As early as the twelfth century A.D., the settlements of Chaco Canyon in New Mexico in the American Southwest were notable for their “great houses,” massive stone buildings that contain hundreds of rooms and often stand three or four stories high. Archaeologists have been trying to determine how the buildings were used. While there is still no universally agreed upon explanation, there are three competing theories.
One theory holds that the Chaco structures were purely residential, with each housing hundreds of people. Supporters of this theory have interpreted Chaco great houses as earlier versions of the architecture seen in more recent Southwest societies. In particular, the Chaco houses appear strikingly similar to the large, well-known “apartment buildings” at Taos, New Mexico, in which many people have been living for centuries.
A second theory contends that the Chaco structures were used to store food supplies. One of the main crops of the Chaco people was grain maize, which could be stored for long periods of time without spoiling and could serve as a long-lasting supply of food. The supplies of maize had to be stored somewhere, and the size of the great houses would make them very suitable for the purpose.
A third theory proposes that houses were used as ceremonial centers. Close to one house, called Pueblo Alto, archaeologists identified an enormous mound formed by a pile of old material. Excavations of the mound revealed deposits containing a surprisingly large number of broken pots. This finding has been interpreted as evidence that people gathered at Pueblo Alto for special ceremonies. At the ceremonies, they ate festive meals and then discarded the pots in which the meals had been prepared or served. Such ceremonies have been documented for other Native American cultures.
The passage and the lecture are about the theories of use chaco canyon found in New Maxico. The author states the three theories regarding use of the chaco canyon. The lecturer casts doubt by arging with certain points.
First theory states that chaco canyon were used for residential purpose for around the hundred people as those were large apartment from outside, according to the passage. The lecture opposes this claim by stating that they were large apartment of outside but if there were many people lived then there would have been many fire places. Besides this there were few fire places only.
In Second theory, the passage states that they were used for storage of grains " Grain Maize". On the other hand, the lecture refutes this theory and states that if they were used as storage houses then there should be large containers to store grain maize which were not found on the excavation.
According to third theory mentioned in the passage, the building had been used for ceremonies “Peubo Alto” as they found some evidences of the broken pots. The lectures opposes this by saying that there were not only the broken pot but they also found some raw materials used during building like sand. Furthermore, the lecturer adds that these would have been used for regular trace based on the evidence found under the building.
TOEFL listening discussions: A conversation between a student and a university advisor