Climate change is blamed for a lot of things. At http://phys.org/print376640171.html … and now is is blamed from the demise of the ichthyosaurs – marine reptiles of the Jurassic. However, a clue lies in that we are told the climate 'changed' – avoiding the question, what caused the climate to change dramatically. Catastrophism may very well be one reason – a catastrophic event of some kind. As far as geochronology is concerned we are told there is a big problem – and the disappearance of the ichthyosaurs occurred before the end of Cretaceous event – by some tens of millions of years. Unlike the land dinosaurs, eliminated as a result of a massive catastrophic impact by an asteroid, the marine dinosaurs died out long before that event. The assumption here is that the Cretaceous is a continuous ongoing record, the various sediments laid down over a long period of time. However, in a Catastrophic interpretation sediments can be laid down quickly, layer upon layer. In other words, the idea that tens of millions of years separates the demise of the ichthyosaurs from the K/T boundary event is all in the head. This doesn't mean the period of time allotted to the Cretaceous is necessary in error – only the timing of the sediments that mark the end of the Cretaceous.