{"id":136638,"date":"2025-11-13T00:48:07","date_gmt":"2025-11-13T00:48:07","guid":{"rendered":"https:\/\/www.newsbeep.com\/ie\/136638\/"},"modified":"2025-11-13T00:48:07","modified_gmt":"2025-11-13T00:48:07","slug":"55-million-year-old-crocodile-eggshells-found-in-australia","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ie\/136638\/","title":{"rendered":"55-Million-Year-Old Crocodile Eggshells Found in Australia"},"content":{"rendered":"

Named Wakkaoolithus godthelpi, this eggshell type belonged to mekosuchine crocodiles<\/a> and represent the oldest crocodilian eggshells ever found in Australia.<\/p>\n

\"Mekosuchine<\/a><\/p>\n

Mekosuchine crocodiles. Image credit: Armin Reindl \/ CC BY-SA 4.0.<\/p>\n

The now-extinct mekosuchines (Mekosuchinae) were Australia\u2019s own unique, local branch of the crocodile family.<\/p>\n

These creatures dominated inland waters of the continent 55 million years ago (Early Eocene epoch).<\/p>\n

They were part of the group of species that includes alligators, true crocodiles, gharials and caiman.<\/p>\n

But mekosuchines represent a much older branch than the saltwater and freshwater crocs found in Australia today.<\/p>\n

The modern species made their way to the continent much later, as it came into contact with southeast Asia about 5 million years ago.<\/p>\n

Unlike today\u2019s crocodiles, mekosuchines filled strange ecological niches.<\/p>\n

\u201cIt\u2019s a bizarre idea. But some of them appear to have been terrestrial hunters in the forests,\u201d said University of New South Wales Professor Michael Archer.<\/p>\n

\u201cThere are suggestions of this throughout a wide range of younger mekosuchine fossils that were discovered earlier within 25-million-year-old deposits from another region: the Riversleigh World Heritage Area, Boodjamulla National Park on Waanyi country in northwestern Queensland.\u201d<\/p>\n

\u201cSome riverine species there grew to at least 5 m long. Some were also apparently at least partly semi-arboreal \u2018drop crocs\u2019.\u201d<\/p>\n

\u201cThey were perhaps hunting like leopards \u2014 dropping out of trees on any unsuspecting thing they fancied for dinner.\u201d<\/p>\n

The Wakkaoolithus godthelpi eggshells belong to the oldest known member of the Mekosuchinae clade.<\/p>\n

\u201cThese eggshells have given us a glimpse of the intimate life history of mekosuchines,\u201d said Dr. Xavier Panad\u00e8s i Blas, a paleontologist with the El Museu de la Conca Dell\u00e0, the Institut Catal\u00e0 de Paleontologia Miquel Crusafont and the Universitat Aut\u00f2noma de Barcelona.<\/p>\n

\u201cWe can now investigate not only the strange anatomy of these crocs, but also how they reproduced and adapted to changing environments.\u201d<\/p>\n

The researchers examined the Wakkaoolithus godthelpi shell fragments under optical and electron microscopes.<\/p>\n

Their microstructure suggests the crocs laid eggs on the margins of a lake, with their reproductive strategy adapting to fluctuating conditions.<\/p>\n

\u201cMekosuchine crocs may have lost much of their inland territory because of encroaching dryland \u2014 eventually having to compete in the shrinking waterways not only with new arrivals to Australia, but dwindling numbers of their megafaunal-sized prey as well,\u201d said Dr. Michael Stein, a paleontologist at the University of New South Wales.<\/p>\n

\u201cThe Murgon lake was surrounded by a lush forest, which was also home<\/a> to the world\u2019s oldest-known songbirds, Australia\u2019s earliest frogs and snakes, a wide range of small mammals with South American links, as well as one of the world\u2019s oldest known bats.\u201d<\/p>\n

According to the team, fossil eggshells are an underused resource in vertebrate paleontology.<\/p>\n

\u201cThey preserve microstructural and geochemical signals that tell us not only what kinds of animals laid them, but also where they nested and how they bred,\u201d Dr. Panad\u00e8s i Blas said.<\/p>\n

\u201cOur study shows just how powerful these fragments can be.\u201d<\/p>\n

\u201cEggshells should be a routine, standard component of paleontological research \u2014 collected, curated and analyzed alongside bones and teeth.\u201d<\/p>\n

The findings<\/a> were published this week in the Journal of Vertebrate Paleontology.<\/p>\n

_____<\/p>\n

Xavier Panad\u00e8s I Blas et al. Australia\u2019s oldest crocodylian eggshell: insights into the reproductive paleoecology of mekosuchines. Journal of Vertebrate Paleontology, published online November 11, 2025; doi: 10.1080\/02724634.2025.2560010<\/p>\n","protected":false},"excerpt":{"rendered":"Named Wakkaoolithus godthelpi, this eggshell type belonged to mekosuchine crocodiles and represent the oldest crocodilian eggshells ever found…\n","protected":false},"author":2,"featured_media":136639,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[986,3690,79079,79080,79081,45185,78460,79082,9155,61,60,79083,82,79084,79085],"class_list":{"0":"post-136638","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-australia","9":"tag-crocodile","10":"tag-crocodilia","11":"tag-crocodilian","12":"tag-crocodylian","13":"tag-egg","14":"tag-eggshell","15":"tag-eocene","16":"tag-fossil","17":"tag-ie","18":"tag-ireland","19":"tag-mekosuchinae","20":"tag-science","21":"tag-wakkaoolithus","22":"tag-wakkaoolithus-godthelpi"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/136638","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=136638"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/136638\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/136639"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=136638"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=136638"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=136638"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}