>Some life forms were not affected at all, it would appear -- again, why? <
Some friends of mine were discussing this very thing last night, and it would appear to me that the key factor is the ability to go into torpor/hibernate. If you look at what terrestrial animals survived, you have toads/frogs/salamanders/turtles, which I believe can all at least go into torpor, crocs (which can go for a month without food, right?), small mammals (which can go into torpor or true hibernation), and birds (which I heard, I think here, can adjust their metabolic rate). Allan touched on this point a bit ago.
If one wants to take it a bit further, one could use the fact that non-avian dinosaurs died out at the K/T from a bolide as evidence that they were endothermic, but not adapted for torpor/hibernation. If they were ectothermic, from my understanding, it would be easy for them to go for long periods without food. And judging from the survival pattern, if the smaller non-avian dinosaurs were able to go into torpor or hibernate, they may not have gone extinct.
I'm not vouching for the validity of the second idea here, but I just thought it was potentially interesting. However, I do think, as far as my knowledge goes, that the first hypothesis has much truth to it.
Student of Geology
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