UPSC Prelims 2022·CSAT·Reading Comprehension·Passage Comprehension

Natural selection cannot anticipate future environments on the earth. Therefore, the set of existing organisms can never be fully prepared for environmental catastrophes that await life. An outcome of this is the extinction of those species which cannot overcome environmental adversity. This failure to survive, in modern terms, can be attributed to the genomes which are unable to withstand geological vagaries or biological mishaps (infections, diseases and so on). In biological evolution on the earth, extinction of species has been a major feature. The earth may presently have up to ten million species, yet more than 90% of species that have ever lived on the earth are now extinct. Once again, the creationist doctrines fail to satisfactorily address why a divine creator will firstly bother to create millions of species and then allow them to perish. The Darwinian explanation for extinct life is once again simple, elegant and at once convincing- organisms go extinct as a function of environmental or biological assaults for which their inheritance deems them ill- equipped. Therefore, the so- called Darwinian theory of evolution is not a theory at all. Evolution happens- this is a fact. The mechanism of evolution (Darwin proposed natural selection) is amply supported by scientific data. Indeed, to date no single zoological, botanical, geological, paleontological, genetic or physical evidence has refuted either of the central two main Darwinian ideas. If religion is not taken into consideration, Darwinian laws are acceptable just like the laws proposed by Copernicus, Galileo, Newton and Einstein- sets of natural laws that explain natural phenomena in the universe. With reference to the passage, the following assumptions have been made: 1. Only species that have the ability to overcome environmental catastrophes will survive and perpetuate. 2. More than 90% of the species on the earth are in the danger of getting extinct due to drastic changes in the environment. 3. Darwin's theory explains all the natural phenomena. Which of the above assumptions is/are valid?

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  1. A1 onlyCorrect
  2. B1 and 2 only
  3. C3 only
  4. D1, 2 and 3

Explanation

The passage states that "extinction of those species which cannot overcome environmental adversity" occurs. This directly implies that only species with the ability to overcome such challenges will survive and continue, making assumption 1 valid. Assumption 2 is incorrect. The passage mentions that "more than 90% of species that have ever lived on the earth are now extinct." This is a historical fact about past extinctions, not a prediction that 90% of *currently existing* species are in danger of extinction. Assumption 3 is incorrect. The passage says Darwinian laws are "sets of natural laws that explain natural phenomena in the universe," similar to those proposed by other scientists. It does not claim Darwin's theory explains *all* natural phenomena (e.g., it doesn't explain physics or chemistry). It focuses on biological evolution. Therefore, only assumption 1 is valid.
Reading Comprehension: Natural selection cannot anticipate future environments on the earth. Therefore, the set of existing organisms can never

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