At http://phys.org/print362238625.html … changing sea levels and global cooling events caused serious declines in the number of crocodiles inhabiting planet Earth at any given time – which really means that the odd catastrophe has periodically reduced their numbers.
Crocodiles survived the mass wipe out at the K/T boundary 63 million years ago – but just 23 species survive into the modern era. British and US researchers compiled a dataset of the entire known species and surprise surprise they found crocodiles disappeared when temperatures change (as a result of events of some kind). Crocodiles flourished when it became warmer and wetter (tropical and semi tropical) in various parts of the world. Does this imply the tropics have been moving around?
The assumption the researchers seem to take, going by the abstract, is that they are working within the consensus model and that is that the poles are constant, therefore only global temperatures are rising or declining.