The study of cactus evolution: The pre-DNA era

Abstract

We provide a short history of the development of phylogenetic concepts for the cactus family in the pre-molecular (here meaning pre-DNA) era, beginning from the creation of the first artificial classification systems, over to natural systems, and on to the progress made in the Post-Darwinian era. Although several authors have presented their ideas on the evolution of Cactaceae, it was the botanists Alwin Berger and Franz Buxbaum who made the most essential contributions towards a cactus phylogeny during the 20th century. In the second half of that century, new techniques and detailed studies (phytochemistry, anatomy, SEM) helped formulate new concepts or revised established concepts about the evolution of cacti.