summary of sex, drug, disasters and the extinction of dinosa

A Summary of Sex, Drugs, Disasters, and the

Extinction of Dinosaurs

Student ID 20130301188 Student Name Chen Yanxin (Gloria) SchoolSchool of English for International Business Major Business English (International Business Management) Advisor Jonathan Ellman DateApril4, 2016

A Summary of Sex, Drugs, Disasters, and the Extinction of Dinosaurs

At the beginning of this essay, the author Stephen J. Gould clearly states his opinionthat the essence of science lies in the fruitful inquiry and the methods to develop and defend certain claims instead of the sole conclusion. In order to further support his idea, Gould makes a contrast between testable proposals and useless speculation. Scientific proposals are expansive, offering new suggestions and implications in broader fields. In contrast, useless speculations are restrictive. They provide no testable hypothesis and lead to nowhere.

Later, he discusses three famous theories on the explanation of dinosaur extinction: testicular malfunction theory, overdose theory and asteroidal zapping theory. The mass dying of dinosaursdidn’t fall into normal extinction cycles in the history and many other creatures (e.g. plankton and invertebrates) died with geological suddenness at the same time. Therefore, Gould argues that it makes little sense for speculations to limit todinosaurs alone.

The testicular malfunction theory suggests that high temperaturebefore the Cretaceous extinction sterilized all male dinosaurs. Basing on Galileo’s volume-surface ratio theory, scientists argued that larger animals with relatively smaller surface were less able to shed excess heat. They studied the body temperature fluctuation of alligators and extrapolated up to ordinary adult dinosaurs. They guessed temperature rose beyond dinosaurs’tolerance and therefore malfunctioned their testes.The psychoactive

overdosing theory gained supportfrom Siegel who claimed to have collected 2000 records of animals’ drug taking. He suggested that flowering plantswhich produced alkaloidsevolved at the end of Cretaceous. Sincedinosaurs could neither tasted the bitterness of the plants nor detoxify them with livers, they died from overtaking the drugs. He believed that contorted dinosaur fossils also prove this theory. The asteroidal zapping theory proposed that an asteroid struck the earth, whose impact generates blowing particles. They later gathered and formed a gigantic dust cloud, tightly enveloping the earth. As a result, photosynthesis ceased and temperature dropped sharply. Dinosaurs were killed by starvation and freezing.

Gould then explains why the first two theories are useless speculations while the third one represents expansive science. Testability is the first criterion: both testicles and livers of dinosaurs don’t fossilize. What’s more, there is no evidence to prove the optimal temperatures for dinosaurs. The overdose theory fails to explain the extinction of other creatures such as plankton. Strata movement can better explain the contorted fossils.As for the third theory, the discovery of massive increase of iridium serves as testable evidence. Expansiveness is the second criterion. The first two theories led to nowhere after proposed; they cannot be refined or extended or refuted. The impact hypothesis, on contrast, spawned many studies and new findings (e.g. isotopes-marked spherules). One important extension of the theory is that it helped rivet the “nuclear winter”, which argues that nuclear exchange may cause a similar catastrophe that will wipe out human beings.

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