Homology is at the foundation of comparative studies in biology at all levels from genes to
phenotypes. Homology is similarity because of common descent and ancestry, homoplasy is …

Two major skeletal systems—the endoskeleton and exoskeleton—are recognized in
vertebrate evolution. Here, we propose that these two systems are distinguished primarily by …

The evidentiary basis of the currently accepted classification of living amphibians is
discussed and shown not to warrant the degree of authority conferred on it by use and …

This paper presents larval evidence and evaluates its contribution to the discussion of frog
phylogeny; 136 larval characters, 6 reproductive biology characters, and 14 adult …

The morphology of tadpoles has long received too little attention in taxonomic and
phylogenetic contexts, beyond the use of Orton's general tadpole types, despite the potential …

This study analyzes the structure of the mandibular arch musculature in larval, metamorphic,
and postmetamorphic anurans of 26 species and makes comparisons with larvae of three …

The higher-level relationships of anurans have been explored by numerous studies,
producing a variety of hypotheses. The relationships of the basal anurans …

Many male frogs and toads possess sexually dimorphic skin glands (breeding glands).
However, in most anuran species, the functional significance of the glands is unknown. Here …

Hypotheses of relationships are critical to describing and understanding patterns of
evolution within groups of organisms. But rarely has a comparative, historical approach …

Lacustrine interbeds of a volcaniclastic succession that crops out extensively in north-
western Patagonia yielded impressions of articulated, nearly complete, frogs of different …