Awe heck, everyone knows that smoking, fatty foods and a strict following of the homosexual agenda killed off the dinosaurs.
And science is always open to new ideas and theories as long as you are willing to test them. And when people start to look it's pretty amazing what they can find. All sorts of theories for the end of the dinosaurs have been tossed out there. Some come out looking more possible, some less. Will we ever be able to know with 100% dead accuracy? Most likely no, but people of reason and rationality are comfortable with that. It's faith and religion (some of them at least) that offer that kind of certainty.
If you look at the theories and research of the DinoNuts, you'll find that there are two schools of thought, both based on climate, but one seeing a gradual and natural change, the other pointing to a catastrophic event ushering in an Ice Age. But they do seem to be in agreement that in some way - due to something - the environment changed in a way that the dinosaurs could not adapt to. Which is in harmony with basic evolutionary thinking, that species that survive and thrive are not necessarily 'the fittest' but those that are the most adaptable and find a niche. While that does discount the Noah and the animals 2x2 story, it's not the radical departure from observable world to find that living things adapt, and those that adapt the best thrive.
And most of atheism in the West is not about the denial of god, but rather a profound doubt about the major stories that have come out of the Bronze Age. I'm down with the Deli Lama (about a lot of things as it turns out), and it seems sensible that if some major tenet is proven to be wrong or in error, then perhaps the wise thing to do is change it. Even the Catholic Church eventually gave into Galileo and his brash claims of a heliocentric solar system- though with it's usual glacial pace it took them quite a few centuries to do it. The pictures from Chandra and Hubble don't prove that god does or does not exist - they do however show us a universe that is much, much, much larger than we thought (and the thinking of average/norm hasn't even begun to come to grips with what those photos show. See: The Hubble Ultra-Deep Field (HUDF)), and the larger the universe is, the less likely it is that whoever, or whatever, created it really wants a personal relationship with you, and it's also highly unlikely that any such entity is sitting in judgement over your sex habits.