While the reading believed that dinosaurs such as the elephant-sized edmontosaur survived the tough winter by migrating south to more hospitable regions, the professor, on the other hand, totally disagree with the idea by giving three following reasons.

In contrast to the reading ,which claims that the edmontosaur was fed on plants , those would not grow during the cold and dark night ; the lecturer states that evidence is not convincing since the weather in Alaska's North Slope at that time is much warmer than today and the sun shines twenty-four hours a day in the summer, it would be an incredible ideal place for plants to grow. Even those plants would die in the winter, the dead part which had become the nutrition will provide adequate food for them.

Although the author of the reading claims that the amount of skeletons buried together showed that edmontosaurs lived inb herd, the professor counters that argument by asserting that living in herd may due to many other reasons such as protecting themselves from the predators. He also provide a extra example of animal which live in herd but do not migrate.

The reading passage states that edmonosaurs were physically capable of migrating long distances; however, the lecturer insists that the young dinosaurs unlike the adult ones, are not physical capable and they might even not made it to the destination. Therefore, the adults will have no choice but to stay with them in order to make sure they will survive the cold winter.