In urodele amphibians like the newt, complete retina and lens regeneration occurs throughout their lives. In contrast, anuran amphibians retain this capacity only in the larval stage and quickly lose it during metamorphosis. It is believed that they are unable to regenerate these tissues after metamorphosis. However, contrary to this generally accepted notion, here we report that both the neura...

As part of a research program on the evolution of somatosensory systems in vertebrates, the dorsal column nucleus (DCN) was studied with (immuno)histochemical and tract-tracing techniques in anurans (the large green frog, Rana perezi, and the clawed toad, Xenopus laevis). The anuran DCN contains some nicotinamide adenine dinucleotide phosphate diaphorase-positive neurons, very little calbindin ...

Chondrocranial development in Ascaphus truei was studied by serial sectioning and graphical reconstruction. Nine stages (21-29; 9-18 mm TL) were examined. Mesodermal cells were distinguished from ectomesenchymal (neural crest derived) cells by retained yolk granules. Ectomesenchymal parts of the chondrocranium include the suprarostrals, pila preoptica, anterior trabecula, and palatoquadrate. Me...

The establishment of exotic invasive species, including plants, has been linked to the decline of some amphibian populations. Of particular concern with invasive plants, from an amphibian conservation perspective, is that they are disproportionately wetland or riparian species. Recent evidence suggests that Chinese tallow (Triadica sebifera), an exotic deciduous tree species, is expanding its r...

Linear transport infrastructure can alter the viability of populations and wildlife passages are used to mitigate their impacts. The assessment outcomes is often limited recording use tunnels by a focal species. For amphibians, effectiveness poorly evaluated with little information about whether certain features encourage individuals that may be reluctant pass through tunnels. One study showed ...

The group of vertebrates on which the present study is based has profoundly influenced, directly or indirectly, the prbgress of the biological sciences. The word-wide distribution and abundance of the group, and the ease with which its members are managed, have made these animals especially useful as laboratory specimens. The present research deals primarily with the diencephalon. Even in such ...

—One of the most fundamental problems in monitoring animal populations is that of imperfect detection. Although imperfect detection can be modeled, studies examining patterns in occurrence often ignore detection and thus fail to properly partition variation in detection from that of occurrence. In this study, we used anuran calling survey data collected on North American Amphibian Monitoring Pr...

the cement gland (cg) is a transient organ, found in most anuran embryos and early larvae and located normally on the front of the head. its sticky secretion allows newly hatched larvae to attach to the egg jelly or to another support later and remain hidden and stationary until feeding starts. our ultrastructural studies showed that prominence structure of the cg in some species exists, but is...