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Is Our Planet Going the Way of the Dinosaurs?
We now think the big mass extinctions were caused by hydrogen sulfide bacteria. Two hundred hydrogen sulfide molecules among a million air molecules is enough to kill a human.

Most of the big mass extinctions have been caused by nasty volcanic events. The last one didn’t cause a mass extinction. It was in the Tertiary Period. This was in my own home state, Washington State, the Columbia River Basalts.
Out came all this basalt, as liquid lava, and a lot of the carbon dioxide came out too, but not enough to cause the Earth to go into a really nasty mass extinction. The mass extinctions caused by the basalts happen by simply heating the world. When you heat the world you heat the pole more than you do the equatorial region. When that happens, you start losing circulation. The only reason you have wind now is you have a hot spot and a cold spot and they’re trying to equilibrate. With an ocean current you have the same thing. You have a cold Antarctic and then you warm them up, the ocean circulation system is dampened down. There’s much less heat difference.
We already have very sluggish ocean circulation. The oceans are going oxic - losing their oxygen. They only keep oxygenated now because of this vigorous mixing. Even when you have oxygen in the atmosphere and contact with the surface, once you slow down any circulation, that whole basin can lose this oxygen. The Black Sea is the same case. It’s sits under a 21% oxygen atmosphere, and yet the Black Sea, except for the top several meters, in anoxic. It’s black because it’s producing a lot of sulfur-producing bacteria and there’s very nasty gasses that are produced.
We now think the big mass extinctions were caused by global anoxia. The oceans themselves were so sluggish that the hydrogen sulfide bacteria were produced in huge areas of the ocean. The bottom bubbles up to the surface and starts killing things - rotten egg killing. It would be extremely nasty. Hydrogen Sulfide poisoning is a horrible death. Two hundred hydrogen sulfide molecules among a million air molecules is enough to kill a human. Just breathing in 200 of those little things amid all the million you’re getting in oxygen and boom, you’re down, horribly down.
So, this is a really nasty poison and it was certainly present in past oceans during these short-term global warming events. That’s why it’s really spooky what we’re doing now.
In Their Own Words is recorded in Big Think's studio.
Image courtesy of Shutterstock
A 62-year old Russian mystery (and conspiracy theory) has been solved
Some mysteries take generations to unfold.
Winter in the Ural Mountains
- In 1959, a group of nine Russian hikers was killed in an overnight incident in the Ural Mountains.
- Conspiracies about their deaths have flourished ever since, including alien invasion, an irate Yeti, and angry tribesmen.
- Researchers have finally confirmed that their deaths were due to a slab avalanche caused by intense winds.
a: Last picture of the Dyatlov group taken before sunset, while making a cut in the slope to install the tent. b: Broken tent covered with snow as it was found during the search 26 days after the event.
Photographs courtesy of the Dyatlov Memorial Foundation.
<p>Finally, a <a href="https://www.nature.com/articles/s43247-020-00081-8" target="_blank">new study</a>, published in the Nature journal Communications Earth & Environment, has put the case to rest: it was a slab avalanche.</p><p>This theory isn't exactly new either. Researchers have long been skeptical about the avalanche notion, however, due to the grade of the hill. Slab avalanches don't need a steep slope to get started. Crown or flank fractures can quickly release as little as a few centimeters of earth (or snow) sliding down a hill (or mountain). </p><p>As researchers Johan Gaume (Switzerland's WSL Institute for Snow and Avalanche Research SLF) and Alexander Puzrin (Switzerland's Institute for Geotechnical Engineering) write, it was "a combination of irregular topography, a cut made in the slope to install the tent and the subsequent deposition of snow induced by strong katabatic winds contributed after a suitable time to the slab release, which caused severe non-fatal injuries, in agreement with the autopsy results."</p><p>Conspiracy theories abound when evidence is lacking. Twenty-six days after the incident, a team showed up to investigate. They didn't find any obvious sounds of an avalanche; the slope angle was below 30 degrees, ruling out (to them) the possibility of a landslide. Plus, the head injuries suffered were not typical of avalanche victims. Inject doubt and crazy theories will flourish.</p>Configuration of the Dyatlov tent installed on a flat surface after making a cut in the slope below a small shoulder. Snow deposition above the tent is due to wind transport of snow (with deposition flux Q).
Photo courtesy of Communications Earth & Environment.
<p>Add to this Russian leadership's longstanding battle with (or against) the truth. In 2015 the Investigative Committee of the Russian Federation decided to reopen this case. Four years later the agency concluded it was indeed a snow avalanche—an assertion immediately challenged within the Russian Federation. The oppositional agency eventually agreed as well. The problem was neither really provided conclusive scientific evidence.</p><p>Gaume and Puzrin went to work. They provided four critical factors that confirmed the avalanche: </p><ul><li>The location of the tent under a shoulder in a locally steeper slope to protect them from the wind </li><li>A buried weak snow layer parallel to the locally steeper terrain, which resulted in an upward-thinning snow slab</li><li>The cut in the snow slab made by the group to install the tent </li><li>Strong katabatic winds that led to progressive snow accumulation due to the local topography (shoulder above the tent) causing a delayed failure</li></ul><p>Case closed? It appears so, though don't expect conspiracy theories to abate. Good research takes time—sometimes generations. We're constantly learning about our environment and then applying those lessons to the past. While we can't expect every skeptic to accept the findings, from the looks of this study, a 62-year-old case is now closed.</p><p> --</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank" rel="noopener noreferrer">Facebook</a>. His most recent book is</em> "<em><a href="https://www.amazon.com/gp/product/B08KRVMP2M?pf_rd_r=MDJW43337675SZ0X00FH&pf_rd_p=edaba0ee-c2fe-4124-9f5d-b31d6b1bfbee" target="_blank" rel="noopener noreferrer">Hero's Dose: The Case For Psychedelics in Ritual and Therapy</a>."</em></p>As we approach death, our dreams offer comfort and reconciliation
As patients approached death, many had dreams and visions of deceased loved ones.
One of the most devastating elements of the coronavirus pandemic has been the inability to personally care for loved ones who have fallen ill.
Surprising new feature of human evolution discovered
Research reveals a new evolutionary feature that separates humans from other primates.
Human evolution.
- Researchers find a new feature of human evolution.
- Humans have evolved to use less water per day than other primates.
- The nose is one of the factors that allows humans to be water efficient.
A model of water turnover for humans and chimpanzees who have similar fat free mass and body water pools.
Credit: Current Biology
Skepticism: Why critical thinking makes you smarter
Being skeptical isn't just about being contrarian. It's about asking the right questions of ourselves and others to gain understanding.
