{"id":653365,"date":"2026-05-06T13:25:15","date_gmt":"2026-05-06T13:25:15","guid":{"rendered":"https:\/\/www.newsbeep.com\/au\/653365\/"},"modified":"2026-05-06T13:25:15","modified_gmt":"2026-05-06T13:25:15","slug":"this-25-million-year-old-platypus-had-teeth-built-to-crack-open-armored-prey","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/au\/653365\/","title":{"rendered":"This 25 Million Year Old Platypus Had Teeth Built to Crack Open Armored Prey"},"content":{"rendered":"

\"\"<\/a>Artistic reconstruction of Obdurodon in its natural environment. Credit: Gen Conway\/Flinders University Paleontology Lab<\/p>\n

The platypus is already a bizarre mishmash of features, an egg-laying, duck-billed, venomous, and semi-aquatic mammal. But 25 million years ago, an even stranger prehistoric platypus swam through Australia\u2019s inland rivers, featuring teeth strong enough to crush shells.<\/p>\n

In a new paper, Flinders University paleontologists describe three rare fossils of Obdurodon insignis, one of the oldest known platypus species: two teeth and part of a shoulder bone from South Australia\u2019s outback. The finds show that ancient platypuses already swam much like modern ones, but also packed a bite their living relatives would later lose.<\/p>\n

A Desert That Was Once Water<\/p>\n

The fossils were pulled from Billeroo Creek, a patch of land east of the Flinders Ranges that is bone-dry today. During the late Oligocene<\/a>, some 25 million years ago, this was a lush world of permanent lakes and forested lowlands. It was a crowded neighborhood featuring lungfish, crocodilians, and even freshwater dolphins.<\/p>\n

For two decades, researchers have combed these ancient lakebeds, collecting over 1,000 vertebrate fossils. As erosion exposes new layers, the site keeps revealing pieces of a lost ecosystem. Yet, platypus bones remain the ultimate prize because they are so incredibly rare. <\/p>\n

The new haul is relatively small: a molar, a premolar, and a partial scapulocoracoid, a shoulder-girdle bone that supported the forelimb. Until now, Obdurodon insignis was known from only a handful of scraps, including teeth, a jaw fragment, and part of the pelvis.<\/p>\n

This \u201cnew\u201d haul is modest\u2014a lower molar, an upper premolar, and a piece of a shoulder. But the insights these few fossils carry is massive. Before this, O. insignis was basically a ghost, known only from a few dental scraps.<\/p>\n

\u201cPlatypuses are extremely rare in the fossil record and are often restricted to teeth, so it\u2019s exciting to find new material and learn more about these unique mammals,\u201d said study author Aaron Camens in the Flinders University statement.<\/p>\n

How to Recognize a Platypus<\/p>\n

Of course, the first question would be, how can researchers even know these small fossils are from a platypus?<\/p>\n

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They begin with the teeth. Mammal teeth preserve intricate patterns of cusps, ridges, roots and wear marks. Those details can act like a fossil fingerprint. The new lower molar from Billeroo Creek closely matches the original tooth used to describe Obdurodon insignis decades ago. It has the same broad chewing surface and multi-rooted structure, though it is larger.<\/p>\n

The premolar offers a second clue. Researchers compared it with teeth from Obdurodon dicksoni, a younger fossil platypus known from a much better skull. That skull gives scientists a clearer guide to what ancient platypus teeth looked like. The new premolar fits the same broad pattern, while differing enough from O. dicksoni to keep it with O. insignis.<\/p>\n

\"\"<\/a>Cast skull of Obdurodon dicksoni, American Museum of Natural History. Credit: Wikimedia Commons<\/p>\n

Moreover, the shoulder bone closely resembles the same part of the skeleton in a modern platypus, far more than in an echidna, the platypus\u2019s closest living relative. Its shape points to an animal that swam with powerful front limbs.<\/p>\n

The identification comes from several clues lining up: teeth that match known toothed platypuses, a shoulder built for swimming and fossils found in the freshwater world where such an animal belonged.<\/p>\n

Teeth Built for Tough Prey<\/p>\n

\"\"<\/a>Lingual view of the upper right second premolar and buccal view of the molar of O. insignis. Credit: Flinders University<\/p>\n

Then, once researchers confirmed that it\u2019s a platypus tooth, the goal becomes figuring out as much information from it as possible. <\/p>\n

Modern adult platypuses have no true teeth. They hatch with tiny vestigial teeth, lose them young and grind food with tough pads in their jaws.<\/p>\n

Obdurodon insignis was different. Its teeth were well formed, and the new premolar shows it had pointed front teeth as well as sturdy molars. That combination suggests a stronger bite and a diet that included hard-shelled prey.<\/p>\n

\u201cThe new material includes the first premolar, an important tooth in front of the molars,\u201d Camens said. \u201cThis shows Obdurodon insignis had large pointed front teeth which, with its large robust molar teeth, could easily have crushed animals with shells or exoskeletons like yabbies.\u201d<\/p>\n

Yabbies are freshwater crayfish. To an ancient platypus, they may have been ideal prey.<\/p>\n

The new lower molar is about 25% larger than the original tooth used to define the species, showing that O. insignis varied in size, much as another fossil platypus, O. dicksoni, did.<\/p>\n

\"\"<\/a>Study figure showing the fossil shoulder beside those of a modern platypus (Ornithorhynchus anatinus) and an echidna (Tachyglossus aculeatus). Credit: Flinders University<\/p>\n

The shoulder bone tells another story. When the researchers compared it with the shoulder of a living platypus, they found a close match. <\/p>\n

\u201cThis reveals a very similar forelimb structure to modern platypus, indicating it could swim just as well as its modern descendant,\u201d said Associate Professor Trevor Worthy in a statement. \u201cThese fossils show that 25 million years ago Obdurodon insignis was very similar to the modern platypus. It differed mainly by being slightly larger and having teeth.\u201d<\/p>\n

The Bite That Vanished<\/p>\n

\"\"<\/a>Ornithorhynchus anatinus. Credit: Wikimedia Commons<\/p>\n

Why did they give up the teeth? It\u2019s still an evolutionary mystery. It might have been a change in diet, switching from crunchy crayfish to soft insect larvae. Or, it might be the bill\u2019s fault. As the platypus\u2019s bill became a high-tech sensory organ for \u201cseeing\u201d electricity underwater, its mouth structure shifted, perhaps making teeth an evolutionary luxury it could no longer afford.<\/p>\n

Hopefully, new fossils will help scientists crack the case. For now, this just makes the platypus even harder to understand.<\/p>\n

In a desert that was once a watery world, paleontologists have found traces of an animal that feels both familiar and alien: a swimmer much like today\u2019s platypus, but armed with teeth powerful enough to crack open the hard shells of its prey.<\/p>\n","protected":false},"excerpt":{"rendered":"Artistic reconstruction of Obdurodon in its natural environment. Credit: Gen Conway\/Flinders University Paleontology Lab The platypus is already…\n","protected":false},"author":2,"featured_media":653366,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[298891,64,63,2931,25455,299607,116913,308220,55455,9867,96706,315925,128],"class_list":["post-653365","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-ancient-mammals","tag-au","tag-australia","tag-evolution","tag-fossil","tag-fossil-teeth","tag-monotremes","tag-obdurodon","tag-oligocene","tag-paleontology","tag-platypus","tag-prehistoric-platypus","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/653365","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=653365"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/653365\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/653366"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=653365"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=653365"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=653365"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}