patto wrote:
As a general rule, the larger a social group of primates, the more time its members spend grooming one another. The main purpose of this social grooming is the maintenance of social cohesion. Furthermore, group size among primates tends to increase proportionally with the size of the neocortex, the seat of higher thought in the brain. Extrapolating upon the relationship between group size and neocortex size, we can infer that early human groups were quite large. But unexpectedly, there is strong evidence that, apart from parents grooming their children, these humans spent virtually no time grooming one another.
Which one of the following, if true, would do most to resolve the apparent discrepancy described above?
(A) Early humans were much more likely to groom themselves than are the members of other primate species.
(B) Early humans developed languages, which provided a more effective way of maintaining social cohesion than social grooming.
(C) Early humans were not as extensively covered with hair as are other primates, and consequently they had less need for social grooming.
(D) While early humans probably lived in large groups, there is strong evidence that they hunted in small groups.
(E) Many types of primates other than humans have fairly large neocortex regions and display frequent social grooming.
First, let us understand what the paradox is:
Social grooming was done to maintain social cohesion. Larger the group of primates more time spent grooming one another. Group size directly proportional to the size of the neocortex.
Hence in humans who have a large neocortex, they should have had large human groups and hence should have spent time on social grooming.
But surprisingly they spent only time on grooming their children not other people in the group. Which is the paradox!
We need to find an answer choice which tells us why they did not spend time in grooming other members of the group? Did they not want social cohesion or did they find other means to attain social cohesion?
Only answer choice B talks about language as a means of social cohesion and helps to answer the above question.
Hence B is the correct answer.