Controversies in Science/What killed the dinosaurs/A Critique of The Extinction of the Dinosaurs in North America

(Review Paper) Cited in Controversies in Science/What killed the dinosaurs/A Critique of The Extinction of the Dinosaurs in North America

Points Made

Thermal stress from an intense infrared radiation pulse may have resulted in the global wildfires which would have incinerated anything that was not sheltered during the event. This pulse may have been caused by a meteor or asteroid, however whether or not it was the factor or just one of many factors we are currently unable to state. While marine regression would contribute to the extinction of life along coastal regions, this cannot be attributed to the extinction of the dinosaurs due to as these events would have taken place over a million or so years. The asteroid event would have resulted in this regression but would not have been significant enough to eliminate the dinosaurs. Another factor of the extinction of the dinosaurs would be the dust from the meteorite covering the sun. This led to extinction of the plants due to low access to sunlight to create photosynthesis, which led to a domino effect in the food chain starting with the smallest organisms of life and ending with the biggest.

Methods

Researchers were able to chart the extinction rates by using date charting techniques to determine when each individual organism died

Results

The authors concluded that while the actual cause of the extinction can not yet be known, in part due to an inconsistent and inconvenient geological and fossil record, the evidence for a quick (10,000yr) extinction due to extreme climate change exists. The main question being whether or not an asteroid caused or significantly contributed to said change. Migratory records seem to support the asteroid hypothesis if you assume the impact aerosolized the ground it struck, ejecting it into the atmosphere and emitting a giant infrared burst that would have caused global wildfires, but the kill mechanism remains unknown.

Three separate research groups utilizing three different methods have developed strati-graphic quantifiable data regarding the dinosaur extinction in western North America regarding the late Cretaceous period. These studies indicated that the decline in the variance of the dinosaur population demonstrates an instantaneous geological event.