We’ve entered some profoundly unfamiliar planetary territory.

We’ve entered some profoundly unfamiliar planetary territory.

About 310 million years ago in what's now Arizona, a primitive creature trundled along on all fours through towering sand dunes that spilled into the sea. Normally, this creature's tracks would have vanished like other footfalls on a beach. But in a rare case, the tracks hardened into sandstone—preserving this flash of ancient behavior.

Some 310 million years ago, a reptile-like creature with an unusual gait roamed the sandy expanses of the Grand Canyon, leaving a trail of 28 footprints that can still be seen today. As Michael Greshko reports for National Geographic, these unusually well-preserved markers represent the national park’s oldest footfalls—and, if additional analysis links the early reptile to one that left a similar set of prints in Scotland roughly 299 million years ago, the tracks may even earn the distinction of being the oldest of their kind by more than 10 million years.

About 310 million years ago in what's now Arizona, a primitive creature trundled along on all fours through towering sand dunes that spilled into the sea. Normally, this creature's tracks would have vanished like other footfalls on a beach. But in a rare case, the tracks hardened into sandstone—preserving this flash of ancient behavior.

Speculation aside, there are valuable facts presented by the study, one of which is that we still have time to establish climate change policies to thwart catastrophic events, says UNLV geoscience professor and climate change expert Matthew Lachniet.

How could a civilization as advanced as that of the Mayas collapse in the space of a few hundred years? The key to this mystery that has been brewing historians for centuries may lie at the bottom of an ancestral lake in Mexico City, Science magazine reveals on Thursday, August 2 .

As one of the most advanced civilizations of its time, the Mayans left behind puzzles related to their extinction.

Mars, strewn with rocks and pocked by craters, may not have an Earth-like continental crust, according to a new study. Instead, researchers pose an alternative theory: Crystallized magma welled up from inside the red planet.

The sediment under a lake in Mexico contains some of the long-sought answers to the mystery of the Mayan demise.

In August 2012, the Mars Science Laboratory’s rover Curiosity landed at the base of Gale crater, a 5-kilometer-high mountain that formed when a meteor hit Mars billions of years ago. Using its 2-meter-long arm to drill into the planet’s surface, Curiosity scooped up and analyzed rock and soil samples, including some light-colored, crystal-studded rocks surprisingly similar to the ancient granitic rock that forms much of Earth’s continental crust.

In a lab at the Las Vegas Natural History Museum, researchers from UNLV are combing over fossils from a Columbian mammoth that was a real stand-up guy.