What made niches available for the radiation of: amphibians

These points made niches available for the radiation of amphibians such as:

Step by Step Explanation:

Sooner after they appeared, amphibians are gone through huge adaptive radiation.some were big such as about five meters long.Amphibians become the dominant form of animal life in the swampy warm forest.During the Permian period, the earth's surface and climate change dramatically.The climate becomes less humid and cooler.because of these changes, many of the swamps dried up.these changes made difficult to survive for the amphibians animals.but that was not the case with reptiles.during this time, they began their great period of adaptive radiation.