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1.
Evolution ; 74(8): 1815-1825, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32510580

RESUMO

Many animals breed exclusively in plants that accumulate rainwater (phytotelma; e.g., bromeliad, bamboo, fruit husk, and tree hole), to which they are either physiologically or behaviorally specialized for this microhabitat. Of the numerous life-history modes observed in frogs, few are as striking or potentially consequential as the transition from pond- or stream-breeding to the deposition of eggs or larvae in phytotelmata. Such specialization can increase offspring survivorship due to reduced competition and predation, representing potential ecological opportunity for adaptive radiation, yet few lineages of phytotelma-breeding frogs appear to have diversified extensively after such a transition, at least in the New World. We use a phylogeny of Neotropical frogs and data on breeding microhabitat to understand the evolutionary transitions involved with specialized phytotelma-breeding. First, we find that phytotelma-breeding is present in at least 168 species in 10 families of frogs. Across the phylogeny, we estimate 14 origins of phytotelma-breeding and 115 reversals, showing that phytotelma-breeding is a highly labile character. Second, phytotelma-breeding lineages overall have higher net diversification than nonphytotelma-breeding ones. This specialization represents an ecological opportunity resulting in increased diversification in most families with phytotelma-breeding lineages, whereas phytotelma-breeding toads have restricted diversification histories.


Assuntos
Anuros/genética , Evolução Biológica , Ecossistema , Reprodução , América , Animais , Modelos Genéticos
2.
Ecol Evol ; 10(8): 3686-3695, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32313627

RESUMO

Allometric constraint is a product of natural selection and physical laws, particularly with respect to body size and traits constrained by properties thereof, such as metabolism, longevity, and vocal frequency. Allometric relationships are often conserved across lineages, indicating that physical constraints dictate scaling patterns in deep time, despite substantial genetic and ecological divergence among organisms. In particular, acoustic allometry (sound frequency ~ body size) is conserved across frogs, in defiance of massive variation in both body size and frequency. Here, we ask how many instances of allometric escape have occurred across the frog tree of life using a Bayesian framework that estimates the location, number, and magnitude of shifts in the adaptive landscape of acoustic allometry. Moreover, we test whether ecology in terms of calling site could affect these relationships. We find that calling site has a major influence on acoustic allometry. Despite this, we identify only four major instances of allometric escape, potentially deriving from ecomorphological adaptations to new signal modalities. In these instances of allometric escape, the optima and strength of the scaling relationship are different than expected for most other frog species, representing new adaptive regimes of body size ~ call frequency. Allometric constraints on frog calls are highly conserved and have rarely allowed escape, despite frequent invasions of new adaptive regimes and dramatic ecomorphological divergence. Our results highlight the rare instances in which natural and sexual selection combined can overcome physical constraints on sound production.

3.
Zookeys ; 857: 139-162, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303808

RESUMO

A checklist of the amphibians of Santa Teresa municipality, in southeastern Brazil is presented based on fieldwork, examination of specimens in collections, and a literature review. This new amphibian list of Santa Teresa includes 108 species, of which 106 (~98%) belong to Anura and two (~2%) to Gymnophiona. Hylidae was the most represented family with 47 species (43%). Compared to the previous amphibian lists for Santa Teresa, 14 species were added, 17 previously reported species were removed, and 13 species were re-identified based on recent taxonomic rearrangements. Of the 14 species added, 11 (79%) were first recorded during our fieldwork and specimen examination. It is also the first list of caecilians for Santa Teresa. This list suggests that Santa Teresa has 0.16 species per km2 (i.e., 108 species/683 km2), one of the highest densities of amphibian species in the world at a regional scale. This richness represents 78% of the 136 anurans from Espírito Santo state and 10% of the 1,080 amphibians from Brazil. We highlight the need for long-term monitoring to understand population trends and develop effective conservation plans to safeguard this remarkable amphibian richness.

5.
Mol Phylogenet Evol ; 130: 198-210, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30347238

RESUMO

Chiasmocleis is the most species-rich genus of Neotropical microhylids. Herein, we provide the first comprehensive multilocus phylogeny for the genus, including all but 3 of the 34 recognized species and multiple individuals per species. We discuss cryptic speciation, species discovery, patterns of morphological evolution, and provide a historical biogeographic analysis to account for the current distribution of the genus. Diversification of Chiasmocleis from other New World microhylids began during the Eocene, app. 40 mya, in forested areas, and current diversity seems to be a product of recurrent connections between the Atlantic Forest and Amazonia. Small-sized species evolved independently three times in Chiasmocleis. Furthermore, the extremely small-bodied (i.e. miniaturized) species with associated loss of digits, phalanges, and pectoral girdle cartilages evolved only once and are restricted to Amazonia. Using the phylogeny, we recognized three subgenera within Chiasmocleis: Chiasmocleis Méhely, 1904, Relictus subg. nov., and Syncope Walker, 1973. The recognition of the subgenus Syncope informs future research on patterns of miniaturization in the genus, and the subgenus Relictus highlights isolation of an endemic and species-poor lineage to the Atlantic Forest, early (about 40 mya) in the history of Chiasmocleis.


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Florestas , Filogenia , Animais , Anuros/genética , Brasil
6.
Biota neotrop. (Online, Ed. port.) ; 10(3): 339-351, jul.-set. 2010.
Artigo em Inglês | LILACS | ID: lil-567880

RESUMO

Reserva Biológica de Duas Bocas (2,910 ha) is one of the largest Atlantic forest remnants in the State of Espírito Santo, Southeastern Brazil. We recorded non-volant tetrapods in this area from May 2007 through April 2008, using pitfalls, live traps, camera traps, and diurnal and nocturnal opportunistic searches. In addition, we compiled available museum and literature records from this area. We documented 52 species of amphibians, 24 species of non-avian reptiles, and 39 species of non-volant mammals. Out of these 115 species, 47 are new records for this area and six other species had their geographic ranges expanded with the present study. Furthermore, we present the record of predation of the tree frog Hypsiboas faber by the snake Chironius bicarinatus. Out of the species listed, five species are listed as threatened with extinction in the State of Espírito Santo, and many others have uncertain conservation status. Reserva Biológica de Duas Bocas is an important wildlife refuge, especially considering the expansion of urban areas in its surroundings.


A Reserva Biológica de Duas Bocas (2.190 ha) é um dos maiores remanescentes de Mata Atlântica do Estado do Espírito Santo, Sudeste do Brasil. Nós amostramos tetrápodes não voadores nessa área entre maio de 2007 e abril de 2008, utilizando armadilhas de queda, armadilhas de isca, armadilhas fotográficas e buscas oportunísticas diurnas e noturnas. Além disso, nós compilamos registros de vertebrados não voadores ocorrentes nesta área disponíveis na literatura e através de espécimes em museus. Nós documentamos 52 espécies de anfíbios, 24 espécies de répteis não voadores e 39 espécies de mamíferos não voadores. Do total de 115 espécies, 47 configuram novos registros para a área e seis outras espécies tiveram sua distribuição geográfica ampliada com os resultados do presente estudo. Além disso, apresentamos o registro de predação da perereca Hypsiboas faber pela serpente Chironius bicarinatus. Cinco das espécies registradas são listadas como ameaçadas no Estado do Espírito Santo e muitas outras possuem estado de conservação incerto. A Reserva Biológica de Duas Bocas é um importante refúgio de vida selvagem, principalmente quando consideramos a expansão de áreas urbanas no seu entorno.

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