Task: Question Answering
Input (English): Background Paragraph: Human beings invented agriculture about 10,000 years ago. This provided a bigger, more dependable food supply. It also allowed people to settle down in villages and cities for the first time. Birth rates went up because there was more food and settled life had other advantages. Death rates also rose because of crowded living conditions and diseases that spread from domestic animals. Because the higher birth rates were matched by higher death rates, the human population continued to grow very slowly. 
Story: Brad studied ancient human settlements from 100,000 years ago. His colleague Phil studied human settlement from 8-10,000 years ago. They were both fascinated by their findings. 
Question: Which colleague did not study that birth rates went up among humans?
Output (English): Brad.