{"id":3609,"date":"2020-03-05T08:30:42","date_gmt":"2020-03-05T11:30:42","guid":{"rendered":"https:\/\/www.ufrgs.br\/ppgban\/?p=3609"},"modified":"2020-03-05T08:34:58","modified_gmt":"2020-03-05T11:34:58","slug":"estudo-do-ppgban-publicado-no-periodico-journal-of-zoology","status":"publish","type":"post","link":"https:\/\/www.ufrgs.br\/ppgban\/estudo-do-ppgban-publicado-no-periodico-journal-of-zoology\/","title":{"rendered":"Estudo do PPGBAN publicado no peri\u00f3dico Journal of Zoology"},"content":{"rendered":"\n

Um estudo do grupo de Pesquisas PPGBAN DEZOO foi publicado essa semana no peri\u00f3dico Journal of Zoology<\/a> e ilustrou a capa da edi\u00e7\u00e3o. O estudo foi tema da disserta\u00e7\u00e3o de mestrado da Nat\u00e1lia Vargas e a foto de capa foi da nossa ex-aluna Valentina Caorsi. Confira abaixo o v\u00eddeo de divulga\u00e7\u00e3o, explicando o estudo, assim como algumas fotos e o texto explicativo encaminhado para o Journal of Zoology e que ser\u00e1 usado no Blog do peri\u00f3dico:<\/p>\n\n\n\n

Visualizar o v\u00eddeo Como o sapinho-verde-de-barriga-vermelha\nevita predadores? do YouTube<\/a><\/p>\n\n\n\n

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Anti-predator coloration in\nred-bellied toads: a new experimental test of long-accepted ideas<\/strong><\/p>\n\n\n\n

Crypsis and aposematism are\nimportant forms of anti-predatory strategies. Through cryptic coloration,\nanimals reduce their detectability by matching the coloration of backgrounds,\nwhile through aposematic coloration, prey species signal to potential predators\ntheir unprofitability by conspicuous coloration. Among amphibians, both\nstrategies are well known.<\/p>\n\n\n\n

The Neotropical red-bellied toads (Melanophryniscus<\/em>\nspp.) are small bufonids restricted to subtropical and tropical South America.\nMost of the 29 species of this genus have naturally restricted distributions.\nThese small toads are rare or difficult to find and are usually recorded only\nduring reproductive events. They\u2019re explosive breeders, so reproduction occurs\nover a short period of time in temporary ponds and streams after heavy rains.\nRed-bellied toads are diurnal, unlike most anuran species, and have alkaloids\nas chemical defenses. Alkaloids are sequestered from their diet, rich in ants\nand Acari.<\/p>\n\n\n\n

Most red-bellied toad species\npresent conspicuous coloration, usually with red, orange or yellow marks,\nagainst a dark background. Conspicuous coloration may be present both dorsally\nand ventrally. Moreover, they display these conspicuous ventral colors to\npotential predators in a weird and poorly understood behavior known as the\nunken reflex. In this behavior, the toads arch the body and raise the head and\nthe posterior region, exhibiting the ventral conspicuous colors.<\/p>\n\n\n\n

The unken reflex and the conspicuous\ncolors have been customarily regarded as warning signals to avoid or reduce\npredation attempts by visually oriented predators. Although these toads\nrepresent an appealing model to study many unanswered aspects of aposematic\nsignal evolution, such as the mechanistic basis of aposematic markings and the\nform and diversity of warning signals, almost nothing was experimentally\nexplored.<\/p>\n\n\n\n

A team of students and researchers, in the Laboratory of Herpetology at Federal University of Rio Grande do Sul, Brazil, have studied many aspects of the ecology and natural history of some threatened species of red-bellied-toads. In an attempt to test the effects of coloration and the unken reflex on predation rates, a series of experiments has been conducted with Melanophryniscus cambaraensis<\/em>.<\/p>\n\n\n\n

The tiny Cambar\u00e1\u2019s red-bellied toad,\nMelanophryniscus cambaraensis<\/em>, is endemic to a restricted area in the\nAtlantic Forest of southern Brazil. It is a threatened species, officially\nlisted as Vulnerable in Brazil. Only two populations have been found in the\nhighlands of the Araucaria Plateau, and one of them has probably gone extinct\nin the 1990s. The main threats are habitat loss and fragmentation, but the\nreasons for the extinction of one of the populations are unknown. This green\nred-bellied toad is one of the three species of the genus with green dorsal\ncoloration.<\/p>\n\n\n\n

In the study recently published in\nthe Journal of Zoology, the team evaluated experimentally if the green dorsal\ncolor of Melanophryniscus cambaraensis<\/em> functions as warning coloration\nfor visually oriented natural predators. Field predation experiments were\nconducted using clay models, representing M. cambaraensis<\/em> (noxious,\ngreen models) and a generalized cryptic frog (palatable, brown models), to\ncompare attack rates.<\/p>\n\n\n\n

The avian attacks were concentrated mainly on the anterior end, suggesting models were perceived as prey. However, attack rates were similar on green and brown frog models. Our results suggest that the green dorsal color of the species does not act as an aposematic signal, but functions as a cryptic color. Although crypsis in poisonous species remains a complex topic, under certain circumstances, the selection pressures imposed by predators may favor a cryptic coloration instead of a conspicuous coloration, even for diurnal species.<\/p>\n\n\n\n

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Um estudo do grupo de Pesquisas PPGBAN DEZOO foi publicado essa semana no peri\u00f3dico Journal of Zoology e ilustrou a capa da edi\u00e7\u00e3o. O estudo foi tema da disserta\u00e7\u00e3o de mestrado da Nat\u00e1lia Vargas e a foto de capa foi da nossa ex-aluna Valentina Caorsi. Confira abaixo o v\u00eddeo de divulga\u00e7\u00e3o, explicando o estudo, assim … <\/p>\n

Continue lendo “Estudo do PPGBAN publicado no peri\u00f3dico Journal of Zoology”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_joinchat":[]},"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/posts\/3609"}],"collection":[{"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/comments?post=3609"}],"version-history":[{"count":2,"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/posts\/3609\/revisions"}],"predecessor-version":[{"id":3617,"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/posts\/3609\/revisions\/3617"}],"wp:attachment":[{"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/media?parent=3609"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/categories?post=3609"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ufrgs.br\/ppgban\/wp-json\/wp\/v2\/tags?post=3609"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}