fins

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fins

by ansumania » Sun Apr 18, 2010 4:51 pm
Q-Biologist: Many scientists have long believed that the Scottish salmon evolved its distinctive shiny tailfin as a way to confuse its predators by reflecting light from the sun off of its tailfin and into its predators' eyes, causing the predator to become disoriented and lose the fish. New evidence shows that this cannot possibly be the case, as scientists have observed that the shiny tailfin attracts a bird of prey called the Red Wing Hawk through its reflection of the sunlight, which catches the attention of the bird above and causes it to swoop down and devour the fish.

Which of the following, if true, undermines the conclusion above?

A. Red Wing Hawks have only within the past two years started to inhabit any geographical areas in common with the Scottish salmon.

B. Red Wing Hawks are one of many bird species to prey upon the Scottish salmon.

C. The color of the tailfin of the Scottish salmon is nearly the same color as that of a large sea plant very common to the regions in which most of the fish live.

D. The tailfin of the Scottish salmon acts as a decoy which attracts minnows, a main source of food for the fish.

E. Red Wing Hawks fly more slowly in comparison with other birds of prey that primarily prey upon fish.

pl. explain ,

regards,

Ansumania
Source: — Critical Reasoning |

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by liferocks » Sun Apr 18, 2010 5:15 pm
IMO ans is A
A. Since 'Red Wing Hawks have only within the past two years started to inhabit any geographical areas in common with the Scottish salmon' they cannot possibly have any effect on the evolution of the tailfin. So this is undermining the authors conclution that the tailfin is not evolved to confuse the predator of the fish as the Red Wing Hawk uses it to catch them.
B. Irrelevent
C and D. Provide alternate solution for evolution of tailfin other than what is mentioned in first premise ..hence not correct option
E. Irrelevant
what is the OA?

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by reply2spg » Wed Apr 21, 2010 12:53 pm
Please have a look at the inconsistency in blue. It means that Scottish salmon has tailfin for a long time i.e. more than 2 yrs. Red Wing Hawks started to inhibit in areas of fish from last 2 yrs. Therefore, conclusion provided by scientiest is false and this is our answer A
ansumania wrote:Q-Biologist: Many scientists have long believed that the Scottish salmon evolved its distinctive shiny tailfin as a way to confuse its predators by reflecting light from the sun off of its tailfin and into its predators' eyes, causing the predator to become disoriented and lose the fish. New evidence shows that this cannot possibly be the case, as scientists have observed that the shiny tailfin attracts a bird of prey called the Red Wing Hawk through its reflection of the sunlight, which catches the attention of the bird above and causes it to swoop down and devour the fish.

Which of the following, if true, undermines the conclusion above?

A. Red Wing Hawks have only within the past two years started to inhabit any geographical areas in common with the Scottish salmon.

B. Red Wing Hawks are one of many bird species to prey upon the Scottish salmon.

C. The color of the tailfin of the Scottish salmon is nearly the same color as that of a large sea plant very common to the regions in which most of the fish live.

D. The tailfin of the Scottish salmon acts as a decoy which attracts minnows, a main source of food for the fish.

E. Red Wing Hawks fly more slowly in comparison with other birds of prey that primarily prey upon fish.

pl. explain ,

regards,

Ansumania

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by tpr-becky » Wed Apr 21, 2010 10:08 pm
You want an answer that will tell you it can be possible that the fin evolved to disorient predators even though the hawk is attracted to it.

a.if the hawk only recently came into the picture then it is possible that the fin evolved for that purpose. (this is the answer)

b. we don't care about the other species
c. We don't know what it means if it is the same as a plant
d. this is irrelevant and doesn't address the issue of the hawk
e. we need to know about the hawk and the fish, not other birds
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