The reading and listening materials have a heated debate on weather   large pterosaurs were capable of powered flight or whether they were able only to glide. The passage believes so and puts three possible reasons ,yet the lecture opposes them .

First the writer claims that the pterosaurs are cold-blooded ,so they were lack of energy so that they cannot fly ,however the speakers contradicts that pterosaurs had dense like covering which has typically warm-blooded .
second ,the author states that Pterosaurs bones are very heavy thus it donot have efficient time to flight in to the air ,on contracy ,the professor refutes that