The arrows of evolution: Florentino Ameghino and the laws of Phylogeny

Abstract

The laws stated by the argentine paleontologist Florentino Ameghino (1854-1911) in his work Phylogeny, of 1884, allow understanding of what was involved in the reformulation of the objectives of Natural History of living beings, especially in Paleontology, resulting from the advent of Darwinism. In addition, these laws seem to find their basis in the deepest foundations of evolutionary perspective: although they arise, in fact, from mere empirical generalizations, the laws proposed in Phylogeny seem to find their justification in the assumption that evolutionary processes are always irreversible. They aim to identify paths in the morphospace that can be traversed in one way only, and whose knowledge allows, consequently, to serialize morphological changes. These laws, which are not causal, are laws of succession that, precisely because of the irreversibility of the series they establish, might also deserve the label of ‘historical laws’.