{"id":519114,"date":"2024-08-20T14:45:39","date_gmt":"2024-08-20T17:45:39","guid":{"rendered":"https:\/\/revistapesquisa.fapesp.br\/?p=519114"},"modified":"2024-08-20T14:45:39","modified_gmt":"2024-08-20T17:45:39","slug":"underground-amphibians-produce-milk-to-feed-their-young","status":"publish","type":"post","link":"https:\/\/revistapesquisa.fapesp.br\/en\/underground-amphibians-produce-milk-to-feed-their-young\/","title":{"rendered":"Underground amphibians produce \u201cmilk\u201d to feed their young"},"content":{"rendered":"

In mid-2007, a film crew from the British BBC visited the Butantan Institute in S\u00e3o Paulo to capture footage of amphibians for its series Life in cold blood<\/em>. During filming, one scene was intriguing: recently born caecilia\u2014commonly known as blind snakes, although more similar in appearance to frogs\u2014gathering around the mother\u2019s cloacal opening. It was already known that the offspring feeds from a layer of maternal skin during the first months of life, but the behavior captured by the documentary aroused curiosity: what were those newborns seeking out in the opening from which they had emerged?<\/p>\n

A team of researchers from the Butantan Institute identified the possible answer 17 years later: the offspring of Siphonops annulatus<\/em> are \u201cbreastfed\u201d daily with a kind of milk. \u201cThe mother lifts her tail and the young suckle a slightly viscous liquid expressed from the cloacal opening,\u201d explains biologist Carlos Jared, of the Butantan Structural Biology Laboratory, author of the article describing these findings in the March edition of Science<\/em>. \u201cWe collected and analyzed this liquid, and found that it has components similar to those of mammals\u2019 milk,\u201d says the researcher, who supervised the postdoctoral study that led to the discovery. The article goes on to describe how the young make a sound a few minutes before being fed, which may indicate their asking for food.<\/p>\n

Few nonmammal species present this type of behavior. There are records of breastfeeding by certain types of spider, roach, fish, and birds, but the phenomenon had never been registered in egg-laying amphibians such as caecilias. The milk identified by the Butantan researchers largely comprises lipids and carbohydrates, and is secreted by glands that expand during the early parental care period of two to three months. \u201cWe cannot call them mammary glands, because the evolutionary origins are different, but this demonstrates how caecilias have adapted in different ways to survive over time,\u201d says Jared.<\/p>\n

To confirm their understanding of the phenomenon, the group filmed the behavior of 16 caecilia females for 242 hours over six years. The animals studied were collected in Ilh\u00e9us in northeastern Brazil\u2019s Bahia State, a cocoa-growing region where blind snakes are commonly found underground. \u201cAs their environment is difficult to access, this is one of the lesser-known vertebrate groups in science,\u201d says biologist Tam\u00ed Mott, of the Federal University of Alagoas (UFAL), one of few Brazilian specialists in these animals. Worldwide, 222 species of caecilia are known, of which some 20% (39) are found in Brazil. This type of animal is typical of tropical regions and depends on having moist skin, through which much of its breathing takes place.<\/p>\n

They were described for the first time in 1822, and the Butantan group is a pioneer in the long-term study of caecilias, having discovered that the species has a poison gland at the base of its teeth, and is capable of inoculating with its bite. In 2006 the team also published an article in the journal Nature<\/em> demonstrating how the young eat pieces of the mother\u2019s external skin, modified during this early parental care period. This behavior, known as dermatophagia, or skin-feeding, has been identified in another caecilia species.<\/p>\n

Footage of breastfeeding, however, is unprecedented, as is the sound made by the young. \u201cThere are reports of communication as a form of defense in some species, but during early parental care this is a spectacular finding,\u201d comments Mott. For her, this work opens doors to new fronts of investigation into the evolution of these enigmatic amphibians.<\/p>\n

Projects<\/strong>
\n1.<\/strong> Unraveling parental care in caecilians: Nutritional and toxinological implications in Siphonops annulatus<\/em> (n\u00ba 18\/03265-9<\/a>); Grant Mechanism<\/strong> Regular Research Grant; Principal Investigator<\/strong> Carlos Alberto Gon\u00e7alves Silva Jared (Instituto Butantan); Investment<\/strong> R$175,382.65.
\n2.<\/strong> Parental care and dermatophagy in the ringed caecilian Siphonops annulatus<\/em>: An integrative approach (n\u00ba 17\/10488-1<\/a>); Grant Mechanism<\/strong> Postdoctoral fellowship; Supervisor<\/strong> Carlos Alberto Gon\u00e7alves Silva Jared (Instituto Butantan); Beneficiary<\/strong> Pedro Luiz Mailho Fontana; Investment<\/strong> R$310,331.44.<\/p>\n

Scientific articles<\/strong>
\nMAILHO-FONTANA, P. L. et al<\/em>. Milk provisioning in oviparous caecilian amphibians<\/a>. Science<\/strong>. Online. Mar. 8, 2024.
\nKUPFER, A. M. et al.<\/em> Parental investment by skin feeding in a caecilian amphibian<\/a>. Nature<\/strong>. Vol. 440, pp. 926\u20139. Apr. 13, 2006.<\/p>\n","protected":false},"excerpt":{"rendered":"Study published in Science<\/em> describes nursing behavior in caecilian species found in Brazil","protected":false},"author":721,"featured_media":519116,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[159],"tags":[218,266],"coauthors":[4241],"class_list":["post-519114","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-science","tag-ethology","tag-zoology"],"acf":[],"_links":{"self":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/519114","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/users\/721"}],"replies":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/comments?post=519114"}],"version-history":[{"count":1,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/519114\/revisions"}],"predecessor-version":[{"id":519136,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/519114\/revisions\/519136"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media\/519116"}],"wp:attachment":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media?parent=519114"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/categories?post=519114"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/tags?post=519114"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/coauthors?post=519114"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}