Coevolution: Biological observations from Yucca moths to molecules, an introduction

Mutualisms between plants and animals have been observed since the nineteen th century with George Engelmann's 1872 note of the nocturnal visits of yuc ca moths to Yucca. Not until 1964 were such close ecological associations t ermed "coevolution" by Ehrlich and Raven. Since then, these mutualistic rel ationships have been seen to extend beyond plant-pollinator interactions. E xamples are now known to occur between fungi and flowering plants, among ma rine algae, and even for the enteric bacteria of phloem-feeding insects. Th e 46th Annual Systematics Symposium held at the Missouri Botanical Garden i n 1999 presented modern coevolution research using methodologies moving fro m field observation into molecular analysis.