Bunuel wrote:
Certain groups of Asian snails include both “left-handed” and “right-handed” species, with shells coiling to the left and right, respectively. Some left-handed species have evolved from right-handed ones. Also, researchers found that snail-eating snakes in the same habitat have asymmetrical jaws, allowing them to grasp right-handed snail shells more easily. If these snakes ate more right-handed snails over time, this would have given left-handed snails an evolutionary advantage over right-handed snails, with the left-handed snails eventually becoming a new species. Thus, the snakes' asymmetrical jaws probably helped drive the emergence of the left-handed snail species.
Which of the following would, if true, most strengthen the argument that asymmetrical snake jaws helped drive left-handed snail evolution?
A. In one snake species, the snakes with asymmetrical jaws eat snails, while the snakes with symmetrical jaws do not eat snails.
B. Some species of Asian snails contain either all right-handed snails, or all left-handed snails.
C. Anatomical differences prevent left-handed snails from mating easily with right-handed snails.
D. Some right-handed snails in this habitat have shells with a very narrow opening that helps prevent snakes from extracting the snails from inside their shells.
E. Experiments show that the snail-eating snakes in this habitat fail more often in trying to eat left-handed snails than in trying to eat right-handed snails.
CR32441.01
OG2020 NEW QUESTION
Premises:Snail-eating snakes have asymmetrical jaws, allowing them to grasp right-handed snail shells more easily.
If these snakes ate more right-handed snails over time, this would have given left-handed snails an evolutionary advantage ...
Conclusion:Thus, the snakes' asymmetrical jaws probably helped drive the emergence of the left-handed snail species.
The premises tell us that Snail-eating snakes have asymmetrical jaws so they GRASP right-handed snail shells more easily. So do they end up eating right-handed snail shells more easily, we are not really given. We are given that "if" these snakes ate more right-handed snails over time, then left-handed snails would have an advantage.
Based on this we are concluding that snakes' asymmetrical jaws probably helped drive the emergence of the left-handed snail species.
What will help strengthen it?
A. In one snake species, the snakes with asymmetrical jaws eat snails, while the snakes with symmetrical jaws do not eat snails.We know from the argument itself that in at least some snake species, snail-eating snakes have asymmetrical jaws. This deserves mention only if normal snakes (non snail eating) do not have asymmetrical jaws.
B. Some species of Asian snails contain either all right-handed snails, or all left-handed snails.Irrelevant. We want to strengthen that snakes' asymmetrical jaws probably helped drive the emergence of the left-handed snail species.
C. Anatomical differences prevent left-handed snails from mating easily with right-handed snails.Irrelevant. We want to strengthen that snakes' asymmetrical jaws probably helped drive the emergence of the left-handed snail species.
D. Some right-handed snails in this habitat have shells with a very narrow opening that helps prevent snakes from extracting the snails from inside their shells.This says that snakes cannot eat some right handed snails.
We want to strengthen the opposite case - that snakes' asymmetrical jaws helped them eat more of the right handed snail.
Hence it does not strengthen the conclusion.
E. Experiments show that the snail-eating snakes in this habitat fail more often in trying to eat left-handed snails than in trying to eat right-handed snails.We already know that snakes are able to grasp right handed snails more easily. This option further tells us that snakes are more successful in eating right handed snails. Hence this condition "If these snakes ate more right-handed snails over time" is likely met. Hence, left-handed snails probably had an evolutionary advantage due to the snakes' asymmetrical jaws. We have strengthened our conclusion.
Answer (E)Check another strengthen question discussion here:
https://youtu.be/mB8bm_a4GNk