Dinosaur Extinction

Dinosaur track
Dinosaur track | Source

There is still no definite explanation as to why dinosaurs disappeared. But scientists have been arguing on several theories on the possibilities of what might have occurred. One thing is for sure, dinosaurs became extinct at the end of the cretaceous period about 65 million years ago and fossils and rock formation is continuously being studied by paleontologists to solve or shed light to this issue.

Asteroid Theory

A widely accepted explanation is the Asteroid theory proposed by the team of Luis and Walter Alvarez. It suggests that a huge asteroid—almost a mile in diameter, hit the earth and the resulting impact caused an enormous explosion. The outcome of which threw dust clouds in the sky that surrounded the earth in darkness; massive forest fires triggered by the heat would add smoke to the sky, darkening the planet even more. Findings of the Scientists at the Southwest Research Institute in Boulder, Colorado confirmed this theory after tracing the path of that asteroid back into space. According to their calculations 160 million years ago a collision between Baptistina , the 100-mile-wide asteroid and a smaller asteroid outside the orbit of Mars, shattered the larger asteroid and sent pieces of it into the inner solar system. After 95 million years these pieces came in contact to the earth that ended dinosaurs' reign (Krystek 2008).light to this issue.

Volcano-Greenhouse Theory

Another theory that could explain the extinction of dinosaurs was proposed by Dewy McLean is the Volcano-Greenhouse Theory. McLean suggested that rapid eruption of vast Deccan Traps lava fields-- a hotspot volcano on Reunion Island in the Indian Ocean about 700 km east of Madagascar; flooded the earth’s surface with overwhelming amount of carbon dioxide, it is considered as one of the greatest volcanic eruption in earth history. The duration of the volcanic eruption is the same with major shifts in the carbon cycle. This subsequently caused greenhouse warming and chemical changes in the ocean that caused mass extinction including dinosaurs.


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Dinosaur as Presented in Movies

Bug/ Disease theory

The third theory that could explain the disappearance of dinosaurs is the Bug/ Disease theory by George Poinar. This theory suggests that disease-carrying insects rapidly expanded during the late cretaceous era, many of which carry new diseases. Poinar explains that the increase in temperature and evolution of flowering plants in the late cretaceous era contributed to make a perfect condition for an explosion in the number of disease-carrying insects. The dinosaurs have little resistance to the new diseases declined in population (Krystek 2008).

Double Whammy Theory

Lastly, the Double Whammy theory by Professor Arens. She argued that, dinosaurs became extinct because of a series of events and not just a single phenomenon. In addition, the earth has experienced several traumatic events over history, it’s on this periods that extinction rate soars up. In the case of the dinosaurs, a combination of massive volcanic eruptions meteor/ asteroid impacts were taking place hitting life on earth with a "double whammy" (Ibid.)

Other theories would suggest that dinosaurs became extinct because of food chain imbalance, ice age, gradual changes in temperature, and adaptation failure. Same paleontology data often times would yield different conclusion. One thing is for sure, additional researches are needed to fully explain as to why dinosaur became extinct. Collective paleontological findings and general study and calculation would be helpful to truly understand as to what caused their disappearance.

Reference

Krystek, Lee. Who Dunnit to the Dinosaurs? Museum of Unnatural Mystery. 2008. <http://unmuseum.mus.pa.us/deaddino.html>

McLean, Dewey M.The Deccan Traps Volcanism-Greenhouse Dinosaur Extinction Theory. Dewey M. McLean. 1995. <http://filebox.vt.edu/artsci/geology/mclean/Dinosaur_Volcano_Extinction/pages/studentv.html> 17 July 2009.

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Comments 7 comments

Charles Weber 2 years ago

The Cretaceous ocean predators were very large. I suspect that the productivity implied by this was caused by a flow of phosphorus toward the ocean from the savannas (seasonal rainfall areas) permitted by erosion of phosphorus rich runways of plant smothering termites in the Amitermitinae starting in late Jurassic in Australia where the first ocean phosphorite deposits occurred. Anoxic conditions in the oceans were also probably caused by this. This anoxic bottom condition probably helped reduce the ammonites also, in addition to competition from phosphorus enhanced vertebrates. The savanna herbivore dinosaurs declined in armor, teeth, and quite a bit in bony structure across the Cretaceous outside of South America, especially in southeast Asia. Many even lost teeth. I suggest it was due to this same phosphorus famine created by erosion of the soil of the runways of plant smothering termites. Pterosaurs and birds probably lost teeth primarily because of the young eating iron oxide and bauxite in the flying reproductive soil borne termites’ guts, which bound the phosphates. You may see this discussed in more detail starting in http://www.angelfire.com/nc/isoptera/termites.html and its links, which links explore the possible affect that ant evolution had upon them. By the time the Cretaceous ended the world ended up with tiny savanna vertebrates, most of them mammals, which were able to give their young phosphorus in milk at that critical stage. They were a far cry from the massive, well boned Stegosaurs, etc., which roamed around the Jurassic, and had diminished tooth structure at first. They were a long time starting to increase in size (several million years).

You may see the affects on soil discussed in more detail in http://www.angelfire.com/nc/isoptera/soil.html .

Sincerely, Charles Weber

PS It is conceivable that you would also find interesting a hypothesis of my son explaining the Decca (or Deccan) lava flows as disruption of the crust by the disruption of the crust at the antipode (opposite side of a sphere) by a huge meteorite impact. You may see my version in http://charles_w.tripod.com/antipode.html .

Sincerely, Charles Weber


jawad 4 years ago

i think an asteroid crashed into the earth, set of the deccan traps in india, sent ash and carbon dioxide clouds into the air which stops sunlight for almost a year, the deccan traps trigger earthquakes which causes tsunamies for all the dinosaurs that lived on islands that would destroy all the dinosaurs except for the mammals that could find burrows under ground.

personally i don't think the dinosaurs are extinct i think they are still alive but little in population in the Bermuda triangle

excellent hub though


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lone77star 5 years ago from Cebu, Philippines

I suspect that it's a combination of all of the above.

Likely the meteor impacts were the major catalyst. The Deccan Traps? What caused them? Meteor impacts?

Dinos dying from the climate change gave rise to an abundance of festering mounds of decaying, rotting, disease-ridden flesh ripe for bugs to transfer around the world.

Excellent Hub!

Thanks!


lee custodio profile image

lee custodio 5 years ago Author

thanks Will, my avid reader! ^^


WillStarr profile image

WillStarr 5 years ago from Phoenix, Arizona

Excellent Hub!


lee custodio profile image

lee custodio 5 years ago Author

thanks Jack! :)


Apostle Jack profile image

Apostle Jack 5 years ago from Atlanta Ga

Great hub.

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