Nye stepped onto the stage in front of a hostile audience. It wasn't Nye's first time debating. Since his show on PBS ended in 1998, he has been making speaking tours at colleges and universities. He has also appeared on several cable television programs. It was Ham's home turf. Ham is the head of the museum as well as the Christian outreach organization called Answers in Genesis. He argued the Bible was the ultimate authority on natural history. During the debate, Ham talked about his model of the universe's origins. Nye cited observations from a variety of scientific fields to defend the majority scientific consensus that the Earth is approximately 4.5 billion years old.