Search results for " Amphibian"

Is the painted frog Discoglossus pictus a declining species in Italy? On the reliability of a distributional atlas approach

2013

The conservation status of amphibians is often assessed using public databases because of a lack of up-to-date field data. However, it is crucial that this kind of data is used carefully, evaluating the reliability and the consistency of the information. In Italy, the conservation status of the painted frog, Discoglossus pictus, was recently assessed using public databases, and the outcome highlighted a worrying situation for the species. We analyzed the reliability of these conclusions and reassessed the status of the painted frog, taking into account its insular distribution and new data of species occurrence. Our results contrast with the previous analysis and show how an incautious use …

Influenza del dimorfismo comportamentale nella stima della grandezza di popolazione. Il caso di Bufo viridis.

2007

Differenze sessuali nell'utilizzo spazio-temporale del territorio in una popolazione di Bufo viridis in Sicilia

2006

Contrasting parental roles shape sex differences in poison frog space use but not navigational performance

2022

Sex differences in vertebrate spatial abilities are typically interpreted under the adaptive specialization hypothesis, which posits that male reproductive success is linked to larger home ranges and better navigational skills. The androgen spillover hypothesis counters that enhanced male spatial performance may be a byproduct of higher androgen levels. Animal groups that include species where females are expected to outperform males based on life-history traits are key for disentangling these hypotheses. We investigated the association between sex differences in reproductive strategies, spatial behavior, and androgen levels in three species of poison frogs. We tracked individuals in natura…

Contribute to the knowledge of Tunisian amphibians: Notes on distribution, habitat features and phenology

2007

Bezastaino abinieku Anura sugu sastāvs un izplatība pilsētvides ūdenstilpēs Daugavpilī

2022

Mūsdienās abinieki pasaulē ir viena no visvairāk apdraudētām dzīvnieku klasēm. Visos pasaules reģionos ir konstatēta īpatņu skaita samazināšanās vai pilnīga izzušana. Abinieku izmiršanas cēloņi ir dažādi – biotopu pārveidošana, klimata izmaiņas, kā arī sēnīšu Batrachochytrium dendrobatidis izraisīta slimība. Abinieku izzušana ir skaidri redzama pateicoties bezastainajiem abiniekiem, jo tos var viegli gan ieraudzīt, gan saklausīt. Diemžēl šī problēma varētu skart arī Latvijas abiniekus. Bakalaura darba mērķis ir noteikt, kādas bezastaino abinieku sugas ir sastopamas Daugavpils ūdenstilpēs, kā arī noteikt aptuveno populācijas lielumu, pamatojoties uz pieaugušo varžu un krupju tēviņu dziesmu i…

Context dependent variation in corticosterone and phenotypic divergence of Rana arvalis populations along an acidification gradient

2022

Background Physiological processes, as immediate responses to the environment, are important mechanisms of phenotypic plasticity and can influence evolution at ecological time scales. In stressful environments, physiological stress responses of individuals are initiated and integrated via the release of hormones, such as corticosterone (CORT). In vertebrates, CORT influences energy metabolism and resource allocation to multiple fitness traits (e.g. growth and morphology) and can be an important mediator of rapid adaptation to environmental stress, such as acidification. The moor frog, Rana arvalis, shows adaptive divergence in larval life-histories and predator defense traits along an acidi…

A catalogue of the vertebrate fossil record from the Guadix-Baza Basin (SE Spain)

2020

In this paper, a catalogue of the vertebrate content of the Guadix-Baza Basin is presented. A total of 93 localities have been reviewed, providing more than 300 vertebrate species. These localities have been included in 11 biochronological units, ranging in age from the late Miocene (MN 13) to the Middle Pleistocene (MmQ 4), including also two MN 10 localities. The best-represented epoch in the Guadix-Baza Basin is the Pliocene (MN 14 to MN 16), with 41 sites. This is followed by the Early Pleistocene (MN17 and MmQ1 to MmQ3) with 30 sites. The vertebrate classes represented in the basin are Actinopterygii, Amphibia, Aves, Reptilia and Mammalia, this last one being the best represented. Amon…