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Fish with specialized teeth for scraping algae occur in both Flower
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05 Oct 2020, 05:43
05 Oct 2020, 05:43
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Fish with specialized teeth for scraping algae occur in both Flower Lake and Blue Lake. Some biologists argue that because such specialized characteristics are rare, fish specifies that have them should be expected to be closely related. If they are closely related, then the algae-scraping specialization evolved only once. But genetic tests show that the two algae-scraping species, although possibly related, are not closely related. Thus, the algae-scraping specialization evolved more than once.
The reasoning in the argument is flawed in that it:
(A) Infers a cause merely from a correlation
(B) Infers that just because the evidence for a particular claim has not yet been confirmed, that the claim is false
(C) Takes a sufficient condition as a necessary one
(D) Infers merely because something was likely to occur that it did occur
(E) Appeals to the authority of biologists who may not be representative of all biologists with expertise in the relevant area
The reasoning in the argument is flawed in that it:
(A) Infers a cause merely from a correlation
(B) Infers that just because the evidence for a particular claim has not yet been confirmed, that the claim is false
(C) Takes a sufficient condition as a necessary one
(D) Infers merely because something was likely to occur that it did occur
(E) Appeals to the authority of biologists who may not be representative of all biologists with expertise in the relevant area
Re: Fish with specialized teeth for scraping algae occur in both Flower
[#permalink]
08 Oct 2020, 06:59
08 Oct 2020, 06:59
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C.
The argument basically states that:
if closely related ---> then evolved once
BUT, reality =>
Not closely related ---> therefore, evolved more than once (i.e. not once)
Its a case of mistaken negation.
(A) Infers a cause merely from a correlation
There is no causality here.
(B) Infers that just because the evidence for a particular claim has not yet been confirmed, that the claim is false
It in fact states that claim(evolved once) is false not because its not confirmed, but because an opposite or counter-evidence has been found.
(C) Takes a sufficient condition as a necessary one
Perfect. Sufficient = closely related. Necessary = Evolved once
(D) Infers merely because something was likely to occur that it did occur
Opposite. It "did not" occur in reality.
(E) Appeals to the authority of biologists who may not be representative of all biologists with expertise in the relevant area
No appeal to authority is done.
The argument basically states that:
if closely related ---> then evolved once
BUT, reality =>
Not closely related ---> therefore, evolved more than once (i.e. not once)
Its a case of mistaken negation.
(A) Infers a cause merely from a correlation
There is no causality here.
(B) Infers that just because the evidence for a particular claim has not yet been confirmed, that the claim is false
It in fact states that claim(evolved once) is false not because its not confirmed, but because an opposite or counter-evidence has been found.
(C) Takes a sufficient condition as a necessary one
Perfect. Sufficient = closely related. Necessary = Evolved once
(D) Infers merely because something was likely to occur that it did occur
Opposite. It "did not" occur in reality.
(E) Appeals to the authority of biologists who may not be representative of all biologists with expertise in the relevant area
No appeal to authority is done.
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Re: Fish with specialized teeth for scraping algae occur in both Flower
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29 Oct 2020, 00:58
29 Oct 2020, 00:58
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nightblade354 wrote:
Fish with specialized teeth for scraping algae occur in both Flower Lake and Blue Lake. Some biologists argue that because such specialized characteristics are rare, fish specifies that have them should be expected to be closely related. If they are closely related, then the algae-scraping specialization evolved only once. But genetic tests show that the two algae-scraping species, although possibly related, are not closely related. Thus, the algae-scraping specialization evolved more than once.
The reasoning in the argument is flawed in that it:
(A) Infers a cause merely from a correlation
(B) Infers that just because the evidence for a particular claim has not yet been confirmed, that the claim is false
(C) Takes a sufficient condition as a necessary one
(D) Infers merely because something was likely to occur that it did occur
(E) Appeals to the authority of biologists who may not be representative of all biologists with expertise in the relevant area
The reasoning in the argument is flawed in that it:
(A) Infers a cause merely from a correlation
(B) Infers that just because the evidence for a particular claim has not yet been confirmed, that the claim is false
(C) Takes a sufficient condition as a necessary one
(D) Infers merely because something was likely to occur that it did occur
(E) Appeals to the authority of biologists who may not be representative of all biologists with expertise in the relevant area
Sufficient condition is when A definitely lead to B, but does not mean that it is the only way to achieve B.
In summary, "If A then B does" not mean "If not A, then not B". (If C , then B can also be true).
Necessary condition is something which works as a prerequisite.
A have to be true for the B to occur. We know that A must have happened if B has happened. 'A' could one of many important factors to be true.
According to the question:
Premise : If A (closely related), then B (evolved once).
Premise 2: Not closely related or just related
Conclusion : If not A (not closely related), then not B (not evolved once or more than once).
Flaw: We are assuming A must take place for B to occur.
Which is what option C says.
