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Ecology and Evolutionary Biology Commons™
Open Access. Powered by Scholars. Published by Universities.®
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- Amphibian (2)
- Amphibians (2)
- Anura (2)
- Cell biology (2)
- Myogenesis (2)
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- 16S (1)
- Africa (1)
- Afromontane (1)
- Amphibia (1)
- Amphibian phulogeny (1)
- Amphibian tree of life (1)
- Anura; Frogs; Phylogeny; Systematics; Ribosomal DNA (1)
- Anurans (1)
- Atelophryniscus chrysophorus tadpoles (1)
- Atelopus tricolor tadpoles (1)
- Bale Mountains National Park (1)
- Cell development (1)
- Central America (1)
- Chondrocrania; anatomy; larvae; Leptodactylus; variation; phylogeny (1)
- Chondrocranium (1)
- Chytrid (1)
- Cryptic speciation (1)
- DNA sequence (1)
- Decline (1)
- Developmental biology (1)
- Ecology (1)
- Ethiopia (1)
- Evolution (1)
- Experiment (1)
- Frog (1)
Articles 1 - 14 of 14
Full-Text Articles in Ecology and Evolutionary Biology
Long-Term Data For Endemic Frog Genera Reveal Potential Conservation Crisis In The Bale Mountains, Ethiopia, David J. Gower, Roman K. Aberra, Silvia Schwaller, Malcolm J. Largen, Ben Collen, Stephen Spawls, Michele Menegon, Breda M. Zimkus, Rafael O. De Sá, Et Al.
Long-Term Data For Endemic Frog Genera Reveal Potential Conservation Crisis In The Bale Mountains, Ethiopia, David J. Gower, Roman K. Aberra, Silvia Schwaller, Malcolm J. Largen, Ben Collen, Stephen Spawls, Michele Menegon, Breda M. Zimkus, Rafael O. De Sá, Et Al.
Biology Faculty Publications
Populations of many frogs have declined alarmingly in recent years, placing nearly one third of the > 6,000 species under threat of extinction. Declines have been attributed largely to habitat loss, environmental degradation and/or infectious diseases such as chytridiomycosis. Many frogs undergo dramatic natural population fluctuations such that long-term data are required to determine population trends without undue influence of stochastic factors. We present long-term quantitative data (individuals encountered per person hour of searching) for four monotypic frog genera endemic to an Afromontane region of exceptional importance but growing conservation concern: one endemic to the Ethiopian highlands (Spinophrynoides osgoodi) and three …
Rapid Range Expansion In The Great Plains Narrow-Mouthed Toad (Gastrophryne Olivacea) And A Revised Taxonomy For North American Microhylids, Jeffrey W. Streicher, Christian L. Cox, Jonathan A. Campbell, Eric N. Smith, Rafael O. De Sá
Rapid Range Expansion In The Great Plains Narrow-Mouthed Toad (Gastrophryne Olivacea) And A Revised Taxonomy For North American Microhylids, Jeffrey W. Streicher, Christian L. Cox, Jonathan A. Campbell, Eric N. Smith, Rafael O. De Sá
Biology Faculty Publications
We investigated genetic variation within the Great Plains narrow-mouthed toad, Gastrophryne olivacea, across its geographic range in the United States and Mexico. An analysis of mitochondrial DNA (mtDNA) from 105 frogs revealed remarkably low levels of genetic diversity in individuals inhabiting the central United States and northern Mexico. We found that this widespread matrilineal lineage is divergent (ca. 2% in mtDNA) from haplotypes that originate from the western United States and western coast of Mexico. Using a dataset that included all five species of Gastrophryne and both species of the closely related genus Hypopachus, we investigated the phylogenetic …
Molecular Systematics Of The Middle American Genus Hypopachus (Anura: Microhylidae), Eli Greenbaum, Eric N. Smith, Rafael O. De Sá
Molecular Systematics Of The Middle American Genus Hypopachus (Anura: Microhylidae), Eli Greenbaum, Eric N. Smith, Rafael O. De Sá
Biology Faculty Publications
We present the first phylogenetic study on the widespread Middle American microhylid frog genus Hypopachus. Partial sequences of mitochondrial (12S and 16S ribosomal RNA) and nuclear (rhodopsin) genes (1275 bp total) were analyzed from 43 samples of Hypopachus, three currently recognized species of Gastrophryne, and seven arthroleptid, brevicipitid and microhylid outgroup taxa. Maximum parsimony (PAUP), maximum likelihood (RAxML) and Bayesian inference (MrBayes) optimality criteria were used for phylogenetic analyses, and BEAST was used to estimate divergence dates of major clades. Population-level analyses were conducted with the programs NETWORK and Arlequin. Results confirm the placement of Hypopachus …
Is The Amphibian Tree Of Life Really Fatally Flawed?, Darrel R. Frost, Taran Grant, Julian Faivovich, Raoul H. Bain, Alexander Haas, Celio F.B. Haddad, Rafael O. De Sá, Et Al.
Is The Amphibian Tree Of Life Really Fatally Flawed?, Darrel R. Frost, Taran Grant, Julian Faivovich, Raoul H. Bain, Alexander Haas, Celio F.B. Haddad, Rafael O. De Sá, Et Al.
Biology Faculty Publications
Wiens (2007, Q. Rev. Biol. 82, 55–56) recently published a severe critique of Frost et al.'s (2006, Bull. Am. Mus. Nat. Hist. 297, 1–370) monographic study of amphibian systematics, concluding that it is “a disaster” and recommending that readers “simply ignore this study”. Beyond the hyperbole, Wiens raised four general objections that he regarded as “fatal flaws”: (1) the sampling design was insufficient for the generic changes made and taxonomic changes were made without including all type species; (2) the nuclear gene most commonly used in amphibian phylogenetics, RAG-1, was not included, nor were the morphological characters that had justified …
Phylogenetic Analyses Of Mtdna Sequences Reveal Three Cryptic Lineages In The Widespread Neotropical Frog Leptodactylus Fuscus (Schneider, 1799) (Anura, Leptodactylidae), Arley Camargo, Rafael O. De Sá, W. Ronald Heyer
Phylogenetic Analyses Of Mtdna Sequences Reveal Three Cryptic Lineages In The Widespread Neotropical Frog Leptodactylus Fuscus (Schneider, 1799) (Anura, Leptodactylidae), Arley Camargo, Rafael O. De Sá, W. Ronald Heyer
Biology Faculty Publications
Leptodactylus fuscus is a neotropical frog ranging from Panamá to Argentina, to the east of the Andes mountains, and also inhabiting Margarita, Trinidad, and the Tobago islands. We performed phylogenetic analyses of 12S rRNA, 16S rRNA, tRNA-Leu, and ND1 mitochondrial (mt) DNA sequences from specimens collected across the geographic distribution of L. fuscus to examine two alternative hypotheses: (i) L. fuscus is a single, widely distributed species, or (ii) L. fuscus is a species complex. We tested statistically for geographic association and partitioning of genetic variation among mtDNA clades. The mtDNA data supported the hypothesis of several cryptic species within …
On The Enigmatic Distribution Of The Honduran Endemic Leptodactylus Silvanimbus (Amphibia: Anura: Lep Todactylidae), W. Ronald Heyer, Rafael O. De Sá, Sarah Muller
On The Enigmatic Distribution Of The Honduran Endemic Leptodactylus Silvanimbus (Amphibia: Anura: Lep Todactylidae), W. Ronald Heyer, Rafael O. De Sá, Sarah Muller
Biology Faculty Publications
Most species of the frog genus Leptodactylus occur in South America, and all authors who have treated the zoogeography of the genus have concluded that it originated somewhere in South America (e.g., Savage 1982). Savage (1982,518) summarized the historical herpetofaunal units of the Neotropics as follows: "All evidence points to an ancient contiguity and essential similarity of a generalized tropical herpetofauna that ranged over tropical North, Middle, and most of South America in Cretaceous-Paleocene times. Descendents of this fauna are represented today by the South and Middle American tracks (Elements). To the north of this fauna ranged a subtropical-temperate Laurasian …
The Tadpole Of Proceratophrys Avelinoi (Anura: Leptodactylidae), Rafael O. De Sá, José A. Langone
The Tadpole Of Proceratophrys Avelinoi (Anura: Leptodactylidae), Rafael O. De Sá, José A. Langone
Biology Faculty Publications
The genus Proceratoprhrys is poorly known. It consists of 14 currently recognized species (Frost, 2000) of medium-sized frogs distributed from northeastern Argentina and Paraguay to southeast Amazonia (Rondonia State), eastern and southern Brazil. Proceratophrys avelinoi was described from Misiones, Argentina (Mercadal de Barrio and Barrio, 1993). The larval stage of this species is unknown. Herein, we describe the tadpole and the characteristics of the internal oral anatomy of P avelinoi using scanning electron micros- copy (SEM).
Chondrocranium And Visceral Skeleton Of Atelopus Tricolor And Atelophryniscus Chrysophorus, E O. Lavilla, Rafael O. De Sá
Chondrocranium And Visceral Skeleton Of Atelopus Tricolor And Atelophryniscus Chrysophorus, E O. Lavilla, Rafael O. De Sá
Biology Faculty Publications
Atelopus tricolor and Atelophryniscus chrysophorus have gastromyzophorous tadpoles. Aside from specific differences, the larval chondrocrania and visceral skeletons show several shared character states, including an almost quadrangular, open chondrocranium , cornua trabeculae with expanded tips, cartilago suprarostralis as a single element, a posteriorly projected arcus subocularis quadrati, a closed muscular tunnel, and a simplified branchial basket, with only three pairs of ceratobranchiales. They are compared with diverse character states of suctorial larvae considering them as causally related to the stream life adaptations.
Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice
Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice
Biology Faculty Publications
The timing and pattern of myogenesis varies among anurans that have been studied and the different pat- terns may provide useful phylogenetic information. Specific myogenic markers have been described (Muntz, 1975; Kielbowna, 1981; Boudjelida & Muntz, 1987; Radice et al., 1989) and they can provide infor- mation on evolutionary changes for closely related lineages within a clade. For example, we previously com- pared first appearance of a muscle-specific protein, first twitch of axial muscle, onset of multinucleation within axial myotome, and first heartbeat in two pipid genera (Smetanick et al., 1999). We found that although the timing of myogenesis differed, …
The Timing And Pattern Of Myogenesis In Hymenochirus Boettgeri, Matthew T. Smetanick, Rafael O. De Sá
The Timing And Pattern Of Myogenesis In Hymenochirus Boettgeri, Matthew T. Smetanick, Rafael O. De Sá
Biology Faculty Publications
Differences in the relative timing of homologous developmental events among closely related species, known as heterochronies, may provide valuable clues in understanding evolutionary relationships (McKinney, 1988; McNamara, 1995). Examining the timing of myogenic events is a relatively easy and effective method for finding heterochronic events. For example, whether muscle proteins and myofibrils appear before or after multinucleation can be determined through histological techniques (Kielbowna, 1981). Simple observations of live specimens can pinpoint functional landmarks such as first twitch (spontaneous or due to external stimuli) and first heartbeat.
Development Of The Suprarostral Plate Of Pipoid Frogs, Rafael O. De Sá, Charles C. Swart
Development Of The Suprarostral Plate Of Pipoid Frogs, Rafael O. De Sá, Charles C. Swart
Biology Faculty Publications
The rostral region of nonpipoid tadpoles has two sets of cartilages, the cornua trabeculae and the suprarostral cartilages, whereas the rostral region in pipoid larvae is occupied by a single and continuous cartilage, the suprarostral plate. The homology of this region in pipoid and nonpipoids tadpoles has been controversial. We examined the early formation and development of the suprarostral plate using serially cross-sectioned specimens of Rhinophrynus, Xenopus, and Hymenochirus. We conclude that the cartilaginous structures present in the rostral area of pipoid and nonpipoid larvae are homologous. Furthermore, we found two different developmental patterns among pipoid larvae. The chondrocranium …
The Biology Of Xenopus By R. C. Tinsley And H. C. Kobel, Rafael O. De Sá
The Biology Of Xenopus By R. C. Tinsley And H. C. Kobel, Rafael O. De Sá
Biology Faculty Publications
The Biology of Xenopus presents a summary of current knowledge about a single genus resulting from a symposium held at the Zoological Society of London in September 1992. This approach to summarizing available information has also been taken for other taxa, such as Atelopus (Lotters, 1996). However, the task of compiling data for Xenopus is enormous relative to any other amphibian group, because Xenopus laevis has become a model system for molecular and development research (Cannatella and de Sa, 1993). Unfortunately, most of our knowledge of Xenopus is biased toward this single species. There are about 20 recognized species of …
Chondrocranial Morphology Of Leptodactylus Larvae (Leptodactylidae: Leptodactylinae): Its Utility In Phylogenetic Reconstruction, Peter M. Larson, Rafael O. De Sá
Chondrocranial Morphology Of Leptodactylus Larvae (Leptodactylidae: Leptodactylinae): Its Utility In Phylogenetic Reconstruction, Peter M. Larson, Rafael O. De Sá
Biology Faculty Publications
Chondrocranial morphology of leptodactylid frogs is scarcely known and has not been completely described for any species of Leptodactylus. We describe the diversity of chondrocranial morphology in the genus Leptodactylus based on the analysis of 22 species, representing the four species groups: the fuscus Group, ocellatus Group, melanonotus Group, and pentadactylus Group. Furthermore, 26 characters are identified and used in a phylogenetic analysis. The phylogenetic analysis using Physalaemus, Crossodactylus, and Hylodes as outgroups suggests two monophyletic clades within Leptodactylus: the melanonotus-ocellatus clade and the pentadactylusfuscus clade. However, it does not support the monophyly of the species groups as currently recognized …
Ribosomal Dna And The Phylogeny Of Frogs, David M. Hills, Loren K. Ammerman, Michael T. Dixon, Rafael O. De Sá
Ribosomal Dna And The Phylogeny Of Frogs, David M. Hills, Loren K. Ammerman, Michael T. Dixon, Rafael O. De Sá
Biology Faculty Publications
Phylogenetic analysis of 1656 aligned sites in the 28S ribosomal RNA gene of frogs supports some of the recently recognized higher groups of anurans but provides counter-support for others. The 28S rDNA data support the monophyly of the recently recognized Pipanura (me- sobatrachians plus neobatrachians), which in turn indicates paraphyly of archaeobatrachians. Me- sobatrachians (pelobatoids plus pipoids), which are either considered paraphyletic or weakly sup- ported as monophyletic in morphological analyses, also receive support as a monophyletic group from the 28S rDNA data. Hyloidea (=Bufonoidea), which is widely recognized but lacks morphological support, receives some molecular support as being monophyletic. …