- Discussion: Day 1 Discussion 1 moderator: David Hurst Thomas, AMNH Real Audio Recording David Hurst Thomas: . . . would someone want to just launch into this Russell Graham: I guess I have a question for Paul Martin. I'm still bothered by the idea that we don't find Clovis sites with other extinct taxa. The early arguments in the 1960s is that this was site visibility -- Gary Haynes has alluded ...www.amnh.org/science/biodiversity/extinction/Day1/bytes/d1discussion1.html