{"id":235313,"date":"2017-03-27T18:11:34","date_gmt":"2017-03-27T21:11:34","guid":{"rendered":"http:\/\/revistapesquisa.fapesp.br\/en\/?p=235313"},"modified":"2017-03-28T16:35:42","modified_gmt":"2017-03-28T19:35:42","slug":"the-foxes-of-the-americas","status":"publish","type":"post","link":"https:\/\/revistapesquisa.fapesp.br\/en\/the-foxes-of-the-americas\/","title":{"rendered":"The foxes of the Americas"},"content":{"rendered":"
\"Hoary

Cintia Possas<\/span><\/a> Pampas fox and hoary fox (photo<\/em>) procreate in the state of S\u00e3o PauloCintia Possas<\/span><\/p><\/div>\n

There are species of fox scattered across every continent except the Antarctic, but foxes enjoy little popularity in Brazil. It\u2019s not that they have a bad reputation: their existence actually goes nearly unnoticed, despite the fact that they are often run over by vehicles in the streets. Even biologists do not usually pay them much heed. But the group led by geneticist Eduardo Eizirik of the Pontifical Catholic University of Rio Grande do Sul (PUC-RS) has started reconstructing the history of the diversification of these animals in South America, and showing how changes in the environment can genetically affect these species\u2014although it is uncertain whether these changes are problematic for the animals.<\/p>\n

According to a paper published in the July\/September issue of the journal Genetics and Molecular Biology<\/em>, the hoary fox (Lycalopex vetulus<\/em>) was the first species of this group of canids to exhibit evolutionary divergence from the North American lineages, between 1 and 1.3 million years ago, after a common ancestor moved southward across the Isthmus of Panama. Of the eight species of South American foxes, it is the only one endemic to Brazil, inhabiting all areas of the Cerrado savannah, and thus accustomed to open landscapes. Analyses conducted by geneticist Ligia Tchaicka as part of her doctoral research under Thales de Freitas of the Federal University of Rio Grande do Sul (UFRGS), with Eizirik as co-advisor, show that the emergence and diversification of the genus Lycalopex<\/em> occurred after the species had entered South America.<\/p>\n

This conclusion fits in with the theory developed by other groups, which posits that a rise in sea level split South America into two parts during the Pleistocene. The split likely left one group in eastern Brazil, giving rise to the hoary fox, and the other in western Brazil, where it expanded into the Andes region and diversified there, giving rise to the other species.<\/p>\n

Hybrids<\/strong>
\nWhen she compared the genetic material from five species of South American foxes, Tchaicka, now a professor at the State University of Maranh\u00e3o (UEMA), saw another enigma: some individuals that had been classified as Pampas fox (L. gymnocercus<\/em>)\u2014which is typical of southern Brazil, as well as Uruguay, Argentina, Paraguay and Bolivia\u2014had mitochondrial DNA (received only from the mother) more similar to the South American gray fox, L. griseus<\/em>, which is widely distributed throughout Chile and Argentina\u2014on the other side of the Andes. One possible explanation would be that these foxes are really hybrids\u2014a surprising conclusion since, despite the overlapping distributions of the two species, there are no records of places where they both exist.<\/p>\n

More recent but as-yet-unpublished studies have pointed to another locus of hybridization, in this case between the Pampas fox and the hoary fox, in the state of S\u00e3o Paulo. \u201cWith the gradual disappearance of the Atlantic Forest, the fox has been occupying open areas and expanding its distribution outside the domain of the Cerrado,\u201d Eizirik explains. \u201cWe had already conceived of the possibility that it could end up encountering the Pampas fox.\u201d The formation of hybrids is nothing new to Eizirik, who has found similar results in wild cats (see Pesquisa FAPESP <\/em>Issue n\u00ba 159<\/a>).<\/p>\n

That is precisely what has been shown by the work of biologist Fabricio Garcez during his master\u2019s studies, and now in his current doctoral research at Eizirik\u2019s laboratory at PUC-RS. Some animals that resemble L. vetulus<\/em> have the mitochondrial DNA of L. gymnocercus<\/em>, a mixture corroborated by markers in the nuclear genetic material that each animal receives from both the father and the mother. Garcez is now conducting genomic analyses, and his preliminary findings indicate that all the foxes sampled so far from S\u00e3o Paulo State combine genetic material from the two species. The results also suggest that at least some of these animals were not from the first crossbred generation, offering an indication that the hybrids in this case are at least partially fertile.<\/p>\n

\u201cWe\u2019re seeing that the DNA of L. gymnocercus<\/em> is invading the populations of L.<\/em> vetulus<\/em> more often than it is not,\u201d says the PUC professor. This hybridization is quite probably caused by the changes brought about by human occupation, which causes him some concern. \u201cWe don\u2019t yet know whether this process will cause profound genetic changes that could affect the existence of the species,\u201d says Eizirik, who presented these discoveries at a symposium on 20 years of conservation genetics in Brazil at the Brazilian-International Congress of Genetics sponsored by the Brazilian Society of Genetics, held in Caxambu, Minas Gerais, in September 2016.<\/p>\n

In the interest of expanding the research and deepening our understanding of the genetic development of these foxes, Eizirik maintains that the ideal step would be to form a network\u2014of both researchers and citizens not connected with academia\u2014that could gather and share information, photographs, and even samples of biological material taken from animals run over by vehicles (the most frequent donors of genetic material), as well as data obtained on field expeditions and animals held in captivity.<\/p>\n

Scientific article<\/em>
\nTCHAICKA, L. et al<\/em>. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae)<\/a>. Genetics and Molecular Biology<\/strong>. V. 39, No. 3, p. 442-51. July\/September 2016.<\/p>\n","protected":false},"excerpt":{"rendered":"Deforestation promotes encounters between different species of foxes","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","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":[206,209,237,266],"coauthors":[1601],"class_list":["post-235313","post","type-post","status-publish","format-standard","hentry","category-science","tag-biodiversity","tag-biology","tag-genetics","tag-zoology"],"acf":[],"_links":{"self":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/235313","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\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/comments?post=235313"}],"version-history":[{"count":0,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/235313\/revisions"}],"wp:attachment":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media?parent=235313"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/categories?post=235313"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/tags?post=235313"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/coauthors?post=235313"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}