...


21

I've found a few sources on the subject that discuss the hypothesis. The first is by Hawks et. al.. On the second page, A 2-Myr Bottleneck There are many reasons to believe that there may have been a number of severe population size bottlenecks on the lineage leading to living humans, principally because of the many speciation events that must have occurred....


12

This is impossible to answer conclusively, since there's no definition provided for either "Zombie", "Apocalypse", or even "possible" (which includes things with miniscule probability, as long as they don't violate laws of nature). Nor of how many scientists said so and if it was in peer reviewed publication. As such, yes, "...


10

A 10% chance of 6-10°C by the end of the century is not in the findings of the IPCC AR5 (2013) report. This seems relevant given the reference to "UN approved climate models" in the claim. The summary in the IPCC AR5 report is (pg. 1031): Global mean temperatures will continue to rise over the 21st century if greenhouse gas (GHG) ...


5

776 species have gone extinct since year 1500 according to the most comprehensive global survey of threatened species, The IUCN Red List of Threatened Species. The number of species that go extinct without anyone noticing may probably be large, but not 10,000 times as high as the number of species confirmed by IUCN. Figures like "10,000 and 100,000 species ...


5

Nope. If insects ran rampant and ate everything, we could just eat them. Could Less Meat Mean More Food? “Nutritionally, it is excellent food,” says Arnold van Huis, an entomologist at Wageningen University in the Netherlands. “It’s the same or even better than conventional meat, fish, or poultry.” Just 100 grams of caterpillars can provide all of an adult’...


5

No, it will miss us, in this orbit, by about 0.428 astronomical units (64 million km, 40 million miles). Here is the latest technical tracking information on "C/2012 S1 (ISON)". It is a Java app that can be used to model the orbits, and is used and vetted by hundreds or thousands of astronomers every night. If you animate the orbit, you will see the you ...


4

The link that Michael Pryor mentioned: The smoke would form a stratospheric smoke layer that would block sunlight from reaching the surface of Earth for a period of about ten years. Probably has a couple inaccuracies. The U.S and Russia keep more than 2000 strategic nuclear weapons on high-alert See YouTube: A Time-Lapse Map of Every Nuclear ...


3

No. According to Princeton University, Deforestation is the leading cause of species extinction. Evidence to date suggests that deforestation is currently, and is projected to continue to be, the prime direct and indirect cause of reported extirpations. For example, it is predicted that up to 21% of Southeast Asian forest species will be lost by ...


2

Well, there are many objects out there that "may or may not" impact Earth. ISON (a "sungrazer," incoming from the Oort Cloud) is headed for a close roundabout of our Sun and may wholly or partially disintegrate or may come back round intact. Earth MAY pass through the remnants of very tiny particles of ISON's pass-through; most, burning up in the atmosphere ...


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