Definition: This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
Input: The Middle Triassic spans from 247 million to 237 million years ago. The Middle Triassic featured the beginnings of the breakup of Pangaea, and the beginning of the Tethys Sea. The ecosystem had recovered from the devastation that was the Great Dying. Phytoplankton, coral, and crustaceans all had recovered, and the reptiles began to get bigger and bigger. New aquatic reptiles evolved such as Ichthyosaurs and Nothosaurs. Meanwhile, on land, Pine forests flourished, bringing along mosquitoes and fruit flies. The first ancient crocodilians evolved, which sparked competition with the large amphibians that had since ruled the freshwater world.
Output:
What is the span of years of the Middle Triassic?