 via sort of a complicated web, and they even use this Milankovitch theory to calibrate one of their radioactive dating techniques. On one hand, I guess you could argue maybe it's not that surprising that these dates often seem to agree with one another. So we see that there's a lot of circular reasoning going on, and that gives them an advantage when they're trying to assign ages. But what we're going to see here in the next segment is that contradictions still exist, but you often have to delve into the literature to find them.