As you see, in the opinion of Marx and Engels, revolution is engendered not by Cuvier's "unknown causes," but by very definite and vital social causes called "the development of the productive forces."
As you see, in the opinion of Marx and Engels, revolution comes only when the productive forces have sufficiently matured, and not unexpectedly, as Cuvier thought.
Clearly, there is nothing in common between Cuvier's cataclysms and Marx's dialectical method.
On the other hand, Darwinism repudia