Nearly 75% of plant and animal species on Earth, including all non-bird dinosaurs, went extinct during the Cretaceous-Paleogene (or Cretaceous-Tertiary) extinction event. Scientists have spent years speculating about what precipitated this extinction. Various hypotheses have been presented to account for the disappearance of these huge creatures. The prevailing theory is that a large asteroid collided with Earth and its impact raised a cloud of dust that prevented sunlight from reaching the planet's surface for many years. Temperatures fell rapidly, and without sunlight, much of the plant life on the planet's surface disappeared. Without warmth or food, the dinosaurs, as well as many other species, became extinct.
In support of this theory, scientists have found a thin layer of sediment in marine and terrestrial rocks that contains metals that are rare on Earth but abundant in asteroids. Additionally, a large crater was found in the Gulf of Mexico that must have been formed when an asteroid hit Earth at roughly the same time as the extinctions took place.
Amid the destruction was opportunity for evolution. There were countless vacated ecological niches and the surviving organisms rapidly adapted and developed in order to occupy these niches. It is believed that several of the mammals, including primates, that are alive today developed during this time.
If Charles Darwin read this passage, would he agree with the statements made in the last paragraph?

C. Yes. Darwin believed that slight differences between organisms can be selected for through natural selection and that this would be exacerbated in a time when there were many potential ecological niches.


Darwin would very likely agree with this passage because of his belief in natural selection and the conditions under which it occurs. Moreover, he did not believe in destiny - so eliminate (A) - or consider tragedy in his theory, so eliminate (B). Choice (C) closely describes Darwin's views - (C) is correct - while (D) implies that evolution took place at the level of individual organisms, a common misconception about Darwin's theory, which described species and populations but not individuals. Eliminate (D).

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