GORT KLAATU Posted over 1 year ago As we are programmed to die after a certain period. I believe species are also programmed to die after a certain period. The meteor hypothesis is not the only theory, although it is one that I believe played a part in the dinosaur extinctions. For some reason people look at the meteor strike as a singular event. My theory is that the strike also instigated world-wide volcanic activity. Your first sentence ("There was no competition...") fails to acknowledge that I used the phrase "external forces", which are not restricted to competition and/or fitness issues. A massive meteor strike (and any associated volcanic activity) would certainly qualify as habitat destruction. But that's completely beside the point. If you are suggesting that the dinosaurs all perished because it was their time to expire as a result of some unknown genetic mechanism (an off switch?), that just happened to coincide with a planet-wide catastrophe, then my suggestion to you is the same as yours was to me: "Try thinking differently."