

Share

A hypothetical “nuclear extinction” of the dinosaurs. Images courtesy of Wikimedia Commons; edited by me.

Although an asteroid (or comet) impact event is the prominent theory for the extinction of non-avian dinosaurs 66 million years ago, there are certainly many others. Volcanic activity, climate change, disease, cosmic radiation, and faunal disruption are all credible hypotheses that have been put forward by scientists. However, there are also less credible hypotheses, including cataracts, digestive problems, and arthritis. One of the most bizarre of these fringe theories comes from the muddled world of internet conspiracy theorists. According to proponents of the “ancient alien” mindset, the extinction of the dinosaurs was the result of massive nuclear detonations caused by extraterrestrial lifeforms. Yes, there are some people who genuinely believe that aliens nuked the dinosaurs. They assert that aliens wiped out the dinosaurs in order to further mammal evolution, guiding humanity into existence. Although this is nothing more than absurd speculation, “ancient alien” supporters purport to have actual evidence for this nuclear catastrophe.

Radioactive Fossils



Share

Fossils from the Morrison Formation, like these at Dinosaur National Monument, are known to contain amounts of radioactivity. Image courtesy of Wikimedia Commons.

The ancient alien theorists’ main argument revolves around radioactivity levels in dinosaur fossils. They often claim that dinosaurs near the very end of the Cretaceous contain the highest amount of radioactivity, supposed evidence of nuclear fallout. It is true that many dinosaur fossils contain trace amounts of radioactivity (a topic which has already been discussed here). The fatal flaw of this argument is the fact that the radioactivity did not originate during deposition. The organic material in the bone has been leached away and replaced by minerals, sometimes radioactive ones like uranium and thorium. This occurred over millions of years, not directly after death. Another major problem is that most radioactive fossils are not from the latest Cretaceous. The Chinle and Morrison Formations, which date to the Late Triassic and Late Jurassic respectively, actually produce the most radioactive fossils. This is due to high concentrations of uranium in the soil in Utah, Colorado, and Wyoming, where these formations are located. It is clearly evident that the radioactivity in fossils is not the result of nuclear fallout, but rather of natural concentrations of radioactive elements.

Iridium in the K-Pg Boundary



Share

An exposure of the K-Pg boundary in Colorado. Image courtesy of National Geographic.

Ancient alien supporters also maintain that the high levels of iridium in the Cretaceous-Paleogene (K-Pg) boundary are evidence of a nuclear cataclysm. According to them, iridium is a common indicator of nuclear blast sites. Once again, this is based in truth; the whitish clay layer of the K-Pg boundary (seen in the photo above) does contain over 1,000 times the normal concentration of iridium. However, the iridium found in the clay layer consists of the two naturally occurring, non-radioactive isotopes, iridium-191 and iridium-193. These two isotopes are relatively rare on earth, but are more commonly found in meteorites. There are 34 radioactive isotopes of iridium, none of which are naturally occurring. The most stable of these is iridium-192, which is produced in a nuclear reactor and is used mainly for radiation therapy, but is not a component of nuclear weapons. Thus, the ancient alien theorists are wrong on two accounts - the iridium in the K-Pg boundary is natural and non-radioactive, and artificially-created radioactive iridium is not even used in nuclear weapons.

Other “Evidence”



Share

An estimated map of the Chicxulub Crater. Image courtesy of The Yucatan Times.

The Chicxulub Crater in the Yucatán Peninsula of Mexico is seen by the majority of the scientific community as an indication of an asteroid (or comet) impact. However, the ancient alien adherents believe that it is instead a massive nuclear blast crater. Taking into consideration that the Chicxulub Crater is around 180 kilometers (110 miles) wide and 20 kilometers (12 miles deep), it would have taken an explosion 2 million times more powerful than the largest yield nuclear device ever tested. This is easily feasible for an impactor with an estimated diameter of 10 kilometers (6 miles), but is impossible for any nuclear weapons.

Another claim is that dinosaur fossils are scattered and disarticulated because of the shock waves from nuclear blasts. The ancient alien supporters point to Late Cretaceous bonebeds like those at Dinosaur Provincial Park and Prince Creek as evidence. These bonebeds are known to have been deposited by fast-flowing rivers, which accounts for the jumbled nature of the fossils. Additionally, there are numerous similar bonebeds known from other time periods, including Ghost Ranch from the Late Triassic and Dinosaur National Monument from the Late Jurassic. These large bonebeds are the result of environmental factors, not nuclear shock waves.

Conclusion:

Unfortunately, this “theory’ (the term is used loosely) is not as dead as some of the others featured in this series. Conspiracy websites like theflatearthsociety.org, perpendicularity.org, and ancientnuclearwar.com have entire pages dedicated to it. It was even featured on an episode of History Channel’s notorious Ancient Aliens, appropriately titled “Aliens and Dinosaurs”. It is severely distressing that something so outlandish has been assumed and actually accepted by people. Ancient alien theorists will claim that extraterrestrials were responsible for nearly everything in order to build more “evidence” for their delusional argument. There is none of this evidence in the K-Pg extinction event, nor anywhere else. In the simplest terms, famed astronomer Carl Sagan put it best -

“Extraordinary claims require extraordinary evidence.”

Previous: Fire-Breathing Parasaurolophus and Sauropods with Trunks

Next: The “Dinosauroid” and Tetrapteryx

Carnoferox is a champion moderator and an all time top contributor at Dinosaur Home.