Drought Uncovers Dinosaur Tracks in US Park

A handout image obtained on August 23, 2022 courtesy of the Dinosaur Valley State Park shows dinosaur tracks from around 113 million years ago. Handout Dinosaur Valley State Park/AFP
A handout image obtained on August 23, 2022 courtesy of the Dinosaur Valley State Park shows dinosaur tracks from around 113 million years ago. Handout Dinosaur Valley State Park/AFP
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Drought Uncovers Dinosaur Tracks in US Park

A handout image obtained on August 23, 2022 courtesy of the Dinosaur Valley State Park shows dinosaur tracks from around 113 million years ago. Handout Dinosaur Valley State Park/AFP
A handout image obtained on August 23, 2022 courtesy of the Dinosaur Valley State Park shows dinosaur tracks from around 113 million years ago. Handout Dinosaur Valley State Park/AFP

A drought in Texas dried up a river flowing through Dinosaur Valley State Park, exposing tracks from giant reptiles that lived some 113 million years ago, an official said Tuesday.

Photos posted on Facebook show three-toed footprints leading down a dry tree-lined riverbed in the southern US state. It is "one of the longest dinosaur trackways in the world," a caption accompanying the images says.

Stephanie Salinas Garcia of the Texas Parks and Wildlife Department said dry weather made the tracks visible.

"Due to the excessive drought conditions this past summer, the river dried up completely in most locations, allowing for more tracks to be uncovered here in the park," she said.

"Under normal river conditions, these newer tracks are under water and are commonly filled in with sediment, making them buried and not as visible," AFP quoted Garcia as saying.

Most of the recently revealed tracks were made by Acrocanthosaurus, which weighed nearly seven tons (6,350 kilograms) as an adult and stood 15 feet (4.5 meters) tall.

Another dinosaur, Sauroposeidon, also left tracks in the park. It measured 60 feet tall and weighed 44 tons in adulthood.

The state park -- located in an inland area southwest of the city of Dallas -- was once on the edge of an ancient ocean, and dinosaurs left footprints in the mud, its website says.

While drought revealed the tracks, rain is in the forecast, meaning they will likely be covered once more.

"While they will soon be buried again by the rain and the river, Dinosaur Valley State Park will continue to protect these 113 million-year-old tracks not only for present, but future generations," Garcia said.



This Ancient Tadpole Fossil Is the Oldest Ever Discovered

 A fossil of the world's oldest tadpole, which coexisted with dinosaurs in the Middle Jurassic about 165 million years ago, is pictured next to a 3D-printed representation of the tadpole and of a fully developed frog, in Buenos Aires, Argentina October 28, 2024. (Reuters)
A fossil of the world's oldest tadpole, which coexisted with dinosaurs in the Middle Jurassic about 165 million years ago, is pictured next to a 3D-printed representation of the tadpole and of a fully developed frog, in Buenos Aires, Argentina October 28, 2024. (Reuters)
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This Ancient Tadpole Fossil Is the Oldest Ever Discovered

 A fossil of the world's oldest tadpole, which coexisted with dinosaurs in the Middle Jurassic about 165 million years ago, is pictured next to a 3D-printed representation of the tadpole and of a fully developed frog, in Buenos Aires, Argentina October 28, 2024. (Reuters)
A fossil of the world's oldest tadpole, which coexisted with dinosaurs in the Middle Jurassic about 165 million years ago, is pictured next to a 3D-printed representation of the tadpole and of a fully developed frog, in Buenos Aires, Argentina October 28, 2024. (Reuters)

Scientists have discovered the oldest-known fossil of a giant tadpole that wriggled around over 160 million years ago.

The new fossil, found in Argentina, surpasses the previous ancient record holder by about 20 million years.

Imprinted in a slab of sandstone are parts of the tadpole's skull and backbone, along with impressions of its eyes and nerves.

“It's not only the oldest tadpole known, but also the most exquisitely preserved,” said study author Mariana Chuliver, a biologist at Buenos Aires’ Maimonides University.

Researchers know frogs were hopping around as far back as 217 million years ago. But exactly how and when they evolved to begin as tadpoles remains unclear.

This new discovery adds some clarity to that timeline. At about a half foot (16 centimeters) long, the tadpole is a younger version of an extinct giant frog.

“It's starting to help narrow the timeframe in which a frog becomes a frog,” said Ben Kligman, a paleontologist at the Smithsonian National Museum of Natural History who was not involved with the research.

The results were published Wednesday in the journal Nature.

The fossil is strikingly similar to the tadpoles of today — even containing remnants of a gill scaffold system that modern-day tadpoles use to sift food particles from water.

That means the amphibians' survival strategy has stayed tried and true for millions of years, helping them outlast several mass extinctions, Kligman said.