MOLECULAR INNOVATIONS IN LICHEN SYSTEMATICS - THE USE OF RIBOSOMAL AND INTRON NUCLEOTIDE-SEQUENCES IN THE CLADONIA-CHLOROPHAEA COMPLEX

In the mycobiont of the Cladonia chlorophaea complex, length variation in the ribosomal DNA is explained, in part, by the variable occurrenc e of multiple group I introns that may have been mobile during the evo lution of this group. These potentially mobile introns can serve as a model for examining the variation detected in the ribosomal DNA from o ther lichens and, perhaps, as a model for examining variation in other genes, genotypes, and phenotypes. Because group I introns have been f ound also in the ribosomal DNA of some green algae, lichens may provid e a good system to search for evidence of intron transfer between dist antly related organisms. Not only can molecular systematics change the way we look at lichens, but lichens may change the way we look at mol ecular evolution.