hard · LSAT Reading Comprehension

In the early twentieth century, ecologists modeled a plant community as a "superorganism" advancing through fixed successional stages toward a stable climax determined by regional climate. Frederic Clements treated the disappearance of pioneer species as analogous to the shedding of an organism's juvenile tissues: a programmed phase in the maturation of a single integrated entity. Henry Gleason demurred. For Gleason, a "community" was merely the coincidental overlap, at one place and time, of species each tracking its own tolerances independently; what looked like an orderly march toward a climax was the statistical residue of countless individual dispersals and deaths, with no collective trajectory at all. The apparent unity of the community, on his view, lay in the eye of the observer, not in any bond among its members. The passage suggests that Clements and Gleason would be most likely to disagree about which one of the following?

1. whether the species composition of a given site changes over time as some species establish themselves and others die out at that location
2. whether regional climate exerts any influence on which plant species are able to persist at a particular site
3. whether the regularities observable in successional change reflect a property of the community as such or merely aggregate the independent fates of its member species
4. whether pioneer species characteristically give way to later-arriving species over the course of succession at many sites
5. whether the methods available to early-twentieth-century ecologists were adequate to detect the boundaries between successive vegetation stages

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