Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
PLoS One ; 19(3): e0298970, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38457426

RESUMEN

DNA barcoding, based on mitochondrial markers, is widely applied in species identification and biodiversity studies. The aim of this study was to establish a barcoding reference database of fishes inhabiting the Cube River from Western Ecuador in the Chocó-Darien Global Ecoregion (CGE), a threatened ecoregion with high diversity and endemism, and evaluate the applicability of using barcoding for the identification of fish species. Barcode sequences were obtained from seven orders, 17 families, 23 genera and 26 species, which were validated through phylogenetic analysis, morphological measurements, and literature review. Our results showed that 43% of fish species in this region are endemic, confirmed the presence of known species in the area, and included the addition of three new records of native (Hoplias microlepis, Rhamdia guatemalensis and Sicydium salvini) and an introduced species (Xiphophorus maculatus) to Ecuador. In addition, eight species were barcoded for the first time. Species identification based on barcoding and morphology showed discrepancy with species lists from previous studies in the CGE, suggesting that the current baseline of western fishes of Ecuador is still incomplete. Because this study analyzed fishes from a relatively small basin (165 km2), more molecular-based studies focusing on fish are needed to achieve a robust sequence reference library of species inhabiting Western Ecuador. The new sequences of this study will be useful for future comparisons and biodiversity monitoring, supporting the application of barcoding tools for studying fish diversity in genetically unexplored regions and to develop well-informed conservation programs.


Asunto(s)
Bagres , Ríos , Humanos , Animales , Especies Introducidas , Código de Barras del ADN Taxonómico/métodos , Filogenia , Ecuador , Complejo IV de Transporte de Electrones/genética , Peces , ADN/genética , Bagres/genética , Biodiversidad
2.
Proc Biol Sci ; 291(2016): 20240054, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38351799

RESUMEN

In males, large testes size signifies high sperm production and is commonly linked to heightened sperm competition levels. It may also evolve as a response to an elevated risk of sperm depletion due to multiple mating or large clutch sizes. Conversely, weapons, mate or clutch guarding may allow individuals to monopolize mating events and preclude sperm competition, thereby reducing the selection of large testes. Herein, we examined how paternal care, sexual size dimorphism (SSD), weaponry and female fecundity are linked to testes size in glassfrogs. We found that paternal care was associated with a reduction in relative testes size, suggesting an evolutionary trade-off between testes size and parenting. Although females were slightly larger than males and species with paternal care tended to have larger clutches, there was no significant relationship between SSD, clutch size and relative testes size. These findings suggest that the evolution of testes size in glassfrogs is influenced by sperm competition risk, rather than sperm depletion risk. We infer that clutch guarding precludes the risk of fertilization by other males and consequently diminishes selective pressure for larger testes. Our study highlights the prominent role of paternal care in the evolution of testes size in species with external fertilization.


Asunto(s)
Responsabilidad Parental , Testículo , Humanos , Masculino , Femenino , Animales , Semen , Espermatozoides/fisiología , Reproducción , Conducta Sexual Animal/fisiología
4.
PeerJ ; 11: e14715, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36879909

RESUMEN

Background: Pristimantis is the most diverse genus of terrestrial frogs. Historically, it has been divided into several phenetic groups in order to facilitate species identification. However, in light of phylogenetic analysis, many of these groups have been shown to be non-monophyletic, denoting a high degree of morphological convergence and limited number of diagnostic traits. In this study, we focus on the Pristimantis myersi group, an assemblage of small rainfrogs distributed throughout the Andes of Ecuador and Colombia, whose external morphology is highly conserved, and its species diversity and evolutionary relationships largely unknown. Methods: We inferred a new phylogenetic hypothesis for the frog genus Pristimantis, including all available sequences of the mtDNA 16S rRNA, as well as new DNA sequences from 175 specimens. Our sampling included 19 of the 24 species currently recognized as part of the Pristimantis myersi group. Results: Our new evolutionary hypothesis recovered the P. myersi group as non-monophyletic and composed of 16 species. Therefore, we exclude P. albujai, P. bicantus, P. sambalan, and P. nelsongalloi in order to preserve the monophyly of the group. We discovered at least eight candidate species, most of them hidden under the names of P. leoni, P. hectus, P. festae, P. gladiator, and P. ocreatus. Discussion: Our results reveal the occurrence of a high level of cryptic diversity to the species level within the P. myersi group and highlight the need to redefine some of its species and reassess their conservation status. We suggest that the conservation status of six species within the group need to be re-evaluated because they exhibit smaller distributions than previously thought; these species are: P. festae, P. gladiator, P. hectus, P. leoni, P. ocreatus, and P. pyrrhomerus. Finally, given that the Pristimantis myersi group, as defined in this work, is monophyletic and morphologically diagnosable, and that Trachyphrynus is an available name for the clade containing P. myersi, we implement Trachyphrynus as a formal subgenus name for the Pristimantis myersi group.


Asunto(s)
Anuros , Evolución Biológica , Animales , Filogenia , ARN Ribosómico 16S , Anuros/genética , Colombia
5.
Trends Ecol Evol ; 38(7): 631-642, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36870806

RESUMEN

A recurring feature of oceanic archipelagos is the presence of adaptive radiations that generate endemic, species-rich clades that can offer outstanding insight into the links between ecology and evolution. Recent developments in evolutionary genomics have contributed towards solving long-standing questions at this interface. Using a comprehensive literature search, we identify studies spanning 19 oceanic archipelagos and 110 putative adaptive radiations, but find that most of these radiations have not yet been investigated from an evolutionary genomics perspective. Our review reveals different gaps in knowledge related to the lack of implementation of genomic approaches, as well as undersampled taxonomic and geographic areas. Filling those gaps with the required data will help to deepen our understanding of adaptation, speciation, and other evolutionary processes.


Asunto(s)
Evolución Biológica , Especiación Genética , Filogenia , Ecología , Genómica
6.
Evolution ; 77(2): 355-369, 2023 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-36611281

RESUMEN

The acoustic adaptation hypothesis (AAH) and ecological character displacement (ECD) are two potential mechanisms shaping call evolution that can predict opposite trends for the differentiation of signals. Under AAH, signals evolve to minimize environmental degradation and maximize detection against background noise, predicting call homogenization in similar habitats due to environmental constraints on signals. In contrast, ECD predicts greater differences in call traits of closely related taxa in sympatry because of selection against acoustic interference. We used comparative phylogenetic analyses to test the strength of these two selective mechanisms on the evolution of advertisement calls in glassfrogs, a highly diverse family of neotropical anurans. We found that, overall, acoustic adaptation to the environment may outweigh effects of species interactions. As expected under the AAH, temporal call parameters are correlated with vegetation density, but spectral call parameters had an unexpected inverse correlation with vegetation density, as well as an unexpected correlation with temperature. We detected call convergence among co-occurring species and also across multiple populations from the same species in different glassfrogs communities. Our results indicate that call convergence is common in glassfrogs, likely due to habitat filtering, while character displacement is relatively rare, suggesting that costs of signal similarity among related species may not drive divergent selection in all systems.


Asunto(s)
Ecosistema , Vocalización Animal , Animales , Filogenia , Anuros/genética , Acústica , Evolución Biológica
7.
Science ; 379(6630): eabo5003, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36701466

RESUMEN

Amazonian environments are being degraded by modern industrial and agricultural activities at a pace far above anything previously known, imperiling its vast biodiversity reserves and globally important ecosystem services. The most substantial threats come from regional deforestation, because of export market demands, and global climate change. The Amazon is currently perched to transition rapidly from a largely forested to a nonforested landscape. These changes are happening much too rapidly for Amazonian species, peoples, and ecosystems to respond adaptively. Policies to prevent the worst outcomes are known and must be enacted immediately. We now need political will and leadership to act on this information. To fail the Amazon is to fail the biosphere, and we fail to act at our peril.


Asunto(s)
Efectos Antropogénicos , Ecosistema , Bosques , Humanos , Biodiversidad , Conservación de los Recursos Naturales , Brasil
8.
Front Zool ; 20(1): 4, 2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36703215

RESUMEN

BACKGROUND: Large-scale species monitoring remains a significant conservation challenge. Given the ongoing biodiversity crisis, the need for reliable and efficient methods has never been greater. Drone-based techniques have much to offer in this regard: they allow access to otherwise unreachable areas and enable the rapid collection of non-invasive field data. Herein, we describe the development of a drone-based method for the estimation of population size in Galápagos marine iguanas, Amblyrhynchus cristatus. As a large-bodied lizard that occurs in open coastal terrain, this endemic species is an ideal candidate for drone surveys. Almost all Amblyrhynchus subspecies are Endangered or Critically Endangered according to the IUCN yet since several colonies are inaccessible by foot, ground- based methods are unable to address the critical need for better census data. In order to establish a drone-based approach to estimate population size of marine iguanas, we surveyed in January 2021 four colonies on three focal islands (San Cristobal, Santa Fe and Espanola) using three techniques: simple counts (the standard method currently used by conservation managers), capture mark-resight (CMR), and drone-based counts. The surveys were performed within a 4-day window under similar ambient conditions. We then compared the approaches in terms of feasibility, outcome and effort. RESULTS: The highest population-size estimates were obtained using CMR, and drone-based counts were on average 14% closer to CMR estimates-and 17-35% higher-than those obtained by simple counts. In terms of field-time, drone-surveys can be faster than simple counts, but image analyses were highly time consuming. CONCLUSION: Though CMR likely produces superior estimates, it cannot be performed in most cases due to lack of access and knowledge regarding colonies. Drone-based surveys outperformed ground-based simple counts in terms of outcome and this approach is therefore suitable for use across the range of the species. Moreover, the aerial approach is currently the only credible solution for accessing and surveying marine iguanas at highly remote colonies. The application of citizen science and other aids such as machine learning will alleviate the issue regarding time needed to analyze the images.

9.
Zookeys ; 1180: 257-293, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38312322

RESUMEN

The explosive diversity of rainfrogs (Pristimantis spp) reaches its highest levels in the mountains of the Tropical Andes, with remarkable cryptic species mainly in unexplored areas of Ecuador. Based on phylogenetics, morphometric traits, skull osteology and bioacoustics, we describe two new species of Pristimantis, previously confused with Pristimantisgladiator, that belong to the subgenus Trachyphrynus traditionally known as the Pristimantismyersi species group. The two new taxa are closely related, but have allopatric distributions. We discuss the importance of the Quijos and Pastaza River valleys in the diversification along Amazonian slopes of the Ecuadorian Andes.

10.
PeerJ ; 10: e14066, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36196397

RESUMEN

We have discovered a spectacular new species of frog in the genus Hyloscirtus, belonging to the H. larinopygion species group. The adult female is characterized by a mostly black body with large bright red spots on the dorsal and ventral surface, extremities, and toe pads. The adult male is unknown. Small juveniles are characterized by a yellow body with variable black markings on the flanks; while one larger juvenile displayed irregular orange or yellow marks on a black background color, with light orange or yellow toe pads. Additional distinctive external morphological features such as cloacal ornamentation are described, and some osteological details are imaged and analyzed. The performed phylogeny places the new species as the sister to a clade consisting of ten taxa, all of which are part of the H. larinopygion group. We use genetic distances to fit the new species into a published time-calibrated phylogeny of this group; our analysis based on the published chronology suggests that the divergence of the new species from its known congeners pre-dates the Quaternary period. The new species is currently only known only from Cerro Mayordomo, in Fundación EcoMinga´s Machay Reserve, at 2,900 m in the eastern Andes of Tungurahua province, Ecuador, near the southern edge of Los Llanganates National Park, but its real distribution may be larger.


Asunto(s)
Anuros , Parques Recreativos , Masculino , Femenino , Animales , Anuros/anatomía & histología , Ecuador , Distribución Animal , Filogenia
11.
Mol Ecol ; 31(24): 6440-6456, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36198047

RESUMEN

Widespread introduced species can be leveraged to investigate the genetic, ecological and adaptive processes underlying rapid evolution and range expansion, particularly the contributions of genetic diversity to adaptation. Rhinella marina, the cane toad, has been a focus of invasion biology for decades in Australia. However, their introduction history in North America is less clear. Here, we investigated the roles of introduction history and genetic diversity in establishment success of cane toads across their introduced range. We used reduced representation sequencing (ddRAD) to obtain 34,000 SNPs from 247 toads in native (French Guiana, Guyana, Ecuador, Panama, Texas) and introduced (Bermuda, southern Florida, northern Florida, Hawai'i, Puerto Rico) populations. Unlike all other cane toad introductions, we found that Florida populations were more closely related to native Central American lineages (R. horribilis), than to native Southern American lineages (R. marina). Furthermore, we found high levels of diversity and population structure in the native range, corroborating suggestions that R. marina is a species complex. We also found that introduced populations exhibit only slightly lower genetic diversity than native populations. Together with demographic analyses, this indicates founding populations of toads in Florida were larger than previously reported. Lastly, within R. marina, only one of 245 putatively adaptive SNPs showed fixed differences between native and introduced ranges, suggesting that putative selection in these introduced populations is based upon existing genetic variation. Our findings highlight the importance of genetic sequencing in understanding biological introductions and hint at the role of standing genetic variation in range expansion.


Asunto(s)
Variación Genética , Especies Introducidas , Animales , Bufo marinus/genética , Australia , Variación Genética/genética , Texas
12.
PeerJ ; 10: e13109, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35321409

RESUMEN

Background: The Tropical Andes is the world's most biodiverse hotspot. This region contains >1,000 amphibian species, more than half of which are endemic. Herein we describe two new glassfrog species (Centrolenidae: Hyalinobatrachium) that we discovered within relatively unexplored and isolated localities of the Ecuadorian Andes. Methods: We employed morphological, acoustic, and molecular methods to test the hypothesis that Hyalinobatrachium mashpi sp. nov and H. nouns sp. nov. are species new to science. Following standard methods, we generated mitochondrial sequences (16S) of 37 individuals in the genus Hyalinobatrachium. We inferred the phylogenetic relationships of the two new species in comparison to all other glassfrogs using Maximum Likelihood. In addition to describing the call of H. mashpi sp. nov., we performed a discriminant analysis of principal components (DAPC) with the advertisement call characteristics of several congeners. Results: Based on an integrative taxonomy approach, we describe two new species. Morphological traits and the inferred phylogeny unambiguously place the new taxa in the genus Hyalinobatrachium. Both species are distinguished from other glassfrogs mainly by their dorsal coloration (i.e., dorsum lime green with small light yellow spots, head usually with interorbital bar) and transparent pericardium (i.e., the heart is visible through the ventral skin). The new species exhibit a high morphological similarity (i.e., cryptic) and occur within relatively close geographical proximity (closest aerial distance = 18.9 km); however, their uncorrected p distance for the mitochondrial gene 16S is 4.6-4.7%, a value that greatly exceeds the genetic distance between closely related species of centrolenid frogs. The DAPC revealed that the advertisement call of H. mashpi sp. nov. is acoustically distinct. Discussion: Our findings are congruent with several previous studies that report a high degree of endemism in the Toisán mountain range, which appears to be isolated from the main Andean cordillera for some amphibian groups. We recommend that both H. mashpi sp. nov. and H. nouns sp. nov. be listed as Endangered, following IUCN criteria. These new species provide another example of cryptic diversity in the Andes-further evidence that the region fosters much more biodiversity than we have the resources to catalog. Threatened by mining and other exploitative industries, these glassfrogs and many other yet-to-be-discovered Andean species highlight the dire need for effective conservation measures-especially in northwestern Ecuador.


Asunto(s)
Anuros , Biodiversidad , Animales , Anuros/genética , Ecuador , Genes Mitocondriales , Filogenia
13.
Zookeys ; 1121: 175-210, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36760760

RESUMEN

The genus Atractus includes 146 species of cryptozoic snakes occurring from Panama to northeastern Argentina. Here, a molecular phylogeny of this genus is presented, which encompasses 29% (= 42; six are included here for the first time) of the species currently recognized. Morphological and phylogenetic support is found for three new species of ground snakes, which are described here based on their unique combination of molecular, meristic, and color pattern characteristics. The name A.arangoi Prado, 1939 is revalidated for a Colombian snake species previously subsumed under A.major Boulenger, 1894 based on new material collected in Ecuador. Reidentifications are provided for Atractus voucher specimens and sequences deposited in GenBank. With these changes, the number of Atractus reported in Ecuador increases from 27 to 31 species. Finally, attention is given to the importance of using a biogeographical framework that includes molecular data and a comprehensive geographic sampling when proposing species limits in complex taxonomic groups.

14.
PeerJ ; 9: e11914, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34434655

RESUMEN

We provide several lines of evidence to delimit a new species of Hyloscirtus and define its phylogenetic position inside the Hyloscirtus bogotensis group. The new species is the sister taxon to Hyloscirtus mashpi and is related to a clade formed by H. alytolylax and a putative new species from the province of El Oro in, southwestern Ecuador. Hyloscirtus conscientia sp. nov. is described from the montane forests of the Mira River basin in the extreme northwestern Ecuador. The new species is characterized as follows: tympanic annulus conspicuous, tip of snout in dorsal view subacuminate, middorsal stripe formed by melanophores larger and less dense, dorsal skin with individual iridophores forming dots, scarcely distributed across dorsum. Our study also highlights the importance of the Mira River Valley as a biogeographic barrier; suggesting research efforts north and south of the valley are likely to reveal additional endemic cryptic diversity. Finally, our partnership with Reserva: The Youth Land Trust, Rainforest Trust and EcoMinga Foundation has produced a novel and meaningful way to connect young people with biodiversity discovery and habitat conservation.

15.
Sci Rep ; 11(1): 14959, 2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34294756

RESUMEN

Shark fishing, driven by the fin trade, is the primary cause of global shark population declines. Here, we present a case study that exemplifies how industrial fisheries are likely depleting shark populations in the Eastern Tropical Pacific Ocean. In August 2017, the vessel Fu Yuan Yu Leng 999, of Chinese flag, was detained while crossing through the Galápagos Marine Reserve without authorization. This vessel contained 7639 sharks, representing one of the largest seizures recorded to date. Based on a sample of 929 individuals (12%), we found 12 shark species: 9 considered as Vulnerable or higher risk by the IUCN and 8 listed in CITES. Four species showed a higher proportion of immature than mature individuals, whereas size-distribution hints that at least some of the fishing ships associated with the operation may have been using purse-seine gear fishing equipment, which, for some species, goes against international conventions. Our data expose the magnitude of the threat that fishing industries and illegal trade represent to sharks in the Eastern Tropical Pacific Ocean.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Tiburones/anatomía & histología , Tiburones/crecimiento & desarrollo , Animales , Tamaño Corporal , Conservación de los Recursos Naturales , Explotaciones Pesqueras , Océano Pacífico , Conducta Sexual Animal , Tiburones/clasificación , Tiburones/genética
16.
PLoS One ; 16(5): e0251027, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33956885

RESUMEN

Ecuador is one of the most biodiverse countries in the world, but faces severe pressures and threats to its natural ecosystems. Numerous species have declined and require to be objectively evaluated and quantified, as a step towards the development of conservation strategies. Herein, we present an updated National Red List Assessment for amphibian species of Ecuador, with one of the most detailed and complete coverages for any Ecuadorian taxonomic group to date. Based on standardized methodologies that integrate taxonomic work, spatial analyses, and ecological niche modeling, we assessed the extinction risk and identified the main threats for all Ecuadorian native amphibians (635 species), using the IUCN Red List Categories and Criteria. Our evaluation reveals that 57% (363 species) are categorized as Threatened, 12% (78 species) as Near Threatened, 4% (26 species) as Data Deficient, and 27% (168 species) as Least Concern. Our assessment almost doubles the number of threatened species in comparison with previous evaluations. In addition to habitat loss, the expansion of the agricultural/cattle raising frontier and other anthropogenic threats (roads, human settlements, and mining/oil activities) amplify the incidence of other pressures as relevant predictors of ecological integrity. Potential synergic effects with climate change and emergent diseases (apparently responsible for the sudden declines), had particular importance amongst the threats sustained by Ecuadorian amphibians. Most threatened species are distributed in montane forests and paramo habitats of the Andes, with nearly 10% of them occurring outside the National System of Protected Areas of the Ecuadorian government. Based on our results, we recommend the following actions: (i) An increase of the National System of Protected Areas to include threatened species. (ii) Supporting the ex/in-situ conservation programs to protect species considered like Critically Endangered and Endangered. (iii) Focalizing research efforts towards the description of new species, as well as species currently categorized as Data Deficient (DD) that may turn out to be threatened. The implementation of the described actions is challenging, but urgent, given the current conservation crisis faced by amphibians.


Asunto(s)
Anfibios , Especies en Peligro de Extinción , Animales , Anuros , Bufonidae , Conservación de los Recursos Naturales/métodos , Bases de Datos como Asunto , Ecosistema , Ecuador , Especies en Peligro de Extinción/estadística & datos numéricos
17.
Ecotoxicol Environ Saf ; 215: 112122, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33725489

RESUMEN

The human ingestion of mercury (Hg) from sea food is of big concern worldwide due to adverse health effects, and more specifically if shark consumption constitutes a regular part of the human diet. In this study, the total mercury (THg) concentration in muscle tissue were determined in six sympatric shark species found in a fishing vessel seized in the Galapagos Marine Reserve in 2017. The THg concentrations in shark muscle samples (n = 73) varied from 0.73 mg kg-1 in bigeye thresher sharks (Alopias superciliosus) to 8.29 mg kg-1 in silky sharks (Carcharhinus falciformis). A typical pattern of Hg bioaccumulation was observed for all shark species, with significant correlation between THg concentration and shark size for bigeye thresher sharks, pelagic thresher sharks (Alopias pelagicus) and silky sharks. Regarding human health concerns, the THg mean concentration exceeded the maximum weekly intake fish serving in all the studied species. Mass-Dependent Fractionation (MDF, δ202Hg values) and Mass-Independent Fractionation (MIF, Δ199Hg values) of Hg in whitetip sharks (Carcharhinus longimanus) and silky sharks, ranged from 0.70‰ to 1.08‰, and from 1.97‰ to 2.89‰, respectively. These high values suggest that both species are feeding in the epipelagic zone (i.e. upper 200 m of the water column). While, blue sharks (Prionace glauca), scalloped hammerhead sharks (Shyrna lewini) and thresher sharks were characterized by lower Δ199Hg and δ202Hg values, indicating that these species may focus their foraging behavior on prey of mesopelagic zone (i.e. between 200 and 1000 m depth). In conclusion, the determination of THg concentration provides straight-forward evidence of the human health risks associated with shark consumption, while mercury isotopic compositions constitute a powerful tool to trace the foraging strategies of these marine predators. CAPSULE: A double approach combining Hg concentrations with stable isotopes ratios allowed to assess ontogeny in common shark species in the area of the Galapagos Marine Reserve and the human health risks concern associated to their consumption.


Asunto(s)
Mercurio/metabolismo , Tiburones/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Bioacumulación , Monitoreo del Ambiente/métodos , Conducta Alimentaria , Humanos , Isótopos , Mercurio/análisis , Isótopos de Mercurio , Músculos/química , Alimentos Marinos , Tiburones/fisiología , Contaminantes Químicos del Agua/análisis
18.
Sci Rep ; 11(1): 1386, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33446869

RESUMEN

Parental care is costly, thus theory predicts that parents should avoid caring for unrelated offspring. However, alloparenting has been reported in many taxa because it may increase the caregiver mating success or offspring survival. We experimentally investigated the existence of allopaternal care in two glassfrog species, Hyalinobatrachium chirripoi and Centrolene peristicta, and discussed possible costs and benefits. Males mated with multiple females and cared for clutches, while continued to call. In the field, we randomly placed unrelated clutches in the territory of males already caring for their clutches and in the territory of non-attending males. Attending males adopted unrelated clutches, whereas non-attending males abandoned their territories. Once males adopted unrelated offspring, they cared for all clutches in a similar frequency and gained new clutches. Alloparenting was context-dependent, as only males already caring for their clutches adopted unrelated ones. We suggest that steroid hormonal levels might mediate the adoption of unrelated offspring by attending males. Additionally, our results suggest that males do not directly discriminate between related and unrelated offspring. Alloparenting has been widely investigated in different vertebrates, except for amphibians. Thus, our study sheds light on the roles of alloparenting for offspring survival and mating success in this group.


Asunto(s)
Anuros/fisiología , Conducta Sexual Animal/fisiología , Animales , Masculino , Reproducción/fisiología
19.
Glob Chang Biol ; 27(2): 297-311, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33064866

RESUMEN

A fundamental gap in climate change vulnerability research is an understanding of the relative thermal sensitivity of ectotherms. Aquatic insects are vital to stream ecosystem function and biodiversity but insufficiently studied with respect to their thermal physiology. With global temperatures rising at an unprecedented rate, it is imperative that we know how aquatic insects respond to increasing temperature and whether these responses vary among taxa, latitudes, and elevations. We evaluated the thermal sensitivity of standard metabolic rate in stream-dwelling baetid mayflies and perlid stoneflies across a ~2,000 m elevation gradient in the temperate Rocky Mountains in Colorado, USA, and the tropical Andes in Napo, Ecuador. We used temperature-controlled water baths and microrespirometry to estimate changes in oxygen consumption. Tropical mayflies generally exhibited greater thermal sensitivity in metabolism compared to temperate mayflies; tropical mayfly metabolic rates increased more rapidly with temperature and the insects more frequently exhibited behavioral signs of thermal stress. By contrast, temperate and tropical stoneflies did not clearly differ. Varied responses to temperature among baetid mayflies and perlid stoneflies may reflect differences in evolutionary history or ecological roles as herbivores and predators, respectively. Our results show that there is physiological variation across elevations and species and that low-elevation tropical mayflies may be especially imperiled by climate warming. Given such variation among species, broad generalizations about the vulnerability of tropical ectotherms should be made more cautiously.


Asunto(s)
Ephemeroptera , Animales , Colorado , Ecosistema , Ecuador , Insectos , Temperatura , Clima Tropical
20.
Zootaxa ; 4820(1): zootaxa.4820.1.10, 2020 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-33056088

RESUMEN

Taxon names are at the core of communication related to biodiversity. Thus, systems that regulate such names should prevent unnecessary changes. Unfortunately, the current regulatory codes have some articles that produce confusion or, even, generate name instability. To promote nomenclatural stability, while maintaining a system that effectively conveys information about biological diversity and its evolution, we argue in favor of emendations to the current International Code of Zoological Nomenclature (ICZN). We propose that taxon names should be created within an evolutionary framework; ideally, this would mean including a phylogenetic tree or, at the very least, formulating a hypothesis in words based on explicit arguments (homologous traits) for the evolutionary relatedness of taxa, avoiding subjective perceptions. Additionally, we consider that some relatively minor changes of the ICZN would greatly increase name stability; the most relevant modifications that would facilitate long-term stability are: (i) immutability of the species epithet of species names, (ii) intercalation of unranked taxa between formal Linnaean ranks, (iii) elimination of homonyms in taxon names at the genus-group level, and (iv) inclusion of flexible phylogenetic definitions when supraspecific taxa are named.


Asunto(s)
Biodiversidad , Terminología como Asunto , Animales , Fenotipo , Filogenia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...