Question

Assertion :From evolutionary point of view, human gestation period is believed to be shortening. Reason: One major evolutionary trend in humans has been the larger head undergoing relatively faster growth rate in the foetal stage.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Both Assertion and Reason are incorrect.

Answer 1

The correct option is D Both Assertion and Reason are incorrect.

Human gestational length has lengthened as compared to other primates, despite the difficulties of that final month. Stephen Jay Gould discusses this in his book Ontogeny and Phylogeny. In brief, despite human's longer gestation period, human brains are far less developed at birth than almost any other mammal, as are bodies, so humans require far more intensive care, for a much longer time, than any other mammal. He hypothesized that well, first, there's the problem of the difficulty of the brain being any larger at birth given the constraints of the human pelvis. And second, exposure to stimuli is so important in the development of the human brain that it's valuable for the brain to develop in an environment much richer in stimuli than the womb.

Therefore, the correct answer is option D.