| spontaneous otoacoustic emissions in seven frog species. | spontaneous otoacoustic emissions were screened for in five advanced frog species (hyla cinerea, n = 10 ears; hyla chrysoscelis, n = 10; hyla versicolor, n = 7; leptodactylus albilabris, n = 2; rana pipiens pipiens, n = 8), and two primitive frog species (xenopus laevis, n = 9; bombina orientalis, n = 12). emissions were found in 90% of the advanced species' ears, whereas none of the primitive species' ears had emissions. emission frequencies ranged from 645 hz to 1680 hz. the absence of emissio ... | 1996 | 8951437 |
| distribution and reproductive strategies of gyrinicola batrachiensis (oxyuroidea: pharyngodonidae) in larvae of eight species of amphibians from nebraska. | abstract a total of 462 tadpoles and salamander larvae of 8 species was examined for the presence of gyrinicola batrachiensis from 5 locations in nebraska. infection by g. batrachiensis occurred in tadpoles of rana blairi, r. catesbeiana, r. pipiens, and bufo woodhousii. tadpoles of hyla chrysoscelis, spea bombifrons, and pseudacris maculata and larvae of ambystoma mavortium were not infected with g. batrachiensis. population structure, defined as prevalence, mean abundance, and mean intensity o ... | 2011 | 21506837 |
| finding your mate at a cocktail party: frequency separation promotes auditory stream segregation of concurrent voices in multi-species frog choruses. | vocal communication in crowded social environments is a difficult problem for both humans and nonhuman animals. yet many important social behaviors require listeners to detect, recognize, and discriminate among signals in a complex acoustic milieu comprising the overlapping signals of multiple individuals, often of multiple species. humans exploit a relatively small number of acoustic cues to segregate overlapping voices (as well as other mixtures of concurrent sounds, like polyphonic music). by ... | 2011 | 21698268 |
| water temperature affects susceptibility to ranavirus. | the occurrence of emerging infectious diseases in wildlife populations is increasing, and changes in environmental conditions have been hypothesized as a potential driver. for example, warmer ambient temperatures might favor pathogens by providing more ideal conditions for propagation or by stressing hosts. our objective was to determine if water temperature played a role in the pathogenicity of an emerging pathogen (ranavirus) that infects ectothermic vertebrate species. we exposed larvae of fo ... | 2016 | 27283058 |
| transmission of ranavirus between ectothermic vertebrate hosts. | transmission is an essential process that contributes to the survival of pathogens. ranaviruses are known to infect different classes of lower vertebrates including amphibians, fishes and reptiles. differences in the likelihood of infection among ectothermic vertebrate hosts could explain the successful yearlong persistence of ranaviruses in aquatic environments. the goal of this study was to determine if transmission of a frog virus 3 (fv3)-like ranavirus was possible among three species from d ... | 2014 | 24667325 |
| effects of pesticide exposure and the amphibian chytrid fungus on gray treefrog (hyla chrysoscelis) metamorphosis. | pesticides are detectable in most aquatic habitats and have the potential to alter host-pathogen interactions. the amphibian chytrid fungus, batrachochytrium dendrobatidis (bd), has been associated with amphibian declines around the world. however, bd-associated declines are more prominent in some areas, despite nearly global distribution of bd, suggesting other factors contribute to disease outbreaks. in a laboratory study, the authors examined the effects of 6 different isolates of bd in the p ... | 2014 | 25044296 |
| signal recognition by frogs in the presence of temporally fluctuating chorus-shaped noise. | the background noise generated in large social aggregations of calling individuals is a potent source of auditory masking for animals that communicate acoustically. despite similarities with the so-called "cocktail-party problem" in humans, few studies have explicitly investigated how non-human animals solve the perceptual task of separating biologically relevant acoustic signals from ambient background noise. under certain conditions, humans experience a release from auditory masking when speec ... | 2010 | 21170157 |
| fungal pathogen changes the feeding kinematics of larval anurans. | pathogens can alter host life-history traits by affecting host feeding activities. in anuran tadpoles, keratinized mouthparts (teeth and jaw sheaths) are essential for feeding. batrachochytrium dendrobatidis ( bd ) is a pathogenic fungus of amphibians that can infect these mouthparts and reduce tadpole survival. however, the precise way that bd-induced changes in tadpole mouthparts impact tadpole feeding is unknown. we use high-speed (500 frames/sec) videography to study how bd-induced mouthpart ... | 2010 | 20557202 |
| testing an auditory illusion in frogs: perceptual restoration or sensory bias? | the human auditory system perceptually restores short deleted segments of speech and other sounds (e.g. tones) when the resulting silent gaps are filled by a potential masking noise. when this phenomenon, known as 'auditory induction', occurs, listeners experience the illusion of hearing an ongoing sound continuing through the interrupting noise even though the perceived sound is not physically present. such illusions suggest that a key function of the auditory system is to allow listeners to pe ... | 2010 | 20514342 |
| the acute thermal respiratory response is unique among species in a guild of larval anuran amphibians-implications for energy economy in a warmer future. | climate change is bringing about increased temperatures of amphibian habitats throughout the world, where ectothermic larvae will experience elevated respiratory (metabolic) energy demands. we compared the acute, thermal respiratory response ("trr") of four species of sympatric larval amphibians (lithobates sphenocephalus, l. catesbeianus, scaphiopus holbrookii, and hyla chrysoscelis) to determine species-specific differences in the rate at which metabolic energy requirements increase with tempe ... | 0 | 29128771 |
| expression of the aquaglyceroporin hc-9 in a freeze-tolerant amphibian that accumulates glycerol seasonally. | as ambient temperatures fall in the autumn, freeze-tolerant cope's gray treefrogs, dryophytes chrysoscelis (formerly hyla chrysoscelis), accumulate glycerol as a cryoprotective agent. we hypothesized that these treefrogs express an ortholog of the mammalian aquaglyceroporin aqp9 and that aqp9 expression is upregulated in the cold to facilitate glycerol transport. we sequenced 1790 bp from cloned cdna that codes for a 315 amino acid protein, hc-9, containing the predicted six transmembrane spanni ... | 2017 | 28784850 |
| impacts of batrachochytrium dendrobatidis infection on tadpole foraging performance. | pathogen-induced modifications in host behavior, including alterations in foraging behavior or foraging efficiency, can compromise host fitness by reducing growth and development. chytridiomycosis is an infectious disease of amphibians caused by the fungus batrachochytrium dendrobatidis (bd), and it has played an important role in the worldwide decline of amphibians. in larval anurans, bd infections commonly result in reduced developmental rates, however, the mechanism(s) responsible are unteste ... | 2010 | 20135192 |
| pcr detection of ranavirus in adult anurans from the louisville zoological garden. | ranaviruses are known to cause mortality in a variety of anuran species and have the potential to significantly impact wild and captive frog populations. in this study, 16 captive frogs and toads from the louisville zoological garden were examined for the presence of ranavirus; this group included 14 cope's grey tree frogs (hyla chrysoscelis), an american toad (bufo americanus), and a southern toad (bufo terrestris). all animals were wild caught and were evaluated via polymerase chain reaction ( ... | 2009 | 19746873 |
| finding a mate at a cocktail party: spatial release from masking improves acoustic mate recognition in grey treefrogs. | the 'cocktail party problem' refers to the difficulty that humans have in recognizing speech in noisy social environments. many non-human animals also communicate acoustically in noisy social aggregations, and thus also encounter - and solve - cocktail-party-like problems. relatively few studies, however, have investigated the processes by which non-human animals solve sound source segregation problems in the behaviourally relevant context of acoustic communication. in humans, 'spatial release f ... | 2008 | 19412318 |
| single and interactive effects of malathion, overwintered green frog tadpoles, and cyanobacteria on gray treefrog tadpoles. | amphibian population declines around the world are associated with invasive species, pesticides, pathogens, habitat destruction, or a combination of factors. because contamination is widespread, it represents a relevant environmental stress that can affect the ability of organisms to deal with other factors present in the environment. we examined the effects of the insecticide malathion, larger tadpole competitors (green frogs, rana clamitans), and a toxic cyanobacteria (anabaena spp.) on tadpol ... | 2009 | 18937534 |
| chytridiomycosis impacts predator-prey interactions in larval amphibian communities. | despite ecologists increasingly recognizing pathogens as playing significant roles in community dynamics, few experimental studies have quantified patterns of disease impacts on natural systems. amphibians are experiencing population declines, and a fungal pathogen ( batrachochytrium dendrobatidis; chytridiomycota) is a suspected causal agent in many declines. we studied the effects of a pathogenic fungus on community interactions between the gray treefrog, hyla chrysoscelis, and eastern newts, ... | 2004 | 15235903 |
| antibiotic resistance in coagulase-negative staphylococci isolated from cope's gray treefrogs (hyla chrysoscelis). | organisms belonging to the genus staphylococcus were isolated on mannitol salt agar from the feces of wild caught cope's gray treefrogs (hyla chrysoscelis) from east-central kansas. all 222 presumptive isolates were confirmed as coagulase-negative staphylococci with staphylococcus sciuri and staphylococcus xylosus being most prevalent. antibiotic susceptibility patterns to five different antibiotics were determined and the results indicated 99% of all isolates were resistant to penicillin g and ... | 2001 | 11750814 |
| comparative contractile dynamics of calling and locomotor muscles in three hylid frogs. | isometric twitch and tetanus parameters, force-velocity curves, maximum shortening velocity (vmax) and percentage relaxation between stimuli (%r) across a range of stimulus frequencies were determined for a muscle used during call production (the tensor chordarum) and a locomotor muscle (the sartorius) for three species of hylid frogs, hyla chrysoscelis, h. versicolor and h. cinerea. the call of h. chrysoscelis has a note repetition rate (nrr) approximately twice as fast as the call of h. versic ... | 1995 | 7658189 |
| detection of amplitude-modulated tones by frogs: implications for temporal processing mechanisms. | the whole nerve action potential (ap) from the auditory nerve and midbrain averaged evoked potential (aep) were recorded in hyla chrysoscelis and h. versicolor in response to synthesized amplitude-modulated stimuli with variable modulation frequencies (fm). the ap from these frogs is similar to the potential described for mammals and showed a bandpass characteristic in its ability to follow sinusoidally amplitude-modulated (am) sound stimuli. a lesioning study suggests that the midbrain aep is a ... | 1984 | 6746427 |
| the thermal physiology of two sympatric treefrogs hyla cinerea and hyla chrysoscelis (anura; hylidae). | metabolic rates, temperature acclimation, lipid deposition and temperature tolerance were investigated in two species of hylid treefrogs, the green treefrog (hyla cinerea) and the coastal plain (cope's) gray treefrog (hyla chrysoscelis). the rate of oxygen consumption at rest differed between the two species only at 30 degrees c; there was no difference in respiratory metabolism at lower ambient temperatures. hyla cinerea generally completed metabolic acclimation earlier than h. chrysoscelis, pa ... | 1986 | 2878786 |
| role of sediments in modifying the toxicity of two roundup formulations to six species of larval anurans. | the role of sediment in modifying the toxicity of the original formulation of roundup® and roundup weathermax® was examined in aqueous laboratory tests. six species of anurans (bufo fowleri, hyla chrysoscelis, rana catesbeiana, rana clamitans, rana sphenocephala, and rana pipiens) were exposed at gosner stage 25 to concentrations of the 2 herbicide formulations in 96-h, static, nonrenewal experiments in the presence and absence of sediment. all species tested had lower median lethal concentratio ... | 2014 | 25132544 |
| effects of nitrate on embryos of three amphibian species. | embryos of three aquatic breeding amphibian species, ambystoma mexicanum, hyla chrysoscelis, and rana clamitans, were exposed to increasing levels (0, 5, 10, 30, 60, 100, 300, and 500 mg/l) of nitrate-n (no(3)-) in laboratory, static-renewal experiments. lethal effects were recorded from gosner stage 2 (h. chrysoscelis and r. clamitans) or harrison stage 2 (a. mexicanum) to time of hatching. date of hatching and length at hatching were also compared between treatments for a. mexicanum. no signif ... | 2008 | 18496633 |
| the deal with diel: temperature fluctuations, asymmetrical warming, and ubiquitous metals contaminants. | climate projections over the next century include disproportionately warmer nighttime temperatures ("asymmetrical warming"). cool nighttime temperatures lower metabolic rates of aquatic ectotherms. in contaminated waters, areas with cool nights may provide thermal refugia from high rates of daytime contaminant uptake. we exposed cope's gray tree frogs (hyla chrysoscelis), southern leopard frogs (lithobates sphenocephalus), and spotted salamanders (ambystoma maculatum) to five concentrations of a ... | 2015 | 26142755 |
| ribosomal rna structure in the diploid and phylogenetically polyploid amphibian species hyla and odontophrynus. | ribosomal rna of the diploid amphibian species hyla chrysoscelis and odontophrynus americanus is structurally modified by hidden breaks. phylogenetically polyploid related species like the tetraploid hyla versicolor, the tetraploid odontophrynus americanus and the octoploid ceratophrys ornata do not show hidden breaks in ribosomal rna. structural modifications of rrna molecules in diploid amphibians has no detectable effect on the ribosomal activity in vitro. | 1984 | 6509913 |
| effects of pulsed nitrate exposure on amphibian development. | most toxicity tests investigate constant concentrations of a chemical. concentrations of many compounds in the environment are dynamic, however, and individuals may be more sensitive to pulses of a chemical initiated at specific points during development. realistic toxicity tests are important to accurately assess the toxicity of a compound. bufo americanus and hyla chrysoscelis tadpoles were exposed to concentrations of nitrate, a pervasive stressor in the environment, up to 5 mg/l of no3-n in ... | 2009 | 19199370 |
| novel features of an inducible defense system in larval tree frogs (hyla chrysoscelis). | organisms in aquatic ecosystems must often tolerate variable environmental conditions, including an uncertain risk of predation. individuals that can maintain plastic defenses against predation will increase their survival when predators are present, but will not incur the costs of these defenses when the risk of predation is low and the defense is not induced. larvae of the pond-breeding anuran hyla chrysoscelis develop a conspicuous phenotype in the presence of predators consisting of a bright ... | 2006 | 16602306 |
| an examination of multiple factors affecting community structure in an aquatic amphibian community. | the potential effects of multiple factors structuring certain larval amphibian communities were studied using a pen experiment in a natural pond. potential factors (predation and competition from other species) were allowed to act in a stepwise fashion such that their relative importance could be evaluated. based on a previous study, it was hypothesized that predation by ambystoma salamander larvae on other larval amphibian species would be the most important factor. survival of ambystoma jeffer ... | 1990 | 28313252 |
| relative toxicity of the components of the original formulation of roundup to five north american anurans. | the responses of five north american frog species that were exposed in an aqueous system to the original formulation of roundup were compared. carefully designed and un-confounded laboratory toxicity tests are crucial for accurate assessment of potential risks from the original formulation of roundup to north american amphibians in aquatic environments. the formulated mixture of this herbicide as well as its components, isopropylamine (ipa) salt of glyphosate and the surfactant mon 0818 (contain ... | 2012 | 22137360 |
| predation risk and patch size jointly determine perceived patch quality in ovipositing treefrogs, hyla chrysoscelis. | two of the most important factors determining community structure and diversity within and among habitat patches are patch size and patch quality. despite the importance of patch size in existing paradigms in island biogeography, metapopulation biology, landscape ecology, and metacommunity ecology, and growing conservation concerns with habitat fragmentation, there has been little investigation into how patch size interacts with patch quality. we crossed three levels of patch size (1.13 m2 , 2.5 ... | 0 | 29315522 |
| distribution and reproductive plasticity of gyrinicola batrachiensis (oxyuroidea: pharyngodonidae) in tadpoles of five anuran species. | previous studies on gyrinicola batrachiensis indicate that these pinworms have distinct reproductive strategies dependent on the development time to metamorphosis of their anuran tadpole hosts. in tadpoles of amphibian species with short developmental periods (a few weeks), female nematodes reproduce parthenogenetically, and only produce thick-shelled eggs used as transmission agents from tadpole to tadpole. in contrast, nematodes in tadpoles with longer larval developmental periods (months to y ... | 2017 | 29280071 |
| multivariate phenotypic selection on a complex sexual signal. | animal signals are complex, comprising multiple components that receivers may use to inform their decisions. components may carry information of differing value to receivers, and selection on one component could modulate or reverse selection on another, necessitating a multivariate approach to estimating selection gradients. however, surprisingly few empirical studies have estimated the strength of phenotypic selection on complex signals with appropriate design and adequate power to detect nonli ... | 2017 | 28474734 |
| relative predation risk and risk of desiccation co-determine oviposition preferences in cope's gray treefrog, hyla chrysoscelis. | habitat permanence and threat of predation are primary drivers of community assembly and composition in lentic freshwater systems. pond-breeding amphibians select oviposition sites to maximize fitness and minimize risks of predation and desiccation of their offspring, typically facing a trade-off between the two as predation risk often increases as desiccation risk decreases. to experimentally determine if hyla chrysoscelis partition oviposition along gradients of relative desiccation risk and p ... | 2017 | 28470466 |
| dietary accumulation of inorganic selenium by a larval amphibian (hyla chrysoscelis) and influence on accumulation of background mercury. | larval gray tree frogs (hyla chrysoscelis) were exposed to inorganic se (seo2) added to the diet (10.2 and 86.3 ug/g dw) and monitored for accumulation and effect. background concentrations of hg were also measured in food and carcasses to assess possible effects of se on hg accumulation. selenium was accumulated in a dose dependent manner, and life stages did not differ. no effects of se exposure were observed on survival, growth, or time to metamorphosis. mercury concentrations in carcasses, r ... | 2017 | 28409193 |
| frogs exploit statistical regularities in noisy acoustic scenes to solve cocktail-party-like problems. | noise is a ubiquitous source of errors in all forms of communication [1]. noise-induced errors in speech communication, for example, make it difficult for humans to converse in noisy social settings, a challenge aptly named the "cocktail party problem" [2]. many nonhuman animals also communicate acoustically in noisy social groups and thus face biologically analogous problems [3]. however, we know little about how the perceptual systems of receivers are evolutionarily adapted to avoid the costs ... | 2017 | 28238657 |
| a comparison of helminth faunas of cope's gray ( hyla chrysoscelis ) and green ( hyla cinerea ) treefrogs in areas of recent niche overlap. | this study compares the helminth faunas between cope's gray treefrogs ( hyla chrysoscelis ) and green treefrogs ( hyla cinerea ), in areas where they have recently overlapped due to range expansion by h. cinerea , to determine whether or not 2 species of frogs with a high degree of similarity in many of their life history traits also exhibit similarities in the composition of their helminth assemblages. results of this study did not find significant differences in helminth species diversity when ... | 2017 | 28067112 |
| color perception influences microhabitat selection of refugia and affects monitoring success for a cryptic anuran species. | perceptual-biases are important for understanding an animal's natural history, identifying potential ecological traps, and for developing effective means to monitor individuals and populations. despite research demonstrating anurans having a positive phototactic response towards blue colors, we do not yet understand if color cues are used functionally beyond sexual selection. the aim of our study was to determine if color cues are used in selecting microhabitat, and if anuran's blue-positive pho ... | 2016 | 27235736 |
| inherent directionality determines spatial release from masking at the tympanum in a vertebrate with internally coupled ears. | in contrast to humans and other mammals, many animals have internally coupled ears that function as inherently directional pressure-gradient receivers. two important but unanswered questions are to what extent and how do animals with such ears exploit spatial cues in the perceptual analysis of noisy and complex acoustic scenes? this study of cope's gray treefrog (hyla chrysoscelis) investigated how the inherent directionality of internally coupled ears contributes to spatial release from masking ... | 2016 | 27125545 |
| species-specificity of temporal processing in the auditory midbrain of gray treefrogs: interval-counting neurons. | interval-counting neurons (icns) respond after a threshold number of sound pulses have occurred with specific intervals; a single aberrant interval can reset the counting process. female gray treefrogs, hyla chrysoscelis and h. versicolor, discriminate against synthetic 'calls' possessing a single interpulse interval 2-3 three times the optimal value, suggesting that icns are important for call recognition. the calls of h. versicolor consist of pulses that are longer in duration, rise more slowl ... | 2015 | 25764308 |
| evolutionary adaptations for the temporal processing of natural sounds by the anuran peripheral auditory system. | sensory systems function most efficiently when processing natural stimuli, such as vocalizations, and it is thought that this reflects evolutionary adaptation. among the best-described examples of evolutionary adaptation in the auditory system are the frequent matches between spectral tuning in both the peripheral and central auditory systems of anurans (frogs and toads) and the frequency spectra of conspecific calls. tuning to the temporal properties of conspecific calls is less well establishe ... | 2015 | 25617467 |
| spatial hearing in cope's gray treefrog: ii. frequency-dependent directionality in the amplitude and phase of tympanum vibrations. | anuran ears function as pressure difference receivers, and the amplitude and phase of tympanum vibrations are inherently directional, varying with sound incident angle. we quantified the nature of this directionality for cope's gray treefrog, hyla chrysoscelis. we presented subjects with pure tones, advertisement calls, and frequency-modulated sweeps to examine the influence of frequency, signal level, lung inflation, and sex on ear directionality. interaural differences in the amplitude of tymp ... | 2014 | 24504183 |
| tadpole size, cholinesterase activity, and swim speed in four frog species after exposure to sub-lethal concentrations of chlorpyrifos. | while physiological biomarkers exist to verify exposure of amphibians in natural populations to agricultural chemicals, the ecological relevance of changes in these parameters is often difficult to determine. we compare the relationship between tadpole cholinesterase (che; a common enzymatic biomarker of exposure to op pesticides) and measures of size and swim speed in four native north american species of anurans (hyla chrysoscelis, rana sphenocephala, acris crepitans, and gastrophryne olivacea ... | 2008 | 18448174 |
| a new species of myxidium (myxosporea: myxidiidae), from the western chorus frog, pseudacris triseriata triseriata, and blanchard's cricket frog, acris crepitans blanchardi (hylidae), from eastern nebraska: morphology, phylogeny, and critical comments on amphibian myxidium taxonomy. | during march 2001-april 2004, 164 adult anurans of 6 species (47 rana blairi, 35 rana catesbeiana, 31 hyla chrysoscelis, 31 pseudacris triseriata triseriata, 11 bufo woodhousii, and 9 acris crepitans blanchardi) from pawnee lake, lancaster county, nebraska, were surveyed for myxozoan parasites. of these, 20 of 31 (65%) p. triseriata triseriata and 1 of 9 (11%) a. crepitans blanchardi were infected with a new species of myxidium. myxidium melleni n. sp. (myxosporea) is described from the gallblad ... | 2006 | 16884007 |
| spatial hearing in cope's gray treefrog: i. open and closed loop experiments on sound localization in the presence and absence of noise. | the ability to reliably locate sound sources is critical to anurans, which navigate acoustically complex breeding choruses when choosing mates. yet, the factors influencing sound localization performance in frogs remain largely unexplored. we applied two complementary methodologies, open and closed loop playback trials, to identify influences on localization abilities in cope's gray treefrog, hyla chrysoscelis. we examined localization acuity and phonotaxis behavior of females in response to adv ... | 2014 | 24504182 |
| auditory brainstem responses in cope's gray treefrog (hyla chrysoscelis): effects of frequency, level, sex and size. | our knowledge of the hearing abilities of frogs and toads is largely defined by work with a few well-studied species. one way to further advance comparative work on anuran hearing would be greater use of minimally invasive electrophysiological measures, such as the auditory brainstem response (abr). this study used the abr evoked by tones and clicks to investigate hearing in cope's gray treefrog (hyla chrysoscelis). the objectives were to characterize the effects of sound frequency, sound pressu ... | 2014 | 24442647 |
| differential patterns of accumulation and retention of dietary trace elements associated with coal ash during larval development and metamorphosis of an amphibian. | we performed an experiment in which larval gray tree frogs (hyla chrysoscelis) were raised through metamorphosis on diets increased with a suite of elements associated with coal combustion residues (silver [ag], arsenic [as], cadmium [cd], chromium [cr], copper [cu], mercury [hg], lead [pb], selenium [se], vanadium [v], and zinc [zn]) at "low" and "high" concentrations. we quantified accumulation of metals at three life stages (mid-larval development, initiation of metamorphosis, and completion ... | 2014 | 24169791 |
| climatic variation and the distribution of an amphibian polyploid complex. | the establishment of polyploid populations involves the persistence and growth of the polyploid in the presence of the progenitor species. although there have been a number of animal polyploid species documented, relatively few inquiries have been made into the large-scale mechanisms of polyploid establishment in animal groups. herein we investigate the influence of regional climatic conditions on the distributional patterns of a diploid-tetraploid species pair of gray treefrogs, hyla chrysoscel ... | 2007 | 17922702 |
| pulse-number discrimination by cope's gray treefrog (hyla chrysoscelis) in modulated and unmodulated noise. | in cope's gray treefrog (hyla chrysoscelis), thresholds for recognizing conspecific calls are lower in temporally modulated noise backgrounds compared with unmodulated noise. the effect of modulated noise on discrimination among different conspecific calls is unknown. in quiet, females prefer calls with relatively more pulses. this study tested the hypotheses that noise impairs selectivity for longer calls and that processes akin to dip listening in modulated noise can ameliorate this impairment ... | 2013 | 24116442 |
| spatial release from masking improves sound pattern discrimination along a biologically relevant pulse-rate continuum in gray treefrogs. | many frogs form large choruses during their mating season in which males produce loud advertisement calls to attract females and repel rival males. high background noise levels in these social aggregations can impair vocal perception. in humans, spatial release from masking contributes to our ability to understand speech in noisy social groups. here, we tested the hypothesis that spatial separation between target signals and 'chorus-shaped noise' improves the ability of female gray treefrogs (hy ... | 2013 | 24055623 |
| the response of gray treefrogs to anesthesia by tricaine methanesulfonate (tms or ms-222). | the design of anesthetic protocols for frogs is commonly hindered by lack of information. results from fishes and rodents do not always apply to frogs, and the literature in anurans is concentrated on a few species. we report on the response of treefrogs (hyla chrysoscelis and h. versicolor) to tricaine methanesulfonate. body mass did not differ significantly between the species or between sexes. in the first exposure of a frog to tms, variation in induction time was best explained by species (h ... | 2013 | 24851186 |
| dietary selenomethionine exposure induces physical malformations and decreases growth and survival to metamorphosis in an amphibian (hyla chrysoscelis). | selenium (se) is an essential micronutrient with a narrow therapeutic concentration range. the relative toxicity of se increases as it is biotransformed into organic compounds, primarily selenomethionine (semet), within the aquatic food chain. effects of aquatic se contamination are well quantified for many freshwater fish and aquatic bird species, but impacts on amphibians are not well known. this study investigated the responses of larval cope's gray tree frogs (hyla chrysoscelis) fed a diet e ... | 2013 | 23229196 |
| female preferences for spectral call properties in the western genetic lineage of cope's gray treefrog (hyla chrysoscelis). | female frogs discriminate among potential mates based on individual variation in male advertisement calls. while considerable data have accumulated allowing comparisons of female preference functions among species, we still lack fundamental knowledge about how and why the shapes of preference functions for particular call properties vary among populations within all but a few species. here, we report results from a study aimed at describing female preference functions for spectral call propertie ... | 2012 | 24496093 |
| signal recognition by green treefrogs (hyla cinerea) and cope's gray treefrogs (hyla chrysoscelis) in naturally fluctuating noise. | this study tested three hypotheses about the ability of female frogs to exploit temporal fluctuations in the level of background noise to overcome the problem of recognizing male advertisement calls in noisy breeding choruses. phonotaxis tests with green treefrogs (hyla cinerea) and cope's gray treefrogs (hyla chrysoscelis) were used to measure thresholds for recognizing calls in the presence of noise maskers with (a) no level fluctuations, (b) random fluctuations, or level fluctuations characte ... | 2013 | 23106802 |
| sound level discrimination by gray treefrogs in the presence and absence of chorus-shaped noise. | an important aspect of hearing and acoustic communication is the ability to discriminate differences in sound level. little is known about level discrimination in anuran amphibians (frogs and toads), for which vocal communication in noisy social environments is often critical for reproduction. this study used two-choice phonotaxis tests to investigate the ability of females of cope's gray treefrog (hyla chrysoscelis) to discriminate between two advertisement calls differing only in sound pressur ... | 2012 | 22559390 |
| dip listening and the cocktail party problem in grey treefrogs: signal recognition in temporally fluctuating noise. | dip listening refers to our ability to catch brief "acoustic glimpses" of speech and other sounds when fluctuating background noise levels momentarily decrease. exploiting dips in natural fluctuations of noise contributes to our ability to overcome the "cocktail party problem" of understanding speech in multi-talker social environments. we presently know little about how nonhuman animals solve analogous communication problems. here, we asked whether female grey treefrogs (hyla chrysoscelis) migh ... | 2011 | 22389519 |
| ameliorative effects of sodium chloride on acute copper toxicity among cope's gray tree frog (hyla chrysoscelis) and green frog (rana clamitans) embryos. | urban stormwater runoff is composed of a mixture of components, including polycyclic aromatic hydrocarbons, metals, deicing agents, and many others. the fate of these chemicals is often in stormwater detention ponds that are used by amphibians for breeding. among aquatic organisms, the toxic mechanism for many metals involves interference with active na(+) and cl(-) uptake. addition of cations has been shown to reduce the toxicity of metals among some aquatic organisms through competitive inhibi ... | 2012 | 22278879 |
| spatial release from masking in a free-field source identification task by gray treefrogs. | humans and other animals often communicate acoustically in noisy social groups, in which the background noise generated by other individuals can mask signals of interest. when listening to speech in the presence of speech-like noise, humans experience a release from auditory masking when target and masker are spatially separated. we investigated spatial release from masking (srm) in a free-field call recognition task in cope's gray treefrog (hyla chrysoscelis). in this species, reproduction requ ... | 2012 | 22240459 |
| parallel changes in mate-attracting calls and female preferences in autotriploid tree frogs. | for polyploid species to persist, they must be reproductively isolated from their diploid parental species, which coexist at the same time and place at least initially. in a complex of biparentally reproducing tetraploid and diploid tree frogs in north america, selective phonotaxis--mediated by differences in the pulse-repetition (pulse rate) of their mate-attracting vocalizations--ensures assortative mating. we show that artificially produced autotriploid females of the diploid species (hyla ch ... | 2012 | 22113033 |
| dynamic regulation of aquaglyceroporin expression in erythrocyte cultures from cold- and warm-acclimated cope's gray treefrog, hyla chrysoscelis. | cope's gray treefrog, hyla chrysoscelis,is a freeze-tolerant anuran which accumulates and distributes glycerol as a cryoprotectant before freezing. we hypothesize that hc-3, an aquaglyceroporin member of the mip family of water pores, may play an important role in the process of freeze tolerance by mediating transmembrane passage of glycerol and water during cold-acclimation. the objectives of this study were two-fold: to examine hc-3 protein abundance and cellular localization in erythrocytes f ... | 2011 | 21656914 |
| metal-mediated climate susceptibility in a warming world: larval and latent effects on a model amphibian. | although sophisticated models predict the effects of future temperatures on ectotherms, few also address how ubiquitous sublethal contaminants alter an organism's response to thermal stress. in ectotherms, higher metabolic rates from warming temperatures can beneficially speed metabolism and development. if compounded by chronic, sublethal pollution, additional resource demands for elimination or detoxification may limit their ability to cope with rising temperatures-the toxicant-induced climate ... | 2016 | 26677143 |
| species specificity of temporal processing in the auditory midbrain of gray treefrogs: long-interval neurons. | in recently diverged gray treefrogs (hyla chrysoscelis and h. versicolor), advertisement calls that differ primarily in pulse shape and pulse rate act as an important premating isolation mechanism. temporally selective neurons in the anuran inferior colliculus may contribute to selective behavioral responses to these calls. here we present in vivo extracellular and whole-cell recordings from long-interval-selective neurons (lins) made during presentation of pulses that varied in shape and rate. ... | 2016 | 26614093 |
| abundance, metamorphosis, developmental, and behavioral abnormalities in hyla chrysoscelis tadpoles following exposure to three agrichemicals and methyl mercury in outdoor mesocosms. | | 1998 | 9702370 |
| progesterone and prostaglandin f2α induce species-typical female preferences for male sexual displays in cope's gray treefrog (hyla chrysoscelis). | endocrine systems play critical roles in facilitating sexual behavior in seasonally breeding vertebrates. much of the research exploring this topic has focused on the endocrine correlates of signaling behavior in males and sexual proceptivity in females. what is less understood is how hormones promote the expression of the often complex and highly selective set of stimulus-response behaviors that are observed in naturally breeding animals. in female frogs, phonotaxis is a robust and sensitive bi ... | 2015 | 26454212 |
| an experimental test of noise-dependent voice amplitude regulation in cope's grey treefrog (hyla chrysoscelis). | one strategy for coping with the constraints on acoustic signal reception posed by ambient noise is to signal louder as noise levels increase. termed the 'lombard effect', this reflexive behaviour is widespread among birds and mammals and occurs with a diversity of signal types, leading to the hypothesis that voice amplitude regulation represents a general vertebrate mechanism for coping with environmental noise. support for this evolutionary hypothesis, however, remains limited due to a lack of ... | 2010 | 20823939 |
| sound transmission and the recognition of temporally degraded sexual advertisement signals in cope's gray treefrog (hyla chrysoscelis). | acoustic communication signals degrade as they propagate between signalers and receivers. while we generally understand the degrading effects of sound propagation on the structure of acoustic signals, we know considerably less about how receivers make behavioral decisions based on the perception of degraded signals in sonically and structurally complex habitats where communication occurs. in this study of acoustic mate recognition in cope's gray treefrog, hyla chrysoscelis (cope 1880), we invest ... | 2010 | 20675554 |
| glycerol uptake by erythrocytes from warm- and cold-acclimated cope's gray treefrogs. | cope's gray treefrogs, hyla chrysoscelis, accumulate glycerol during the period of cold acclimation that leads to the development of freeze tolerance. glycerol must cross cell membranes in numerous processes during this time, including exit from hepatocytes where glycerol is synthesized and entry into other tissues, where glycerol is cryoprotective. thus, we hypothesized that erythrocytes from h. chrysoscelis would be permeable to glycerol and that that permeability would be up-regulated during ... | 2010 | 20652259 |
| expression and immunolocalization of aquaporins hc-1, -2, and -3 in cope's gray treefrog, hyla chrysoscelis. | we have previously identified two aquaporins (hc-1, hc-2) and a glyceroporin (hc-3), homologs, respectively, of mammalian aqp1, aqp2, and aqp3, from the freeze-tolerant treefrog hyla chrysoscelis. the objective of the present study was to investigate by western blotting and immunohistofluorescence the expression and localization of these proteins in warm-acclimated, hydrated treefrogs. we hypothesized that patterns of protein expression would reflect unique osmoregulatory roles for the three aqu ... | 2010 | 20416391 |
| does common spatial origin promote the auditory grouping of temporally separated signal elements in grey treefrogs? | 'sequential integration' represents a form of auditory grouping in which temporally separated sounds produced by the same source are perceptually bound together over time into a coherent 'auditory stream'. in humans, sequential integration plays important roles in music and speech perception. in this study of the grey treefrog (hyla chrysoscelis), we took advantage of female selectivity for advertisement calls with conspecific pulse rates to investigate common spatial location as a cue for seque ... | 2008 | 19727419 |
| parallel female preferences for call duration in a diploid ancestor of an allotetraploid treefrog. | the gray treefrog species complex (hyla chrysoscelis and h. versicolor) comprises a single allotetraploid species (h. versicolor) that arose multiple times from hybrid matings between an extant diploid species (h. chrysoscelis) and at least two other extinct diploid treefrogs. while previous studies have investigated female preferences for call duration in the tetraploid, we know little about these preferences in its putative diploid anscestors. here, i report results from two-choice phonotaxis ... | 2008 | 19727325 |
| phonotactic selectivity in two cryptic species of gray treefrogs: effects of differences in pulse rate, carrier frequency and playback level. | the two main spectral components of the advertisement calls of two species of north american gray treefrogs (hyla chrysoscelis and h. versicolor) overlap broadly in frequency, and the frequency of each component matches the sensitivity of one of the two different auditory inner ear organs. the calls of the two species differ in the shape and repetition rate (pulse rate) of sound pulses within trills. standard synthetic calls with one of these spectral peaks and the pulse rate typical of conspeci ... | 2008 | 18689414 |
| preferences based on spectral differences in acoustic signals in four species of treefrogs (anura: hylidae). | frogs have two inner ear organs, each tuned to a different range of frequencies. female treefrogs (hylidae) of three species in which males produce calls with a bimodal spectrum (hyla chrysoscelis, h. versicolor, h. arenicolor) preferred alternatives with a bimodal spectrum to alternatives with a single high-frequency peak. by contrast, females of h. avivoca, in which males produce calls with a single, high-frequency peak, preferred synthetic calls with a single high-frequency peak to calls with ... | 2007 | 17704074 |
| pesticide alters oviposition site selection in gray treefrogs. | understanding the impacts of pesticides on non-target organisms is an important issue for conservation biology. research into the environmental consequences of pesticides has largely focused on pesticide toxicity. we have less understanding of the nonlethal effects of pesticides, and the consequences of nonlethal effects for species and communities. for example, we know very little about whether pesticides alter habitat selection behavior. understanding whether pesticides alter habitat selection ... | 2007 | 17665220 |
| temporal order and the evolution of complex acoustic signals. | the evolution of complex signals may be favoured by hidden preferences or pre-existing sensory biases. females of two species of grey treefrogs (hyla chrysoscelis and hyla versicolor) were tested with combinations of a conspecific advertisement call and acoustic appendages. appendages consisted of aggressive calls and segments of advertisement calls from conspecific males and males of three other species and bursts of filtered noise. when a wide variety of these acoustic appendages followed the ... | 2007 | 17507330 |
| excretion and conservation of glycerol, and expression of aquaporins and glyceroporins, during cold acclimation in cope's gray tree frog hyla chrysoscelis. | cope's gray tree frog hyla chrysoscelis accumulates glycerol during cold acclimation. we hypothesized that, during this process, gray tree frogs adjust renal filtration and/or reabsorption rates to retain accumulated glycerol. during cold acclimation, plasma concentrations of glycerol rose >200-fold, to 51 mmol/l. although fractional water reabsorption decreased, glomerular filtration rate (gfr) and, consequently, urine flow were <5% of warm levels, and fractional glycerol reabsorption increased ... | 2007 | 16973932 |
| advertisement-call preferences in diploid-tetraploid treefrogs (hyla chrysoscelis and hyla versicolor): implications for mate choice and the evolution of communication systems. | signals used for mate choice and receiver preferences are often assumed to coevolve in a lock-step fashion. however, sender-receiver coevolution can also be nonparallel: even if species differences in signals are mainly quantitative, females of some closely related species have qualitatively different preferences and underlying mechanisms. two-alternative playback experiments using synthetic calls that differed in fine-scale temporal properties identified the receiver criteria in females of the ... | 2005 | 15807424 |
| observations on the life history and descriptions of coccidia (apicomplexa) from the western chorus frog, pseudacris triseriata triseriata, from eastern nebraska. | two hundred and twenty-four anurans of 6 species (47 adults and 16 tadpoles of rana blairi, 35 r. catesbeiana, 31 hyla chrysoscelis, 30 adults and 46 tadpoles of pseudacris triseriata triseriata, 11 bufo woodhousii, and 8 acris crepitans) from pawnee lake, lancaster county, nebraska, were surveyed for coccidian parasites during march 2001 to may 2002. of these, 23 of 30 (77%) adults and 4 of 46 (9%) tadpoles of p. t. triseriata shed oocysts of isospora cogginsi n. sp. oocysts of i. cogginsi were ... | 2003 | 12880252 |
| non-parallel coevolution of sender and receiver in the acoustic communication system of treefrogs. | advertisement calls of closely related species often differ in quantitative features such as the repetition rate of signal units. these differences are important in species recognition. current models of signal-receiver coevolution predict two possible patterns in the evolution of the mechanism used by receivers to recognize the call: (i) classical sexual selection models (fisher process, good genes/indirect benefits, direct benefits models) predict that close relatives use qualitatively similar ... | 2002 | 12350274 |
| strongyloidiasis in a cope's grey tree frog (hyla chrysoscelis). | a male cope's grey tree frog (hyla chrysoscelis) died spontaneously with ventral subcutaneous edema and was necropsied. thickening of the intestinal mucosa was observed histopathologically, with villous atrophy and intraepithelial nematodes present. adult female strongyloides sp. nematodes were isolated from the fixed intestinal tract, the first time this nematode genus has been recovered from this frog genus. intestinal strongyloidiasis should be considered as a cause for protein-losing enterop ... | 2001 | 12790404 |
| comparison of long-term perifused pars intermedia of anolis carolinensis, rana pipiens and hyla chrysoscelis: their responses to dopamine. | pituitary pars nervosa-pars intermedia of anolis carolinensis, rana pipiens and hyla crysoscelis were perifused with synthetic medium 199 for up to 35 h. the pre- and post-perifused tissues were examined by electron microscopy. no neuronal endings were found in anolis tissue, but both rana and hyla had occasional synaptic end bulbs, which remained visible in the post-perifused tissue, although the synaptic vesicles appeared to cluster in the center of the end bulbs. exposure to dopamine hcl from ... | 2004 | 15687732 |
| threat of predation negates density effects in larval gray treefrogs. | while density-dependence is central to most theory regarding population regulation and community structure, specific mechanisms that modify its effects in the absence of changes in consumer-resources ratios (e.g., thinning) are not well understood. to determine if the threat of predation alters effects of density, we investigated the interaction between density of larval treefrogs (hyla chrysoscelis) and the non-lethal presence of a predatory fish (enneacanthus obesus). a significant density by ... | 2004 | 14722747 |
| season and testosterone affect contractile properties of fast calling muscles in the gray tree frog hyla chrysoscelis. | in anurans, circulating levels of androgens influence certain secondary sexual characteristics that are expressed only during the breeding season. we studied the contractile properties of external oblique muscles (used to power sound production) in a species of north american gray tree frog, hyla chrysoscelis, during the breeding season and also in testosterone-treated captive males and females after the breeding season. compared with the muscles of breeding-season males, the trunk muscles of po ... | 2003 | 12595277 |
| developmental effects of ambient uv-b light and landfill leachate in rana blairi and hyla chrysoscelis. | this study assessed the effects of ambient uv light on the development of two native species of anurans, rana blairi and hyla chrysoscelis, during their normal breeding season in oklahoma. additionally, the effects of ambient uv light and water contaminated with landfill leachate in rana blairi were examined. embryos were collected from the field and distributed equally among replicates of four filter treatments of ambient uv light in experimental tubs filled with either fetax solution or landfi ... | 2002 | 12481861 |
| development of the urostyle during metamorphosis in five species of anurans. | normal development of the urostyle is described during late stages of metamorphosis in five species of anurans: xenopus laevis (daudin), bufo americanus holbrook, pseudacris triseriata (wied), hyla chrysoscelis cope, and rana pipiens schreber. the developing urostyle of all five species is composed of essentially the same cartilaginous elements: one pair of basidorsals above the notochord and the subtended hypochord. among the five species there is variation in such details as the number of spin ... | 1979 | 30200677 |
| cloning of the 18s rdna gene, an internal transcribed spacer, and the 5' region of the 28s rdna gene of cope's gray treefrog, hyla chrysoscelis. | the location of rdna genes on the chromosomes of most species is identical within that species, usually occurring on the same chromosome or chromosomes. this is not the case in cope's gray treefrog, hyla chrysoscelis, where the rdna genes are polymorphic for chromosome location. the occasions leading to this polymorphism have yet to be determined. the first step in understanding the nature of the polymorphism is the characterization of the ribosomal gene array. here we describe the cloning, sequ ... | 2001 | 11306807 |
| replication banding patterns of the diploid-tetraploid treefrogs hyla chrysoscelis and h. versicolor. | populations of the diploid-tetraploid treefrogs hyla chrysoscelis and h. versicolor can be defined by the polymorphic positions of the nucleolar organizing regions (nors) on their chromosomes. evidence from nor positions and interstitial telomere sequence data shows that gene flow between h. chrysoscelis populations appears to be restricted, with contact occurring only in narrow "hybrid" zones. hyla versicolor appears to have had multiple origins from h. chrysoscelis populations, and this, too, ... | 2000 | 10773656 |
| power output of sound-producing muscles in the tree frogs hyla versicolor and hyla chrysoscelis. | sound-producing muscles provide the opportunity of studying the limits of power production at high contractile frequencies. we used the work loop technique to determine the power available from the external oblique muscles in two related species of north american gray tree frog, hyla chrysoscelis and hyla versicolor. these trunk muscles contract cyclically, powering high-intensity sound production in anuran amphibians. the external oblique muscles in h. chrysoscelis have an in vivo operating fre ... | 1999 | 10539971 |
| contractile properties of muscles used in sound production and locomotion in two species of gray tree frog. | the sound-producing muscles of frogs and toads are interesting because they have been selected to produce high-power outputs at high frequencies. the two north american species of gray tree frog, hyla chrysoscelis and hyla versicolor, are a diploid-tetraploid species pair. they are morphologically identical, but differ in the structure of their advertisement calls. h. chrysoscelis produces very loud pulsed calls by contracting its calling muscles at approximately 40 hz at 20 degrees c, whereas, ... | 1999 | 10539970 |
| endo-porter-mediated delivery of phosphorodiamidate morpholino oligos (pmos) in erythrocyte suspension cultures from cope's gray treefrog hyla chrysoscelis. | cope's gray treefrog, hyla chrysoscelis, is a freeze-tolerant anuran that accumulates cryoprotective glycerol during cold acclimation. h. chrysoscelis erythrocytes express the aquaglyceroporin hc-3, which facilitates transmembrane glycerol and water movement. aquaglyceroporins have no pharmacological inhibitors, and no genetic knockout tools currently exist for h. chrysoscelis. a phosphorodiamidate morpholino oligo (pmo)-mediated expression knockdown approach was therefore pursued to provide a m ... | 2011 | 21548895 |
| spectral preferences and the role of spatial coherence in simultaneous integration in gray treefrogs (hyla chrysoscelis). | the perceptual analysis of acoustic scenes may often require the integration of simultaneous sounds arising from a single source. few studies have investigated the cues that promote simultaneous integration in the context of acoustic communication in nonhuman animals. this study of cope's gray treefrog (hyla chrysoscelis) examined female preferences based on spectral features of conspecific male advertisement calls to test the hypothesis that cues related to common spatial origin promote the per ... | 2010 | 20853948 |
| isolation and characterization of simple sequence repeat loci in the gray tree frog, hyla chrysoscelis. | a gray tree frog (hyla chrysoscelis) genomic library was constructed and characterized with regard to the incidence and complexity of simple sequence repeat (ssr) loci. the partial genomic library, containing approximately 10,000 clones with an average-sized insert of 350 bp, was screened with six ssr repeat oligonucleotides (ac, ag, acg, agc, aac, and aag). screening identified 31 unique positive clones containing 41 ssr loci. sequences of tandemly arrayed dinucleotide repeats were more common ... | 1999 | 10464791 |
| food deprivation during different periods of tadpole (hyla chrysoscelis) ontogeny affects metamorphic performance differently. | tadpoles in small, ephemeral pools whose duration and food content are unpredictable can potentially encounter substantial variation in diet composition and availability. we compared the effects of 10 days of food deprivation occurring early, midway and late in ontogeny on the metamorphic size and bioenergetic properties of hyla chrysoscelis tadpoles. tadpoles fed throughout ontogeny were controls. metamorphs from tadpoles starved early and midway in ontogeny had the same snout-vent length and d ... | 1995 | 28307001 |
| speciation by polyploidy in treefrogs: multiple origins of the tetraploid, hyla versicolor. | speciation by polyploidy is rare in animals, yet, in vertebrates, there is a disproportionate concentration of polyploid species in anuran amphibians. sequences from the cytochrome b gene of the mitochondrial dna (mtdna) were used to determine phylogenetic relationships among 37 populations of the diploid-tetraploid species pair of gray treefrogs, hyla chrysoscelis and hyla versicolor. the diploid species, h. chrysoscelis, consists of an eastern and a western lineage that have 2.3% sequence dive ... | 1994 | 28568266 |
| fish predation in size-structured populations of treefrog tadpoles. | the effects of tadpole body size, tadpole sibship, and fish body size on predation of gray treefrog tadpoles, hyla chrysoscelis, were studied in laboratory and artificial pond experiments. tadpole body size had a significantly positive effect on the survival of tadpoles in all experiments. the relationship between tadpole biomass eaten and biomass available suggested that fish were not satiated when consuming the largest tadpoles. large tadpoles were probably better able to evade predators. a di ... | 1988 | 28312677 |
| restriction endonuclease mapping of ribosomal rna genes: sequence divergence and the origin of the tetraploid treefrog hyla versicolor. | hyla chrysoscelis (2n = 24) and h. versicolor (2n = 48) are a diploid-tetraploid species pair of treefrogs. restriction endonuclease mapping of ribosomal rna (rrna) gene repeat units of diploids collected from eastern and western populations reveals no differences within rrna gene coding regions but distinctive differences within the nontranscribed spacers. a minimum of two physical maps is required to construct an rrna gene map for the tetraploid, whose repeat units appear to be a composite, wi ... | 1986 | 3017294 |
| effects of parentage on competitive ability and vulnerability to predation in hyla chrysoscelis tadpoles. | four sibships of hyla chrysoscelis larvae were used to examine the effects of parentage on mass at day 23 of growth and on vulnerability to predation. the h. chrysoscelis larvae were raised alone, in competition with rana clamitans larvae, and in competition with siblings. vulnerability to predation by adult notophthalmus viridescens dorsalis was evaluated for hyla that had been raised in competition with siblings. sibships differed in body mass and vulnerability to predation. competition with r ... | 1986 | 28310127 |
| species specificity and temperature dependency of temporal processing by the auditory midbrain of two species of treefrogs. | the mating (advertisement) calls of two sibling species of gray treefrogs, hyla versicolor and hyla chrysoscelis, are spectrally identical but differ in trill rate; being higher for h. chrysoscelis. single-unit recordings were made from the torus semicircularis of both species to investigate the neural mechanisms by which this species-specific temporal feature is analyzed. using sinusoidally amplitude-modulated (am) white noise as a stimulus, the temporal selectivity of these midbrain auditory n ... | 1985 | 3837112 |
| diploid and tetraploid grey treefrogs (hyla chrysoscelis and hyla versicolor) have similar metabolic rates. | we measured oxygen consumption of the diploid frog hyla chrysoscelis and its recently evolved tetraploid cryptic species hyla versicolor at rest and during forced locomotory exercise. we also measured whole-body lactic acid concentrations of individuals of the two species at rest and following 4 min of exercise. contrary to predictions based on tissue-culture experiments, rates of organismal metabolism are not different in this diploid/tetraploid species pair: the diploid and tetraploid species ... | 1985 | 2864204 |
| ribosomal rna gene number and sequence divergence in the diploid-tetraploid species pair of north american hylid tree frogs. | hyla chrysoscelis (2n = 24) and h. versicolor (2n = 48) are a diploid-tetraploid species pair of tree frogs. hybridization saturation of isolated 125i-labeled ribosomal rnas (rrnas) with filter-immobilized dna shows that there are twice as many rrna genes in the tetraploid as in the diploid. for the diploid, saturation occurs at 0.037%, from which it is calculated that there are about 618 copies of the (18 s + 28 s) rrna genes per haploid genome. analysis of the extent of hybridization and also ... | 1983 | 6860296 |
| further evidence for a polymorphism in gametic segregation in the tetraploid treefrog hyla versicolor using a glutamate oxaloacetic transaminase locus. | intra- and interspecific cross combinations between the tetraploid treefrog hyla versicolor, and between h. versicolor and the diploid treefrog hyla chrysoscelis were performed. progeny phenotypes resulting from these crosses were examined electrophoretically using a polymorphic glutamate oxaloacetic transaminase (got-1) locus, to determine the mechanism of chromosome segregation in h. versicolor, and to test theoretical expectations for isozyme expression in interspecific (2n x 4n or 4n x 2n) h ... | 1983 | 6852524 |
| gene dosage effects on mdh isozyme expression in diploid, triploid, and tetraploid treefrogs of the genus hyla. | electrophoretic staining intensities at a polymorphic malate dehydrogenase locus (mdh-1) in the tetraploid treefrog hyla versicolor and diploid hyla chrysoscelis were compared using intraspecific and interspecific crosses. gene dosage levels within the three ploidies were additive for the expression of isozymes encoded by this locus. using densitometry, phenotypes from intraspecific tetraploid progeny conformed to a tetraploid gene dosage model, while phenotypes from interspecific hybrids confor ... | 2006 | 7108184 |
| competition for two resources. | tadpoles of the tree frog, hyla chrysoscelis, were raised at low and high levels of two independent, growth-limiting resources: solid food substrates and ingestible particles. the effect of resource level on intraspecific competition was measured as the relative importance of interference versus exploitative competitive mechanisms. the levels of both solid food substrates and particles affected the outcome of competition among the tadpoles, despite their independent effects on growth. current mo ... | 1981 | 28310007 |