Biology of Amphibians

absent adult Ambystoma ambystomatids amphibians anteriorly anurans aquatic arch articulate associated behavior body bones branchial breeding buccal Bufo bufonids caecilians cartilage cartilaginous catesbeiana cavity cells Ceratobranchial chromosomes cloaca clutches columella dermal distal dorsal Duellman elements Eleutherodactylus embryos feeding female fenestra fibers Figure foam nests forelimb fossil frogs fused genera genus gills glands groups hatching hindlimbs hormones Hyla hylids hyoid hyperoliids innervated inserts larvae lateral leptodactylids males maxilla medial metamorphosis microhylids morphological muscles musculature nasal capsule neotenic nerve neural North America notochord operculum organs ossification otic oviposition oxygen paired Paleocene pectoral girdle pelvic phibians pipids pipiens Plethodon plethodontid salamanders plethodontids ponds posterior posteriorly predators premaxillae presacral prey primitive pterygoid quadrate Rana ranids region reproductive salamanders Salamandra Scaphiopus skin skull species spermatophore stages structure surface tadpoles tail taxa temperature terrestrial eggs tetrapods tion tissue Triturus tropical ventral vertebrae vocal whereas Xenopus Xenopus laevis Zool