The Reaction Paper: The sixth extinction: An unnatural history. A&C Black.

The Reaction Paper: The Sixth Extinction Chapter 5
Student’s Name
Institutional Affiliation
The Sixth Extinction
Chapter Five Summary
Chapters five of Elizabeth Kolbert’s “The Sixth Extinction” describes an experiment performed in 1949 to prove the influence of Thomas Kuhn’s thinking on response to the new environment. In this experiment, students misread cards when showed quickly but they recognized their mistakes when the cards were showed slowly. This shows that humans try to adjust to changes in the new environment through the learned coping mechanisms and strategies and eventually learn new strategies (paradigm) for survival. This idea, and subsequently the concept of “paradigm shifts,” provides the perfect lens that can be used to study evolutionary science (Kolbert, 2014, p.47). I the same way, scientists used old rules to try to explain new occurrences. However, nowadays, many scientists believe that extinction of species usually is gradual except in the case of an unexpected, catastrophic event which hastens the process.
Kolbert visits Dob’s Linn cliff in Scottish Highlands where to meet Jan Zalasiewicz, a stratigrapher who shows her some rock layers from 445 million years ago, immediately after dinosaurs’ extinction. It is believed that in the Ordovician era, oceans life that grew at the start of the same period went extinct at the rate of almost 85% (Kolbert, 2014, p.48). Alvarezes’ publish that explained how the asteroid caused dinosaurs to become distinct forced scientists to slowly rethink their antecedents on extinction. They started to believe that other catastrophes could describe other fossil gaps if the asteroid phenomenon could explain a “fossil gap.” In this way, some of them argued that the existence of the minor “companion star” could be used to explain the periodic gaps within their fossil record because they occasionally showered the Earth’s surface with comets that destroyed nearly every life but they were unable to back this thesis up with sufficient empirical evidence.
The current, most shared theory that is used to explain the mass-extinction which occurred at the end of the Ordovician period states that glaciation exterminated most species. This is because the levels of Carbon (IV) Oxide dropped and the temperatures fell in response. Sea levels dropped killing most marine life. Scientists also argue that 252 million years ago, of a possible mass-extinction occurred causing acidity and reducing oxygen in the ocean water and possibly triggering the growth of some poisonous bacteria (Kolbert, 2014, p.51). As a result, many ocean species died, causing a 90% extinction of the world’s species. This insinuates that the mass-extinction differed a little from one another.
While in Scotland, Kolbert learned about giant rats’ theory by Zalasiewicz where he argues that they will reproduce, become huge as well as more powerful. People may oppose this idea but they cannot deny that they have rearranged the ecosystems through their activities and rats follow them whenever they go. Zalasiewicz tries to say that human beings have contributed to a new mass-extinction era, commonly known as the Anthrop...