The correct Answer is Only three pairs
Explanation
The question assesses knowledge of evidence supporting the theory of Continental Drift, a concept proposed by Alfred Wegener. This theory posits that continents have moved over geological timescales. The evidence includes geological, paleontological, and climatological observations.
Statement-wise Analysis
- Tillite:
- Correct. Tillite is a sedimentary rock formed from glacial deposits. The presence of tillite deposits of the same age across different continents (e.g., India, Africa, Australia, Antarctica) suggests that these landmasses were once contiguous and experienced similar glacial conditions, supporting the idea of a supercontinent (Gondwanaland) and subsequent continental drift.
- Placer Deposits:
- Correct. Placer deposits are accumulations of valuable minerals formed by gravity separation during sedimentary processes. The occurrence of rich gold placer deposits in the Ghana coast, without any corresponding source rock in the immediate vicinity, is explained by the presence of gold-bearing veins in Brazil. This suggests that Ghana and Brazil were once joined, and the gold deposits were part of a continuous geological structure before continental separation.
- Lemuria:
- Correct. Lemuria is a hypothetical land bridge or continent proposed to explain the distribution of lemurs and other organisms across India, Madagascar, and Africa. While the concept of Lemuria as a sunken continent is largely superseded by plate tectonics, it historically represented an attempt to explain biogeographical patterns that are now better understood through continental drift. In the context of evidence for past land connections, it refers to a contiguous landmass linking these regions.
- Mesosaurus:
- Incorrect. Mesosaurus was a small reptile. Its fossils are found only in the shallow freshwater shales of South Africa and Brazil. This limited distribution across two widely separated continents, coupled with its adaptation to shallow freshwater environments (not deep ocean waters), strongly supports the idea that South America and Africa were once connected. If it could cross deep oceans, its fossils would likely be more widespread.
Key Takeaway
Evidence for continental drift includes geological similarities (e.g., tillite, placer deposits), paleontological distributions (e.g., Mesosaurus, Lemuria), and paleoclimatic indicators, all pointing to past connections between currently separated landmasses.