Mass Extinction Events Trivia Quiz

Answer: The cause of the mass extinction must be obvious.

The major mass extinctions all occurred in the relatively short time frame of several million years (geologically speaking). Different types of phyla in different habitats which are spread across the planet must have become extinct in the catastrophe.

The causes of these mass extinctions are still subject to debate and have not left an obvious "smoking gun". Though the effect of mass extinctions can be seen today, even the most recent events do not have a cause that can be called obvious and beyond doubt.

Answer: Cambrian

The Cambrian mass extinction occurred 510-543 million years ago (mya) at a time when all organisms were marine dwelling. The Ordovician-Silurian event occurred about 444 mya, the late Devonian, about 360 mya and the End-Permian, about 250 mya.

Answer: End Permian

The End Permian, which occurred on the Permian-Triassic boundary, was the single greatest extinction event that has occurred on the planet. 96% of marine life and 70% of land life ceased to exist with only 1 in 20 species surviving. The Cretaceous-Tertiary event saw the end of the dinosaurs and the End Triassic extinction saw the demise of about 50% of species.

The Ordovician-Silurian extinction was the second largest extinction with 75% of all species dying out.

Answer: Cretaceous-Tertiary

The Cretaceous-Tertiary extinction saw 50% of all species vanish, including the dinosaurs. Scientists have found evidence of a crater on the Yucutan penisula called the Chicxulub crater that occurred in the 65 mya time frame. There is evidence of other impacts in the same time frame in the Ukraine and in the North Sea.

A major impact, also called a bolide impact, would cause dust and debris to be thrown up into the atmosphere, resulting in sunlight being blocked for a long period of time. Levels of atmospheric O2 would drop and the surface of the planet would cool. Species unable to adapt to these relatively rapid changes would die out.

Answer: K-T boundary

K is the traditional abbreviation for Cretaceous and T is the abbreviation for Tertiary. K-T commonly appears in many online articles and textbooks covering pre-historic eras. The K-T boundary also marks the end of the Mesozoic era and the beginning of the Cenozoic era. The boundary is also known as the Cretaceous-Paleogene boundary, or abbreviated to K-Pg.

Answer: Volcanic eruptions along a fissure expelling large amounts of low-viscosity lava.

Flood basalts are a series of volcanic eruptions that occurs along a large stretch of land or the ocean floor. This can occur on a continental level and huge amounts of basalt lava, lava that is very hot and with a low-viscosity, is expelled.

Answer: Collections of frozen methane pockets that form on continental shelves under the oceans.

The methane clathrates are lattices of the frozen gas and are found on the ocean floor on the continental shelves. If the ocean temperature rises quickly or the ocean pressure on the clathrates drops quickly, then these clathrates disintegrate and the methane is released.

This has a drastic effect on the oxygen levels in both the ocean and on land, conditions which many species can not survive.

Answer: Gamma ray burst.

A gamma ray burst is one of the most powerful forces in the universe and appears during the collapse of massive stars. If close enough to the Earth, GRB's can irradiate and kill any life near the surface of the planet. With improved astronomical measurement techniques, scientists have found evidence that such a GRB event occurred during the Ordovician-Silurian period and these rays hitting the atmosphere would produce nitrogen dioxide which caused sun-blocking smog and may have precipitated the ice age. GRBs were only discovered in the 1960s, so this theory as a cause of mass extinction is relatively new but has been appearing more frequently in journals and on science related programming such as the BBC and Discovery Channel.

Answer: Flood basalts

Basaltic lava eruptions in Siberia, or a flood basalt, has the strongest support as the primary cause of the Permian extinction. The Siberia Traps were a long province of igneous activity which had major eruptions during the Permian period spanning about one million years.

This activity was the equivalent of about 150,000 Krakatoa eruptions and wiped out most of the species on the planet. Pangaea did form in this time frame causing a reduction in coastlines and the largest drop in sea level ever found but this was a gradual process. Evidence of glaciation has also been found, but most scientists believe that this occurred too late to have caused an extinction event.

Answer: Marine reef builders.

The Devonian extinction was the most gradual of the major mass extinction events and caused the destruction of 70% of all species. There may have been release of methane clathrates since evidence of anoxic conditions has been found in shale. A major episode of global cooling also occurred which decimated marine life, especially the marine reef builders. Terrestrial plants, newcomers to this period and freshwater tetrapods were much less effected.

There were no mammals living in the Devonian era.

Answer: It allowed the dinosaurs to become dominant.

The cause of the End Triassic extinction event is not clear but possibilities include volcanic activity and release of gas hydrates. The result was 50% of the species on the planet were wiped out including 35% of animal life. The major drop in bio-diversity allowed the dinosaurs to emerge as a dominant species in the following Jurassic period. Pangaea did break apart but this was not caused by the extinction event.

There were, of course, no humans living in this period.

Answer: Nearly all woodland plant species died out.

The majority of extinctions were in the low-latitude or equatorial regions (those regions are not in the same planetary position as they are now). Most all woodland plant species were completely wiped out. Small crustaceans and bivalves fared relatively well. Gorgonopsians were successful predators until the Permian extinction when they were suddenly extinguished.

Answer: It allows acceleration of the evolution of some species.

Even the most devastating mass extinction events have left survivor species. Niches left by some of the more dominant species that died out can now be filled by survivors, allowing them to flourish and evolve more quickly. The small mammals that survived the K-T event eventually evolved to humans.

Some species which became extinct during these cataclysmic events were very robust and successful lifeforms, but were unable to survive the results of planet-wide catastrophe.

Answer: The dodo.

The Holocene Extinction Era starts about 13,000 years ago and continues to this day. Woolly mammoths, the woolly rhinoceros and the giant sloth died out 11,000 to 9,000 years ago. The dodo was first seen by Europeans on the island of Mauritius around 1600 but was extinct before the next century.

Answer: Humans.

With the mass extinction events and minor extinction events, species have flourished and then completely died out throughout Earth's history. The rise and dominance of humans and our influence on the planet is causing many scientists to believe that we have accelerated the extinction of other species in a relatively short time frame compared to the other extinction events. Our expansion, resulting in loss of habitat, deforestation, introduction of artificial substances into the environment, overpopulation and encroachment on resources has directly caused the eradication of many species of plants and animal life.