Answer: The correct answer is-
Allopatric- option 2.
Sympatric - option 1.
Allopatric and sympatric are primarily the two major mechanisms for speciation ( formation of new species from an ancestral species).
In allopatric speciation, a population splits into two different species when it is isolated by physical or geographical barrier.
On the other hand, sympatric speciation occurs wihtin the same area. A population splits into two species that is becomes reproductively isolated when a change in the chromosome number occurs.
Thus, option first corresponds to sympatric whereas option second shows allopatric speciaton.
Answer:
The ecological effects of acid rain are most clearly seen in aquatic environments, such as streams, lakes, and marshes where it can be harmful to fish and other wildlife. As it flows through the soil, acidic rain water can leach aluminum from soil clay particles and then flow into streams and lakes
Explanation:
Answer:
At the very bottom
Explanation:
When examining a cross section of rock layers, the oldest layer is on the bottom. This is because over time, newer rock layers continued to form on top of the oldest one.