Chapter 23, Problem 1TYU

Which factor most likely caused animals and plants in India to differ greatly from species in nearby southeast Asia?

1. A.    The species became separated by convergent evolution.
2. B.     The climates of the two regions are similar.
3. C.     India is in the process of separating from the rest of Asia.
4. D.    India was a separate continent until 45 million years ago.

Summary Introduction

Introduction:

The Earth is not made up of one compact rock, instead, it is made up of seven different rocks or plates called the tectonic plates. These plates are in a state of continuous movement, but they move at a very slow pace. This property of movement of the continents across the Earth’s surface through the geological time is called continental drift.

Answer to Problem 1TYU

Correct answer:

There was a crash between two of the seven tectonic plates. The Eurasian plate and the Indian plate crashed with each other. It is because of this crash, the formation of the Himalayan mountain system took place. Hence, India was a separate continent until forty-five million years ago. Therefore, the animals and plants of India differ from the species in Southeast Asia. Thus, option (D) is correct.

Explanation of Solution

Reason for the correct statement:

Continental drift is one of the major factors responsible for changes in the formation of mountain eruption of the volcanoes. Mountains affect the climate of a country significantly by blocking wind and air masses. They also cause rainfall in a country. Species from India differ from Southeast Asia because “India was a separate continent until 45 million years ago”.

Option (D) is given as “India was a separate continent until 45 million years ago”.

“The factor that most likely caused animals and plants in India to differ greatly from species in nearby Southeast Asia is that India was a separate continent until 45 million years ago”, hence, it is the right answer.

Hence, option (D) is correct.

Reason for the incorrect statements:

Option (A) is given as “The species became separated by convergent evolution”.

Variations in the animals and plants of India from species in Southeast Asia are because of the Himalayan mountains, and not because the species became separated by a convergent evolution. Hence, it is the wrong answer.

Option (B) is given as “The climates of the two regions are similar”.

There are differences between animals and plants of India from species in Southeast Asia because of the Himalayan mountains and not because of the similarity in the climate. Hence, it is the wrong answer.

Option (C) is given as “India is in the process of separating from the rest of Asia”.

The plants and animals of India differ from their counterparts from Southeast Asia because of the Himalayan mountains and not because India is in the process of separating from the rest of Asia. Hence, it is the wrong answer.

Hence, options (A), (B), and (C) are incorrect.

Conclusion

Continental drift along with the Himalayan mountains are responsible for the difference between the Indian plants and animals from Southeast Asia.