Topic
Caudata
About: Caudata is a research topic. Over the lifetime, 407 publications have been published within this topic receiving 12190 citations. The topic is also known as: salamanders.
Papers published on a yearly basis
1 / 2
Papers
TL;DR: It is suggested that old-field habitats offer greater landscape resistance to dispersing juveniles of some species, and forest fragmentation is likely to reduce dispersal rates between local populations of these three species, with potentially negative consequences for population persistence in altered landscapes.
Abstract: We used an experimental approach to investigate the effects of landscape composition on the initial dispersal success of juvenile amphibians. Larval amphibians—spotted salamander (Ambystoma maculatum), small-mouthed salamander (A. texanum), and American toad ( Bufo americanus )—were added to artificial pools in four dispersal arrays on forest edges. Each array consisted of a pool surrounded by a circular drift fence with pitfall traps and two 2.5 × 50 m enclosures (runs) extending into forest and old-field habitat. Juveniles captured at the circular fences were individually marked and released into either field or forest runs. We determined initial distance, initial rate, total distance, and net distance moved by juveniles in the field versus forest from recaptures in the runs. We also conducted 24-hour dehydration trials to compare the rates of evaporative water loss by spotted and small-mouthed salamanders in field and forest. Initial orientation of spotted salamanders and toads was significantly biased toward forest. Orientation of small-mouthed salamanders did not differ significantly from random expectations. The avoidance of open-canopy habitat by juvenile American toads in particular indicates that predictions of dispersal behavior based on adult habitat use may be misleading. Spotted salamanders moved almost four times farther and toads more than three times farther into the forest than into the field, and recapture rates of both species were much lower in the field. We attribute the lower recapture rates and shorter distances moved in the field to higher mortality due to desiccation or an abundance of predators. Juvenile spotted and small-mouthed salamanders experienced greater evaporative water loss in the field. Our data on movement behavior and dehydration rates suggest that old-field habitats offer greater landscape resistance to dispersing juveniles of some species. Thus, forest fragmentation is likely to reduce dispersal rates between local populations of these three species, with potentially negative consequences for population persistence in altered landscapes.
401 citations
TL;DR: Tests of different crown topologies show that placement of amphibians within lepospondyls is not a significantly worse fit for the whole character set than a close temnospondyl‐lissamphibian relationship, and the latter phylogenetic hypothesis best captures the most coherent assembly of derived lissampshibian apomorphies.
Abstract: Synopsis Extant amphibians consist of Salientia (frogs), Caudata (salamanders), and Gymnophiona (caecilians). The mutual relationships of these groups are controversial, with either Batrachia (Salientia + Caudata) or Procera (Gymnophiona + Caudata) as emerging clades in recent molecular and morphological analyses. The monophyly of amphibians as a whole is supported by independent data, but their origins and affinities with early tetrapods are debated. A new cladistic analysis of early tetrapods retrieves Temnospondyli (the most species‐rich group of early tetrapods) as the closest relatives of crown group amphibians. One temnospondyl group, the Dissorophoidea, forms a series of consecutive outgroups to crown amphibians. In particular, the Lower Permian amphibamid Doleserpeton is the most derived plesion on the amphibian stem. The Albanerpetontidae, a group of salamander‐like tetrapods ranging from the Jurassic to the Pliocene, are placed as stem Gymnophiona. The shortest trees support the Batrachia hypoth...
225 citations
TL;DR: It is concluded that Bergmann's rule is not generally applicable to these taxa, and evolutionary explanations of Bergman's clines in other tetrapods need not account for unique life-history attributes of amphibians.
Abstract: The tendency for organisms to be larger in cooler climates (Bergmann's rule) is widely observed in endotherms, and has been reputed to apply to some ectotherms including amphibians. However, recent reports provide conflicting support for the pattern, questioning whether Bergmann's clines are generally present in amphibians. In this study, we measured 96,996 adult Plethodon from 3974 populations to test for the presence of Bergmann's clines in these salamanders. Only three Plethodon species exhibited a significant negative correlation between body size and temperature consistent with Bergmann's rule, whereas 37 of 40 species did not display a pattern consistent with this prediction. Further, a phylogenetic comparative analysis found no relationship between body size and temperature among species. A meta-analysis combining our data with the available data for other amphibian species revealed no support for Bergmann's rule at the genus (Plethodon), order (Caudata), or class (Amphibia) levels. Our findings strongly suggest that negative thermal body size clines are not common in amphibians, and we conclude that Bergmann's rule is not generally applicable to these taxa. Thus, evolutionary explanations of Bergmann's clines in other tetrapods need not account for unique life-history attributes of amphibians.
221 citations
TL;DR: The results suggest populations of wood frogs, spotted salamanders, and other amphibian species breeding in temporary pools are likely to benefit from efforts to maintain connectivity between upland forest habitats and aquatic breeding sites.
Abstract: For amphibians that breed in temporary pools, juvenile emigration is an important life-history movement linking the aquatic habitat of larvae to the surrounding upland habitats occupied by maturing animals and adults. However, little is known regarding the habitat preferences and sensitivity to disturbance of newly metamorphosed amphibians. We examined whether selection occurs for closed-canopy forest conditions during emigration by using pitfall traps and drift fences to sample naturally occurring populations of wood frogs (Rand sylvatica) and spotted salamanders (Ambystoma maculatum) along recently created forest-clearcut edges in central Maine. Habitat preferences during emigration were further investigated via an experimental approach that quantified movements of newly metamorphosed wood frogs cultured in artificial pools located along an abrupt forest-power line edge. Among natural populations, the abundance of juveniles and adults of both species declined sharply across a gradient running from relatively mature forest-interior habitat (70-90 yr old) to recently clearcut habitat (2-11 yr old). Similarly, in the power line experiment, juvenile wood frogs showed an emigration preference for closed-canopy habitat immediately upon metamorphosis, with the highest capture rates occurring in microhabitats characterized by dense foliage in both the understory and canopy layers. Our results suggest populations of wood frogs, spotted salamanders, and other amphibian species breeding in temporary pools are likely to benefit from efforts to maintain connectivity between upland forest habitats and aquatic breeding sites. Seminatural field experiments provide a valuable manipulative approach for studying the potential effects of habitat fragmentation on populations of migratory amphibians.
201 citations
TL;DR: Tests of lethal concentrations estimated to kill 50% of a population after 96 h (LC5096‐h) on a wider diversity of species from both eastern and western North America are conducted, substantially increases the available data on amphibian sensitivity to glyphosate formulations that include either POEA surfactant or the equally moderately to highly toxic surfactants of Roundup Original Max.
Abstract: With the increased use of glyphosate-based herbicides (marketed under several names, including Roundup and Vision), there has been a concomitant increased concern about the unintended impacts that particular formulations containing the popular surfactant polyethoxylated tallowamine (POEA) might have on amphibians. Published studies have examined a relatively small number of anuran species (primarily from Australia and eastern North America) and, surprisingly, no species of salamanders. Using a popular formulation of glyphosate (Roundup Original Max), the goal of the present study was to conduct tests of lethal concentrations estimated to kill 50% of a population after 96 h (LC50(96-h)) on a wider diversity of species from both eastern and western North America. Tests were conducted on nine species of stage 25, larval anurans from three families (Ranidae: Rana pipiens, R. clamitans, R. sylvatica, R. catesbeiana, R. cascadae; Bufonidae: Bufo americanus, B. boreas; and Hylidae: Hyla versicolor, Pseudacris crucifer) and four species of larval salamanders from two families (Ambystomatidae: Ambystoma gracile, A. maculatum, A. laterale; and Salamandridae: Notophthalmus viridescens). For the nine species of larval anurans, LC50(96-h) values ranged from 0.8- to 2.0-mg acid equivalents per liter with relatively little pattern in differential sensitivity among the species or families. The four species of larval salamanders were less sensitive than the anurans, with LC50(96-h) values ranging from 2.7- to 3.2-mg acid equivalents per liter and no substantial differences among the species of salamanders. This work substantially increases the available data on amphibian sensitivity to glyphosate formulations that include either POEA surfactants or the equally moderately to highly toxic surfactants of Roundup Original Max and should be useful for improving future risk assessments.
189 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 28 |
| 2024 | 43 |
| 2023 | 45 |
| 2022 | 83 |
| 2021 | 25 |
| 2020 | 16 |