Passage Summary: Some researchers claim we have no proof that animals are going extinct at an increasing speed. The author disagrees, pointing out that for North American fish, the number of extinctions in the late 20th century was more than double the number from the first half of the century.

Conclusion: The assertion that there is no evidence to support the idea that the rate of animal species extinction is currently accelerating is incorrect.

Reasoning: The author provides specific data on North American fishes, noting that while 13 species or subspecies vanished between 1900 and 1950, that number jumped to 27 between 1950 and the end of the century.

Analysis: To identify the conclusion here, look for the author’s pivot away from the 'recent article.' The phrase 'They are wrong, however' serves as the primary claim, signaling that the author's main goal is to refute the previous statement. In LSAT logic, when an author introduces someone else's opinion only to dismiss it, that dismissal is almost always the main point. The specific statistics regarding North American fishes are premises provided to support this dismissal, rather than the conclusion itself.