A giant dinosaur tooth has been found in Alabama

An unusual find in an Alabama creek turned out to be the tooth of an ancient dinosaur that palaeontologists estimate could have reached 30 feet (about 9 metres) in length, Phys.org reported.

The shiny fossilised fragment was found by John Friel, director of the Alabama Museum of Natural History, during a field trip with a group of antiquities enthusiasts. The creek is about 80 kilometres southwest of Alabama State University in Tuscaloosa.

"I've been doing trips like this for ten years, but this is the first time I've come across a dinosaur tooth," Friel told reporters.

At first he mistook the find for a bone fragment, but then he noticed the characteristic enamelled surface and distinctive texture - it was clear that it was part of a tooth.

Already on site, two university palaeontologists confirmed that the find belonged to Hadrosaurus - a large herbivorous dinosaur with a "duck beak", which was capable of growing up to 30-50 feet (9-15 metres). Despite their size, these ancient lizards were quite fast and could probably outrun even Tyrannosaurus.

The most interesting thing is that hadrosaurs lived on land, while the discovery site was underwater during the age of dinosaurs. According to Friel, the creek is eroding sediments formed about 84 million years ago when the area was covered by the sea. It's common to find ancient shark teeth, ammonite shells and oysters here. But dinosaur teeth are a real rarity: Alabama has virtually no surface sediments of Jurassic age. All the local dinosaurs probably died on land, their remains washed out to sea, where they fell prey to marine predators and only then fossilised.

The found tooth is the base, a little more than a centimetre long, but for scientists such a find is very valuable. The exhibit has already been added to the scientific collection of the museum and will probably be included in an exhibition in the future.