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Early Reptiles and Amphibians
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Gradually, the great swampy coal forests of the Carboniferous period died away and were replaced by vast areas of desert in Permian times. The numbers of amphibians, which needed watery conditions in which to lay their eggs, dwindled. Some became big, dry land animals, but for the most part, the reptiles took over. Reptile eggs were encased in a waterproof shell and could be laid on land.
(A) PLANT EATERS
Some early reptiles became plant-eaters, like Edaphosaurus. Their temperature regulation system, using their great fins, later developed into a mammal's warm-bloodedness.
(B) LAND AMPHIBIANS
Heavy land-living amphibians like Eryops, which had strong legs and jaws, lived at the desert edges.
(C) RULING REPTILES
At the beginning of the Permian period, the reptiles that were to develop into the dinosaurs were small and lizardlike, such as Areoscelis.
(D) FIN BACKS
Dimetrodon also had a large fin on its back. The large surface of the fin enabled it to warm up and cool down quickly.
(E) WATER AMPHIBIANS
Water-based amphibians, like Diplocaulus with its odd-shaped head, still lived in oases.
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Book:
Prehistoric Life
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Section:
Prehistoric
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Chapter:
Early Reptiles and Amphibians
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