Fossilized animal tracks discovered in the Grand Canyon were likely left by a reptile some 313 million years ago, among the oldest found on Earth, a UNLV professor said.

In the American Southwest, native desert bighorn sheep populations found in landscapes with minimal human disturbance, including several national parks, are less likely to be vulnerable to climate change, according to a new study led by Oregon State University.

Finding fossil footprints at the Grand Canyon isn’t particularly unusual. The expansive stretch of red rock is home to an array of formations containing preserved remains of the past.

On Monday, former football great Herschel Walker rhapsodised about how Donald Trump had once accompanied his family to Disney World, while senator Tim Scott of South Carolina, the lone black Republican in the Senate, lauded Mr Trump for creating an “inclusive economy”.

Geologist Allan Krill was hiking along the Grand Canyon National Park’s Bright Angel Trail with a group of students in 2016 when he spotted it: a fallen boulder lying just off the side of the trail, with curious markings that resembled footprints. Krill, who was visiting the University of Nevada, Las Vegas (UNLV) from Norway, sent photos of his find to an old friend and colleague, Stephen Rowland, a UNLV paleontologist.

State Sen. Yvanna Cancela, Assemblywoman Selena Torres and several community members denounced President Donald Trump’s record with Latino communities during a conference call scheduled during the first day of the Republican convention in Charlotte, North Carolina.

Former football great Herschel Walker rhapsodized about how Donald Trump had once accompanied his family to Disney World. Sen. Tim Scott of South Carolina, the lone Black Republican in the Senate, took the stage to affirm the “goodness of America.”

A new research paper led by paleontologist Steve Rowland at the University of Nevada, Las Vegas analyzes this chance find of two sets of footprints (also called trackways) on the same rock that are potentially both from the same unknown species.

It's something like a modern-day chuckwalla, side-stepping sand dunes on an island in what now is Grand Canyon National Park.