{"id":221948,"date":"2026-03-26T20:16:09","date_gmt":"2026-03-26T20:16:09","guid":{"rendered":"https:\/\/www.newsbeep.com\/us-tx\/221948\/"},"modified":"2026-03-26T20:16:09","modified_gmt":"2026-03-26T20:16:09","slug":"giant-armadillo-mastodon-and-sloth-fossils-found-in-flooded-texas-cave","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us-tx\/221948\/","title":{"rendered":"Giant armadillo, mastodon, and sloth fossils found in flooded Texas cave"},"content":{"rendered":"

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The groundwater flowing through the subterranean cave systems of central Texas are vital for both farming and daily life. They\u2019re also underground, ancient archives of the past. In Comal County just north of San Antonio, Bender\u2019s Cave is yielding an unprecedented look at the megafauna<\/a> that once roamed the region around 100,000 years ago.<\/p>\n

Some of the animal bones lurking inside are completely unexpected, too. As University of Texas at Austin paleontologist John Moretti<\/a> and explorer John Young described in a paper recently published in the journal Quaternary Research<\/a>, central Texas was home to giant tortoises, ground sloths, mastodons<\/a>, as well as pampathere\u2014an ancestor of today\u2019s armadillo that grew as large as a lion.<\/p>\n

\"ManWith a wet suit and goggles, paleontologist John Moretti searched for fossils in the stream that flows through Bender\u2019s Cave. Credit: John Moretti<\/a> <\/p>\n

Unlike other paleontological<\/a> excavations, the team didn\u2019t need shovels or pickaxes. Instead, they swapped out their digging gear for snorkels and goggles. Formations like Bender\u2019s Cave are routinely filled with running streams that fluctuate in depth depending on recent rainfall, flooding, and sinkhole deposits. Erosion also frequently carries down animal bones from the surface, where they can remain undisturbed for thousands of years. Few caverns possess the same cache of fossils as Bender\u2019s Cave, however.<\/p>\n

\u201cThere were fossils everywhere, just everywhere, in a way that I haven\u2019t seen in any other cave,\u201d recalled Moretti. \u201cIt was just bones all over the floor.\u201d<\/p>\n

Moretti and Young visited the site six times between March 2023 and November 2024, ultimately surveying 21 separate zones. The fossils are now polished and rust-colored from mineralization after thousands of years underneath the water, but gathering samples was as easy as reaching down and grabbing them.<\/p>\n

Discoveries included a giant ground sloth\u2019s claw and ancient camel bones, but the pampathere was particularly striking. Originally from present-day South America, the massive armadillo ancestors eventually migrated into North America around 2.7 million years ago during the Pleistocene Epoch, and after the Isthmus of Panama was formed. An adult pampathere likely weighed as much as 440 pounds, but it didn\u2019t pose much of a threat to anyone. Unlike today\u2019s omnivorous armadillos, the pampathere\u2019s jaws and teeth were suited for coarse vegetation until they ultimately went extinct about 12,000 years ago.<\/p>\n

\"AA fossil claw from the giant ground sloth Megalonyx found in a Texas water cave. Scale bar is two centimeters. Credit: John Moretti \/ The University of Texas at Austin<\/a> <\/p>\n

A lack of comparative evidence means the fossils\u2019 ages aren\u2019t totally confirmed yet, but the study\u2019s authors believe they likely date back 100,000 years to the last interglacial period\u2014a comparatively warm era during the most recent ice age. If true, the bones are the first examples of interglacial animals discovered in central Texas.<\/p>\n

\u201cThis site is showing us something different, and that\u2019s really important because of all the work that\u2019s been done in this region,\u201d said Moretti. \u201cIf it is interglacial in age, it\u2019s a new window into the past and into a landscape, environment, and animal community that we haven\u2019t observed in this part of Texas before.\u201d<\/p>\n

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Andrew Paul is a staff writer for Popular Science.<\/p>\n","protected":false},"excerpt":{"rendered":"Get the Popular Science daily newsletter\ud83d\udca1 Breakthroughs, discoveries, and DIY tips sent six days a week. The groundwater…\n","protected":false},"author":2,"featured_media":221949,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[86382,223,86383,27,29,28],"class_list":["post-221948","post","type-post","status-publish","format-standard","has-post-thumbnail","category-texas","tag-fossils","tag-news","tag-paleontology","tag-texas","tag-texas-headlines","tag-texas-news"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/posts\/221948","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/comments?post=221948"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/posts\/221948\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/media\/221949"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/media?parent=221948"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/categories?post=221948"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-tx\/wp-json\/wp\/v2\/tags?post=221948"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}