August 2,Uppsala University Late Maastrichtian marine assemblage.
The cretaceous period and the aftermath The cretaceous period and the aftermath 6 June Dinosaur The Cretaceous Period and the Aftermath Imagine a great, thickly muscled dinosaur. See those serrated teeth?
And the great yellow eye that is pondering whether you are food or foe? Now, imagine something that can kill this beast and all of its kind. The Cretaceous Tertiary Extinction Event was actually a geologically short period of time.
It is known as the K-T extinction event. The K-T boundary is a thin band of sedimentation found in various parts of the world. The thin band of sedimentation marking the K- T boundary line Did you know that the K stands for Cretaceous period?
The T stands for Tertiary period.
This boundary marks the end of the Mesozoic Era, and it marks the beginning of the Cenozoic era. This was a large scaled mass extinction event. It may have been caused by one or more catastrophes. On March 4,a panel of 41 scientists agreed that the Chicxulub asteroid riggered the mass extinction.
Although, several impact craters such as in the Deccan Traps may have caused it. With such a catastrophic The Chicxulub Crater in Mexico event as this, evolution is sure to occur because of it.
Our understanding of evolution does not depend on our non-understanding of how it began. Right now the scientists believe that complex life cam from simple chemical reactions.
In addition, newly discovered fossil representatives of living groups of birds from the period shortly after the impact appear to have been ground dwellers, based on the proportions of their legs. The Cretaceous Tertiary Extinction event occurred 5 million years ago, and was a geologically short period of time. It was known as the K-T extinction event, and has since become famous. The event is associated with the K-T boundary, which is a thin band of sedimentation found . About 65 million years ago, at the tail end of the Cretaceous period, in a colossal example of what it means to be in the wrong place at the wrong time, a mile-wide asteroid (probably the largest of a series) collided with what is now the Yucatán Peninsula.
Not much is clear about he structure of the first living things and life. Also, there is no scientific consensus on how evolution began. But what we do know is that this event killed the dinosaurs and set evolution in motion.
Evidence of the Deccan Traps on a hillside The Deccan Traps are one of the theories of dinosaur extinction. These were a series of floods that was thought to have been the gradual extinction of the dinosaurs. The Deccan Traps were thought to have lasted over 2 million years.
Recent evidence shows that the traps erupted overyears ago and may have led to the extinction. An artists idea of the cause of dinosaur extinction Another theory is a multiple impact event.
Some evidence of this theory is that the possibility of simultaneous multiple impacts that caused the extinction. Yet another theory is multiple causes. Some could have been volcanism, marine regression, and extraterrestrial impact.
Also, terrestrial and marine communities were stressed. Lastly, the most probable cause of the dinosaur extinction was an impact event. So this is what most scientists think happened. An asteroid hits earth, during the time of K-T boundary. How they know that it was most likely an asteroid is ecause inside of an asteroid is iridium.
Guess what else contains iridium?
|Recommended for you||Flora[ edit ] Although the first representatives of leafy trees and true grasses emerged in the Cretaceous, the flora was still dominated by conifers like Araucaria Here: Modern Araucaria araucana in Chile.|
So then a dust cloud from the asteroid impact blocks the sun for a year or less. This injects sulfuric acid aerosols into the atmosphere. In turn, this inhibits photosynthesis. It takes 10 years for aerosols to dissipate. The aerosols would account for the extinction of plants and phytoplankton.
Then, it would produce high oxygen levels. This supports the intense combustion of he brush and tree. It makes widespread fires, and increases C02 content in the atmosphere.
The wildfire leads to the greenhouse effect, and kills the most vulnerable organisms after impact.It began in the aftermath of the mass extinction event that occurred at the very end of the Cretaceous Period (the so-called K-T boundary), when as much as 80 percent of . acquired trait: A phenotypic characteristic, acquired during growth and development, that is not genetically based and therefore cannot be passed on to the next generation (for example, the large.
About 65 million years ago, at the tail end of the Cretaceous period, in a colossal example of what it means to be in the wrong place at the wrong time, a mile-wide asteroid (probably the largest of a series) collided with what is now the Yucatán Peninsula.
Geologic Time A Brief Synopsis of the Cretaceous Period Prepared by Jamie L. Martinez Introduction The Cretaceous period is part of the Mesozoic Era, and took place approximately 65 to million years ago between the Paleogene period (marking the extinction of Mesozoic mammals) and Jurassic period (age of the dinosaurs).
Apr. 3, — The gradual decline of the dinosaurs and pterosaurs presumably came before the impact of the Chicxulub asteroid and the global mass extinction at the end of the Cretaceous Period. In addition, newly discovered fossil representatives of living groups of birds from the period shortly after the impact appear to have been ground dwellers, based on the proportions of their legs.