A severe drought has exposed 113 million-year-old dinosaur tracks on a river bed in central Texas.
Dinosaur tracks from around 113 million years ago, discovered after severe drought conditions dried up a river flowing through Dinosaur Valley State Park. Photo: AFP / Dinosaur Valley State Park
The massive tracks, which belonged to a single acrocanthosaurus, hadn't been seen since 2000, as they sat under water and several layers of sediment.
The tracks at Dinosaur Valley State Park in Texas are some of the best preserved in the world, said park superintendent Jeff Davis.
Almost all of Texas is facing drought according to the US Drought Monitor.
Last week, more than 87 percent of the state was experiencing one of the three most serious drought categories - severe, extreme and exceptional. The summer's excessively dry, hot conditions caused a river in the central Texas park to dry out almost entirely, revealing the tracks.
Superintendent Davis told the BBC that the recently exposed tracks are called the "Lone ranger trackway", belonging to one acrocanthosaurus, who walked that trail for about 100ft. There are an estimated 140 tracks in total from this one dinosaur, with about 60 visible now.
Dinosaur tracks from around 113 million years ago, discovered after severe drought conditions dried up a river flowing through Dinosaur Valley State Park. Photo: AFP / Dinosaur Valley State Park
Acrocanthosaurus, were therapods, a "typical three-toed dinosaur", Davis said. Standing at about 15 ft tall (4.57m), they would have weighed about seven tonnes.
These dinosaurs likely preyed upon the sauroposeidon. the other species whose tracks are also found in the state park.
The sauroposeidon stood at 60 ft (18.2m) tall with long necks and weighed about 44 tonnes as an adult.
Extreme weather has also led to other surprises.
Human remains have been discovered in Lake Mead - the largest US reservoir - as water levels decline. And in Europe, receding water levels have revealed "hunger stones" engraved at the waterline of rivers during previous droughts as a warning to future generations that when the stones are above water, suffering lies ahead.
Not all droughts are due to climate change, but excess heat in the atmosphere is drawing more moisture out of the earth and making droughts worse.
The world has already warmed by about 1.2C since the industrial era began and temperatures will keep rising unless governments around the world make steep cuts to emissions.
- BBC