published on Taylor and Francis <\/a>the scientists measured 183 fossilised anaconda backbones found in Falc\u00f3n State, Venezuela, South America, which corresponded to at least 32 snakes.Combining these measurements with fossil data from other locations in South America allowed them to figure out that ancient anacondas would have been four to five metres long. This is comparable to the current size of anacondas.What the study found\u201cOther species like giant crocodiles and giant turtles have gone extinct since the Miocene, probably due to cooling global temperatures and shrinking habitats, but the giant anacondas have survived – they’re super-resilient.\u201dSaid Andr\u00e9s Alfonso-Rojas, a PhD student and Gates Cambridge Scholar in the Department of Zoology at the University of Cambridge, lead author of the research.He added: \u201cBy measuring the fossils, we found that anacondas evolved a large body size shortly after they appeared in tropical South America around 12.4 million years ago, and their size hasn\u2019t changed since.\u201d<\/p>\nWhy are Anacondas still as big as they were 12 million years ago<\/p>\n
Why did the Anacondas grow so bigAs has been suggested for other large-bodied crocodiles and turtles, environmental factors like warm temperatures during the Middle Miocene Climatic Optimum and the existence of a vast wetland system in western Amazonia may have contributed to the evolution of a large body size in early Anacondas. However, unlike these other species, the global cooling that began during the Late Miocene and the shift to a transcontinental Amazon River system did not impact the body size of anacondas. Anacondas’ large size may have originated from a variety of prey species, low predator pressure, or competition with other predators; however, changes in trophic organisation from the earliest to Recent aquatic habitats in tropical South America are not associated with variations in body size.Why did Anacondas not go extinct or shrink in size Anacondas do well in swamps, marshes, and huge rivers like the Amazon. In the Miocene, the whole of northern South America resembled today\u2019s Amazonian region, and anacondas were far more widespread than they are now. But there is still enough of the correct environment, with the right food like capybaras and fish around, to allow current anacondas to keep being enormous.It was previously considered that anacondas must have been significantly bigger in the past when it was warmer, because snakes are extremely sensitive to temperature. Alfonso-Rojas said: \u201cThis is a surprising result because we expected to find that the ancient anacondas were seven or eight metres long. But we don\u2019t have any evidence of a larger snake from the Miocene when global temperatures were warmer.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"Anacondas are among the largest living snakes in the world. They are typically four to five meters long,…\n","protected":false},"author":2,"featured_media":171751,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[101533,101531,101530,101532,80696,85,46,141,101534],"class_list":{"0":"post-171750","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-anaconda-size","9":"tag-anacondas","10":"tag-ancient-anaconda-fossils","11":"tag-fossils-reveal-anacondas-were-giant","12":"tag-giant-snakes","13":"tag-il","14":"tag-israel","15":"tag-science","16":"tag-why-did-the-anacondas-grow-so-big"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/171750","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=171750"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/171750\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/171751"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=171750"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=171750"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=171750"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
![\"Fossils](\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2025\/12\/1765082240_687_fossils-show-anacondas-reached-colossal-size-far-earlier-than-thought.jpg\")
Anacondas are among the largest living snakes in the world. They are typically four to five meters long, though they can occasionally grow up to seven meters. A University of Cambridge-led research has rebuilt ancient anacondas from 12.4 million-year-old fossils uncovered in Venezuela, to determine these tropical snakes were a remarkable 5.2 metres long. Global changes have since driven many other enormous animals to extinction, although anacondas grow just as big today. Many animal species that existed 12.4 to 5.3 million years ago, in the period known as the \u2018Middle to Upper Miocene\u2019, were much bigger than their current kin due to warmer global temperatures, common wetlands and a surplus of food.While other Miocene giants – like the 12-metre caiman and the 3.2-metre large freshwater turtle have since gone extinct, anacondas broke the trend by living as a giant species as their ancestors. <\/p>\n