{"id":514603,"date":"2026-04-05T17:57:08","date_gmt":"2026-04-05T17:57:08","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/514603\/"},"modified":"2026-04-05T17:57:08","modified_gmt":"2026-04-05T17:57:08","slug":"they-went-snorkeling-in-a-cave-and-found-the-floor-covered-in-ancient-bones","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/514603\/","title":{"rendered":"They Went Snorkeling in a Cave and Found the Floor Covered in Ancient Bones"},"content":{"rendered":"

Paleontologists snorkeling through an underground stream in Central Texas have uncovered a rare collection of Ice Age megafauna, including a giant tortoise and a lion-sized armadillo relative whose presence in the region has no precedent in the scientific record. The findings, published in the journal Quaternary Research in March 2026, are prompting researchers to reconsider the ecological history of the Edwards Plateau.<\/p>\n

The discovery came after a local spelunker, John Young, photographed bones while snorkeling through Bender\u2019s Cave in Comal County and sent the images to paleontologist John Moretti<\/a> at the University of Texas at Austin. What began as an informal identification request turned into a multi-year field study, the first formal paleontological investigation of a water cave in Texas.<\/p>\n

An Unusual Assemblage Beneath the Surface<\/p>\n

Between March 2023 and November 2024, Moretti and Young made six visits to the site, collecting fossils from 21 sampling zones along an active underground stream. Many of the specimens were consistent with what scientists already knew about the region\u2019s Ice Age fauna: bones from saber-toothed cats, mastodons, mammoths, ground sloths, camels, bison, and horses were recovered from the shallow streambed.<\/p>\n

\"ResearchersResearchers navigate Bender\u2019s Cave\u2019s low-ceilinged stream passages and deeper pools during fossil collection. \u00a9 Quaternary Research<\/p>\n

But two finds stood apart entirely. Shell fragments and a scapula from a giant tortoise of the genus Hesperotestudo, and a single armor plate from Holmesina septentrionalis, a pampathere, an extinct relative of the armadillo that could reach the size of a lion, provided the first known records of either species on the Edwards Plateau. According to the published study<\/a>, no evidence of these animals had been found at any of the 17 other Late Pleistocene sites previously examined across the region.<\/p>\n

\u201cThere were fossils everywhere, just everywhere, in a way that I haven\u2019t seen in any other cave,\u201d Moretti said in a statement from the University of Texas at Austin. \u201cIt was just bones all over the floor.\u201d<\/p>\n

The physical condition of the fossils<\/a>, polished, darkly stained, heavily mineralized, and coated in calcite, points to prolonged exposure to the cave\u2019s carbonate-rich groundwater. The researchers believe the bones were swept into the cave through sinkholes during ancient flooding events and have since settled as a lag assemblage on the streambed floor.<\/p>\n

A Possible Window Into a Warmer Period<\/p>\n

The presence of the giant tortoise and the pampathere poses an interpretive challenge. The established paleoenvironmental record for the Edwards Plateau during the last glacial period, roughly 20,000 to 11,700 years ago, describes a cool, dry grassland. Neither animal would have been ecologically suited to that environment. Tortoises are restricted to warm climates, and Holmesina is associated with relatively warm, moist conditions in the broader North American fossil record.<\/p>\n

\"AA cluster analysis dendrogram grouping 43 Late Pleistocene Texas sites by megafauna similarity, with statistically significant clusters highlighted.\u00a9Quaternary Research<\/p>\n

The researchers attempted radiocarbon dating on two bone samples, but both lacked the collagen necessary for direct dating. An alternative method using bone mineral produced an age estimate of approximately 17,160 years, though the team notes that carbonate contamination in the cave environment makes this figure unreliable. According to the study, errors of this kind can skew results by as much as 20,000 years in either direction.<\/p>\n

A hierarchical cluster analysis comparing the Bender\u2019s Cave assemblage against 43 other Late Pleistocene sites in Texas placed the cave\u2019s fauna most closely alongside sites interpreted as dating to the last interglacial period, known as Marine Isotope Stage 5. That warmer interval, which preceded the Last Glacial Maximum and lies entirely beyond the reach of radiocarbon dating, would have supported the forest habitats and milder temperatures that species like the giant tortoise and the pampathere would have required.<\/p>\n

Moretti noted that the findings diverge from the established understanding of the region\u2019s prehistoric ecology, describing the cave as offering a view into a landscape and animal community that has not previously been documented in this part of Texas.<\/p>\n

David Ledesma<\/a>, an assistant professor at St. Edward\u2019s University who was not involved in the study, described the significance of the find in straightforward terms. Species previously thought absent from the region were present, and no existing framework fully explains why. The researchers are now focusing on uranium-thorium dating of cave mineral formations on the fossils, which could provide a more reliable minimum age for when the bones entered the cave system, and, by extension, when these animals may have lived in Central Texas.<\/p>\n","protected":false},"excerpt":{"rendered":"Paleontologists snorkeling through an underground stream in Central Texas have uncovered a rare collection of Ice Age megafauna,…\n","protected":false},"author":2,"featured_media":514604,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[59,90,56,54,55],"class_list":{"0":"post-514603","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-gb","9":"tag-science","10":"tag-uk","11":"tag-united-kingdom","12":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/514603","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=514603"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/514603\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/514604"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=514603"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=514603"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=514603"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}