Which one of the following, if true, most weakens the author's criticism of the assumption that parasitic interaction...

Antionette on December 10, 2013

Help!

Please explain why E is correct and A incorrect?

1 Reply

Melody on December 16, 2013

We want to weaken the author's criticism of the assumption that parasitic interactions generally evolve toward symbiosis. We can find the author's criticism in lines 45-58. Ultimately, she says that because fungi, both harmful and benign, can now be found both early and late in fungus evolutionary history, "the long-standing evolutionary assumption that parasitic interactions inevitably evolve over time to a greater benignity and eventually to symbiosis so that parasites will not destroy their hosts" (45-50) is overturned.

Answer choice (A) merely strengthens the author's criticism. If "symbiotic interactions generally evolve toward greater parasitism, rather than vice versa," then it is true that "the long-standing evolutionary assumption that parasitic interactions inevitably evolve over time to a greater benignity and eventually to symbiosis so that parasites will not destroy their hosts" (45-50) is false.

Answer choice (E), however, weakens the author's criticism. If the "branches of the fungus family tree that have evolved from symbiosis to parasitism usually die out shortly thereafter," then "the long-standing evolutionary assumption that parasitic interactions inevitably evolve over time to a greater benignity and eventually to symbiosis so that parasites will not destroy their hosts" (45-50) holds strong since those branches that revert towards parasitism are not evolutionarily strong (seeing as they usually die out shortly thereafter).

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