Ocean dinosaurs and extinction

Hi i was just wondering if much thought has been given to whether if an asteroid hit earth causing dinosaur extinction, why would ALL the sealife die out also? how about dinosaurs( i know im using wrong terminology) that inhabited deep water and plants in deep water also? Even if the sunlight is blocked by debris might not some life survive the depths if not rely on plankton? And what were the species like during the Ice Age in the oceans?

Of course a lot of things survived - on land and in water- otherwise we would not be here. Since such a low percentage of organisms produce fossils we may never know exactly what happened. I suspect that some dinosaurs may well have survived for a time after the extinction event but the climate and environment changed that rapidly they could not survive the rapid evolution that followed in other groups. Only speculation of course but some parts of the world would be less affected.

There is no way the Chixculub impact could have wiped out ALL the dinosaurs, leaving just a few other species to carry on. Undoubtedly almost all life in southern north america and northern south america was annihilated, as was all sea life in the gulf of Mexico and probably a considerable distance into the Atlantic. Probably even some on the Pacific side as well.

But in the rest of the world, dinosaurs soldiered on for a few more years perhaps, only to die out as the climate changed, or food supplies dwindled to nothing. Any large creature would have been in deep trouble. Since there were no large mammals at the time, we don't see the same cutoff in mammal species. Yet there were plenty of small dinosaur species, and one would think that a few of them should have been able to survive well into the Tertiary period. But they did not. Perhaps their eggs could not stand up to the acid rain. Perhaps their diets were too specialized and the impact killed off anything they could eat. Or perhaps a sudden explosion of Mammalian predators wiped them all out. Someday, perhaps, someone will find the fossil of a dinosaur in strata above the K-T boundary, but don't count on it.

John M.

Don't know about the Ice Age, but....

Nearly all