Mammalian Evolution & Continental Drift — NEET Biology
📚 Practice ConceptThe first mammals were like shrews. Their fossils are small sized. Mammals were viviparous and protected their unborn young inside the mother's body. Mammals were more intelligent in sensing and avoiding danger at least. When reptiles came down mammals took over this earth. There were in South America mammals resembling horse, hippopotamus, bear, rabbit, etc. Due to continental drift, when South America joined North America, these animals were overridden by North American fauna. Due to the same continental drift pouched mammals of Australia survived because of lack of competition from any other mammal.
Assertion (A): Australian marsupials survived better than marsupials on other continents. Reason (R): Continental drift isolated Australia, and pouched mammals survived due to lack of competition from other mammals.
View solution & NCERT explanation
Correct answer: A — If both assertion and reason are true and the reason is the correct explanation of the assertion.
Both statements are true from NCERT. NCERT states “Due to the same continental drift pouched mammals of Australia survived because of lack of competition from any other mammal.” The Reason explains WHY Australian marsupials survived better - isolation prevented competition from placental mammals that displaced marsupials elsewhere.
What does NCERT say about first mammals were like?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 88 of 90 questions from the NEET 2026 paper were matched straight from the MedicNEET Biology question bank.
88/90MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.