1. Summary

The video discusses the world’s most severe extinction event, known as the End-Permian Mass Extinction. The video’s theory behind the cause of the End-Permian Mass Extinction is an ancient volcano chain, which spewed out carbon dioxide into the atmosphere, trapping heat and causing a global warming event. This heated the Permian oceans and caused them to lose oxygen, allowing bacteria to thrive and put out hydrogen sulfide (a toxic substance), which eventually bubbled out from the ocean and spread into the atmosphere, resulting in the deaths of land and sea creatures, and plants.

2. Why Watch This Video?

1. Are you curious about how the End-Permian Mass Extinction left very little geological evidence, compared to the mass extinction that wiped out the dinosaurs?
2. Have you ever wondered what triggered the greatest mass extinction event in Earth’s history?
3. Would you like to know about the rest of the events in the End-Permian Mass Extinction, and their effects on the global environment?

3. Key Terms

Ancient Volcanoes – An ancient volcano chain spewed out lava for around 1 million years, blanketing an area approximately the size of the continental United States. The remnants from these volcanoes can be found in present-day eastern Russia, in a region of volcanic rock known as the Siberian Traps. Most importantly, these volcanoes filled the atmosphere with carbon dioxide, causing a global warming event through heat being trapped by the released carbon dioxide.

Permian Oceans – The oceans that were present on the planet during the Permian Period. Prior to the atmosphere being flooded with carbon dioxide, the waters of these oceans were colder, meaning the waters were capable of holding large amounts of oxygen, which was beneficial to ocean-life at the time. Global warming caused warmer waters, meaning less oxygen was able to be carried by the oceans. This made life for aerobic creatures difficult, but enabled anaerobic creatures, such as bacteria.

Hydrogen Sulfide – Made up of the elements hydrogen and sulfur, hydrogen sulfide (or H₂S), is a colorless and very toxic poisonous gas, known for smelling like rotten eggs. This gas was produced by anaerobic ocean bacteria (now thriving in the oxygen-depleted waters), and over time, enough hydrogen sulfide accumulated to bubble out of the ocean and fill the atmosphere. The video claims hydrogen sulfide is the main culprit behind the vast amounts of life lost during the End-Permian Mass Extinction.

4. Loose Ends

Loose end #1: Date of Occurrence – The date of occurrence is not stated in the 3 – 10 minute time-frame of the video, so, as to be clear, the End-Permian Extinction occurred around 250 million years ago, between the Permian and Triassic Periods.

Loose end #2: Amount of Life Lost – The video states in the introduction (outside of the 3 – 10 minute time-frame) that approximately 95% of marine life was made extinct by the event. This is a commonly-made incorrect statement, due to another mass extinction occurring before the End-Permian Extinction, called the Guadalupian Mass Extinction. The estimate of 95% comes from the casualties of both events being combined. When looking at the End-Permian Extinction alone, the death-rates are about 60% of the marine genera, with ~80% of the species dying out.

Loose end #3: Hydrogen Sulfide Color – The water sample containing hydrogen sulfide shown in the video is distinctly pink/purple-looking. However, to be clear, hydrogen sulfide is a colorless gas, identifiable by the smell of rotten eggs. The coloring in the sample comes from “purple sulfur bacteria”, which thrives in hydrogen sulfide. The anaerobic bacteria, present in the lake’s warm, low oxygen water, is drawn to the hydrogen sulfide, and is also present in the water sample drawn from the lake. Furthermore, the video claims that the sudden release of hydrogen sulfide from the oceans into the air was responsible for the vast amount of deaths during the End-Permian Extinction. This, however, might not be the case. As per the course textbook, the deep sea was stagnated around the time of the End-Permian Extinction. Without normal ocean mixing, it would have been very difficult for hydrogen sulfide to make its way to the surface and into the atmosphere.

5. Self-Test Questions

Question 1: Which of the following statements is correct?

Answer a: The End-Permian Extinction occurred 250 million years ago, with ~95% of all life dying out

Answer b: The End-Permian Extinction occurred 250 million years ago, with an estimated death-rate of 60% for all genera, with 80% of the species dying out

Answer c: The End-Permian Extinction occurred between the Permian and Triassic Periods, with an estimated death-rate of 60% for marine genera, with 80% of the species dying out

Answer d: The End-Permian Extinction occurred between the Permian and Triassic Periods, with ~95% of all life dying out

 

Question 2: What role did the Permian oceans play in the End-Permian Extinction?

Answer a: The oceans became warmer and lost oxygen, which made aerobic life difficult, and allowed anaerobic bacteria to thrive and produce hydrogen sulfide

Answer b: The oceans became colder and gained oxygen, which enabled aerobic life and caused the atmosphere to be flooded with oxygen

Answer c: The oceans became warmer and gained oxygen, which made aerobic life easier, but allowed ocean bacteria to thrive and release carbon dioxide into the waters

Answer d: The oceans became colder and gained oxygen, which enabled aerobic life, but allowed anaerobic bacteria to produce hydrogen sulfide

 

Question 3: How is the End-Permian Extinction different from an asteroid-based mass extinction?

Answer a: No comet or asteroid materials from the same time were found, or a crater. As well, no fossils from the same time can be used to examine the event

Answer b: No comet or asteroid materials from the same time were found, or a crater. Only fossils from the same time can be used to examine the event

Answer c: No comet or asteroid materials from a corresponding time were found, but a crater with fossils from the same time has been identified

Answer d: Comet and asteroid materials from a corresponding time have been found, but no crater or fossils from the same time have been able to be located

 

Question 4: The Siberian Traps are…

Answer a: The name for the ancient volcano chain responsible for the End-Permian Extinction

Answer b: A large region of granite, caused by an ancient volcano chain

Answer c: A large region of limestone, caused by an ancient volcano chain

Answer d: The area covered by lava from the ancient volcano chain that set off the End-Permian Extinction

 

Question 5: According to the video, the trigger for the End-Permian Extinction was…

Answer a: A period of global cooling, following the release of oxygen into the atmosphere

Answer b: The release of hydrogen sulfide into the atmosphere

Answer c: Gasses released by ancient volcanoes into the atmosphere

Answer d: An asteroid, much like the other well-known mass extinctions

6. Answers to Self-Test Questions

1. C – The commonly-seen estimated death-rate of 95% from the video is incorrect, as it factors in the Guadalupian Mass Extinction. The correct estimate is a death-rate of 60% for marine genera, with 80% of the species dying out. As well, the accepted time for the End-Permian Extinction is 250 million years ago, between the Permian and Triassic Periods.

2. A – The Permian oceans became warmer, as a result of global warming from the carbon dioxide released by the volcanoes. Because of this, the oceans lost oxygen, enabling anaerobic bacteria to produce the hydrogen sulfide that would later be responsible for the incredibly large loss of life.

3. B – According to the video, the End-Permian Extinction does not display evidence of an asteroid impact. No comet or asteroid materials corresponding to the correct time are available, nor is an impact crater. Instead, the video’s researchers state that the only geological evidence they have are fossils from the same time, which is the only similarity between the End-Permian Extinction and an asteroid-based mass extinction (like the one that wiped out the dinosaurs at the end of the Cretaceous). This led the video’s researchers to pursue other theories behind the cause of the End-Permian Extinction.

4. D – The Siberian Traps are a large area of volcanic rock, created by the ancient volcanoes which set off the End-Permian Extinction by releasing vast amounts of carbon dioxide into the atmosphere.

5. C – The trigger event was ancient volcanoes releasing carbon dioxide and other gasses into the atmosphere. This allowed the rest of the events to occur – a global warming period, ocean temperatures rising, the rise of hydrogen sulfide-producing bacteria, the release of hydrogen sulfide into the atmosphere, and the deaths of ~90% of marine life (when including the Guadalupian Mass Extinction).