TPO39 Integrated Task

The reading and the lecture are both about the theories that explain the mass extinction at the end of the Triassic period about two hundred million years ago. Whereas the author of the reading states that there are some theories that can explain the destruction of many species at that time, the lecturer suggests that none of these theories can be a good explanation of the extinction. The lecturer casts doubt on the main points made in the reading by providing three reasons.
First of all, according to the reading, near the end of the Triassic period, sea levels declined and due to this, the habitats for the species that live in shallow and land were destroyed. Therefore, food chains were negatively affected in the whole world. However, the lecturer disputes this point. She says that it is true that the sea levels were fluctuating at that time but it should be mentioned that the coastal and ocean species have an adapting behavior. thus, if the fluctuation occurs gradually, they can adapt themselves easily and that sea level declination was gradual enough, so it can not be the reason for mass extinction.
Secondly, the reading states that the widespread volcanic activity released a huge amount of sulfur dioxide, cause climate cooling and as a result the distinction. Nevertheless, the lecturer refutes this argument. She argues that it is obvious that the sulfur dioxide can make the weather cool but it should be present in the atmosphere for a long time to cause that negative effect on the plants and animals mentioned in the reading. But the sulfur dioxide will combine with water and do not remain in the atmosphere, so this theory does not work for the distinction explanation.
Finally, the reading claims that the asteroid collision to the earth makes the soil and crushed rocks to throw up to the atmosphere and block the sunlight came to earth. On the other hand, the lecturer believes that it is acceptable that there was an asteroid collision to the earth but it occurred about twelve million years before the extinction. Therefore, the collision can not have an impact on extinction.