In the tradition of Descartes, Chomsky and Davidson, rational animals are essentially talking animals. But in the view of Kant, and perhaps Fodor, it is the cognitive capacity for logic that is the essence of human rationality.
One tradition says talking is the essence of rationality; the other says the essence is logic
Robert Hanna (Rationality and Logic [2006], 4.9)
Better an [[egg]] today than a hen tomorrow.