Rodent polyphyly?

Phylogenetic place of guinea pigs: no support of the rodent-polyphyly hypothesis from maximum-likelihood analyses of multiple protein sequences.

Graur et al.'s (1991) hypothesis that the guinea pig-like rodents have an evolutionary origin within mammals that is separate from that of other rodents (the rodent-polyphyly hypothesis) was reexamined by the maximum-likelihood method for protein phylogeny, as well as by the maximum-parsimony and neighbor-joining methods. The overall evidence does not support Graur et al.'s hypothesis, which ra...

Polyphyly of true branching cyanobacteria (Stigonematales).

Cyanobacteria with true branching are classified in Subsection V (formerly order Stigonematales) in the phylum CYANOBACTERIA: They exhibit a high degree of morphological complexity and are known from particular biotopes. Only a few stigonematalean morphotypes have been cultured, and therefore the high variability of morphotypes found in nature is under-represented in culture. Axenic cultures of...

Polyphyly of non-bioluminescent Vibrio fischeri

This study reports the first description and molecular characterization of naturally occurring, nonbioluminescent strains of Vibrio fischeri. These ‘dark’ V. fischeri strains remained non-bioluminescent even after treatment with both autoinducer and aldehyde, substrate additions that typically maximize light production in dim strains of luminous bacteria. Surprisingly, the entire lux locus (eig...

Species polyphyly and mtDNA introgression among three Serrasalmus sister-species.

Polyphyly of gut symbionts in stinkbugs of the family Cydnidae.

Symbiotic bacteria associated with midgut crypts of stinkbugs of the family Cydnidae, representing seven species and 13 populations, were investigated. All of the symbionts were species specific, and constituted at least four distinct lineages in the Gammaproteobacteria, indicating multiple evolutionary origins of the gut symbionts among the burrower bugs.