{"id":5538,"date":"2011-07-14T13:54:54","date_gmt":"2011-07-14T17:54:54","guid":{"rendered":"https:\/\/esa.org\/esablog\/?p=5538"},"modified":"2011-07-14T13:54:54","modified_gmt":"2011-07-14T17:54:54","slug":"scientists-dig-up-the-history-of-the-moles-extra-thumb","status":"publish","type":"post","link":"https:\/\/esa.org\/esablog\/2011\/07\/14\/scientists-dig-up-the-history-of-the-moles-extra-thumb\/","title":{"rendered":"Scientists dig up the history of the mole\u2019s extra \u2018thumb\u2019"},"content":{"rendered":"<p><a href=\"https:\/\/esa.org\/esablog-preprod\/wp-content\/uploads\/sites\/90\/2011\/07\/mole.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft size-full wp-image-5539 img-fluid\" title=\"Talpa europaea\" src=\"https:\/\/esa.org\/esablog-preprod\/wp-content\/uploads\/sites\/90\/2011\/07\/mole.jpg\" alt=\"\" width=\"551\" height=\"412\" srcset=\"https:\/\/esa.org\/esablog\/wp-content\/uploads\/sites\/90\/2011\/07\/mole.jpg 400w, https:\/\/esa.org\/esablog\/wp-content\/uploads\/sites\/90\/2011\/07\/mole-300x225.jpg 300w\" sizes=\"auto, (max-width: 551px) 100vw, 551px\" \/><\/a><\/p>\n<p>Marcelo S\u00e1nchez-Villagra from the University of Zurich and researchers have <a href=\"http:\/\/rsbl.royalsocietypublishing.org\/content\/early\/2011\/06\/29\/rsbl.2011.0494\">uncovered<\/a> the evolutionary history of the mole\u2019s extra \u201cthumb.\u201d As it turns out, this polydactyl animal evolved an elongated wrist bone to serve as a sort of extra finger, widening the paw for more effective tunneling.<\/p>\n<p>The researchers examined embryos of the Iberian mole (<em>Talpa occidentalis<\/em>) and the closely related\u2014but five-fingered\u2014North American least shrew (<em>Cryptotis parva<\/em>). They found that the \u201cthumb\u201d didn\u2019t begin to grow until the embryos were 18 days old, after the other fingers had already begun to develop.<\/p>\n<p>The digit, which does not bend but can wiggle, suggests a relationship with the testosterone level of these animals. According to a recent <em>Science Now <\/em><a href=\"http:\/\/news.sciencemag.org\/sciencenow\/2011\/07\/the-mole-loses-its-mysterious-se.html?etoc&amp;elq=3763f2c8228444cda13870f811456e26\">article<\/a>, \u201cTrue to their oddness, many female moles grow not only ovaries but also some testicular tissue, hinting that they have too much of the hormone, S\u00e1nchez says. Testosterone is well known for building bones, and some evidence suggests that human polydactyly\u2014people can occasionally develop genuine sixth fingers\u2014coincides with high levels of maternal testosterone.\u201d<\/p>\n<p>Read the original <a href=\"http:\/\/www.eurekalert.org\/pub_releases\/2011-07\/uoz-htm071411.php\">press release<\/a> \u201cHow the mole got its 12 fingers.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Marcelo S\u00e1nchez-Villagra from the University of Zurich and researchers have uncovered the evolutionary history of the mole\u2019s extra \u201cthumb.\u201d As it turns out, this polydactyl animal evolved an elongated wrist bone to serve as a sort of extra finger, widening the paw for more effective tunneling. The researchers examined embryos of the Iberian mole (Talpa occidentalis) and the closely related\u2014but&#8230;<\/p>\n","protected":false},"author":50,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[102,543,1234,1235],"class_list":["post-5538","post","type-post","status-publish","format-standard","hentry","category-research","tag-evolution","tag-genes","tag-mole","tag-polydactyl"],"_links":{"self":[{"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/posts\/5538","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/users\/50"}],"replies":[{"embeddable":true,"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/comments?post=5538"}],"version-history":[{"count":0,"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/posts\/5538\/revisions"}],"wp:attachment":[{"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/media?parent=5538"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/categories?post=5538"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/esa.org\/esablog\/wp-json\/wp\/v2\/tags?post=5538"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}