Self-study
Ornithologist: The curvature of the claws of modern tree-dwelling birds enables them to perch in trees. ███ █████ ██ █████████████ ███ ████████ █████ ████████ █████████ ████ ███████ █████████ ████ ████ ████ ███████ ███ ████████ ██ █████ ██ ████ ██████ ██████████ ████████████ ███ ████████ █ █████████████ █████████
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Summarize Argument: Counter-Position
The ornithologist points out that the curvature of the claws of modern tree-dwelling birds is what allows them to perch in trees, and Archeopteryx's claws had a similar curvature. The ornithologist concludes that Archeopteryx was a tree-dwelling creature. The paleontologist counters that claw curvature alone is not sufficient to show that Archeopteryx was tree-dwelling. As evidence, the paleontologist points to the case of chickens, which spend time perched in trees and so also have curved claws, but are primarily ground-dwelling birds.
Describe Method of Reasoning
The ornithologist's argument is an argument by analogy: the ornithologist points out a similarity between modern tree-dwelling birds and Archeopteryx to conclude that Archeopteryx was also tree-dwelling. The paleontologist undermines this conclusion by pointing out another case--chickens--that share the same trait and so fit the analogy, but do not support the ornithologist's conclusion. Chickens are able to perch in trees, implying they also have curved claws, but they are ground-dwelling. Thus, the paleontologist uses this example to show how the ornithologist's argument, which is based on the similarity of claw curvature alone, isn't enough to establish that Archeopteryx was tree-dwelling.
8.
In responding to the ornithologist's ██████████ ████ ████████████ ███ ██████████████ ███ ██████████████
a
questions the qualifications ██ ███ █████████████ ██ ████████ ███ ████████
The paleontologist never mentions the ornithologist’s qualifications. Rather, the paleontologist questions whether the ornithologist’s evidence is sufficient, based on the example of a modern bird.
b
denies the truth ██ ███ ██████ ███ █████████████ █████ ██ ███████ ██ ███ ██████████
The paleontologist does not deny that curved claws enable birds to perch in trees, nor does he deny that Archeopteryx also had curved claws and could perch in trees. He just denies that this evidence is enough to show that Archeopteryx was a tree-dwelling bird.
c
uses a parallel ████ ██ ██████████ █ ████████ ██ ███ ███████████████ ████████
This accurately describes the paleontologist's argument. The parallel case the paleontologist uses is the case of chickens, which can also perch in trees--implying they have curved claws--but are primarily ground-dwelling birds. The paleontologist uses this example to undermine the ornithologist's assumption that the claw curvature shared between modern tree-dwelling birds and Archeopteryx is enough to establish that Archeopteryx was a tree-dwelling bird. Chickens also share this trait of curved claws, but aren't tree-dwelling.
d
shows that the ██████████ ███████████ ███ ██ ███ ██████ ██ ████████ ████ ██ ███████ ██
The paleontologist does not claim that the ornithologist’s hypothesis contradicts the evidence offered in support of it. Rather, the paleontologist claims that the ornithologist’s evidence is not sufficient to support the hypothesis: the fact that modern tree-dwelling birds have curved claws, and Archeopteryx also had curved claws, isn't enough to establish that Archeopteryx was tree-dwelling.
e
provides additional evidence ██ ███████ ███ ███████████████ ████████
The paleontologist does not support the ornithologist’s argument. The evidence the paleontologist provides--the example of chickens--is not meant to support the ornithologist's conclusion, but to show that the ornithologist’s evidence isn't sufficient to support that conclusion.