Quote:
In humans, the pilomotor reflex leads to the response commonly known as goose bumps, and this response is widely considered to be vestigial—that is, something formerly having a greater physiological advantage than at present. It occurs when the tiny muscle at the base of a hair follicle contracts, pulling the hair upright. In animals with feathers, fur, or quills, this creates a layer of insulating warm air or a reason for predators to think twice before attacking. But human hair is too puny to serve these functions. Goose bumps in humans may, however, have acquired a new role. Like flushing—another thermoregulatory (heat-regulating) mechanism—goose bumps have become linked with emotional responses, notably fear, rage, or the pleasure of, say, listening to beautiful music. They may thus serve as a signal to others.
In explaining the “new role” (line 7) that goose bumps in humans may have acquired, the author assumes which of the following?
A Emotional responses in humans
can be triggered by thermoregulatory mechanisms.
We know that these two-emotional responses and thermoregulatory mechanisms- are linked but nothing in the argument tells us that one triggers the other or vice-versa. Hence, incorrect.
B The perceptibility of emotional responses to other humans offers some kind of benefit.
Towards the end of the argument, the words 'new role' have been used in the premise and 'may thus serve as a signal to others' have been used as part of the conclusion, but without stating if the role being served is- beneficial or detrimental? or if the signals being sent out are- Good or bad?
The argument starts by mentioning about 'something formerly having a greater physiological advantage than at present' relating to goose bumps. This first sentence is what helps us put the pieces together and conclude that the argument is about the beneficial role of goose bumps.
C If human hair were more substantial, goose bumps
would not have acquired a new role.
It is a bit of a stretch to say that human hair would not have acquired a new role. What if they were substantial but were need to fulfill another purpose. This option does create some confusion but the certainty of 'would not have' is far fetched. The phrase 'might not have' would have been more more apt.
D Goose bumps in animals with feathers, fur, or quills may also be linked to emotional responses.
Option D
does not address the premise which deals with the '
new role' or the conclusion- 'may serve as a signal to others'.
E In humans, goose bumps represent an older physiological response than flushing.
No data provided about the two. Also,
negating does not undermine the argument. Being an older or newer physiological response does not link to the 'new role'. Just the 'role' is new, not the existence of the response itself. We can't compare the two based on the info provided in the stimulus.
Answer option B.