A new study shows that white sharks were once reduced to a single population in the southern Indo-Pacific Ocean. <\/p>\n
As the Earth warmed and ice melted about 10,000 years ago, sea levels rose. This allowed white sharks to expand again. Genetic divergence began around 7,000 years ago. That means these sharks eventually split into separate populations.<\/p>\n
\u201cThere are probably about 20,000 individuals globally,\u201d said<\/a> Gavin Naylor, director of the Florida Program for Shark Research. \u201cThere are more fruit flies in any given city than there are great white sharks<\/a> in the entire world.\u201d<\/p>\n Today, white sharks are found in three genetically distinct groups. One group lives in the Southern Hemisphere near Australia and South Africa. Another lives in the North Atlantic. The third lives in the North Pacific. These groups are widespread but still consist of relatively few individuals.<\/p>\n Scientists first noticed something odd in 2001. A study<\/a> found that while nuclear DNA from sharks<\/a> in different places was mostly the same, mitochondrial DNA differed sharply. Sharks in South Africa had distinct mitochondrial DNA from those in Australia and New Zealand.<\/p>\n This raised a question. Why would nuclear DNA be nearly identical, but mitochondrial DNA be so different?<\/p>\n","protected":false},"excerpt":{"rendered":"A new study shows that white sharks were once reduced to a single population in the southern Indo-Pacific…\n","protected":false},"author":2,"featured_media":50471,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[25],"tags":[49,48,316,66],"class_list":["post-50470","post","type-post","status-publish","format-standard","has-post-thumbnail","category-genetics","tag-ca","tag-canada","tag-genetics","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/50470","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=50470"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/50470\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/50471"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=50470"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=50470"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=50470"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}