Dinosaurs and other mysterious prehistoric beasts came to life Saturday as the Houston Museum of Natural Science opened its new world-class paleontology hall to the public in the fourth largest US city.

The length of a football field, the hall is one of the most dynamic paleo halls in the world, and boasts one of the top three dinosaur exhibits in the United States, the museum said.

Houston Mayor Annise Parker joined a ribbon-cutting ceremony for the opening of the hall, as hundreds of eager students and local visitors swarmed the hall for the palaeontological wonder.

About 500 pieces are on display at the hall, said David Temple, associate curator of paleontology at the museum.

The innovative hall is packed with prehistoric beasts, and doesn't have the same stagnant displays of ancient skeletons standing in a row that many visitors are accustomed to seeing.

Rather, the predators and prey in the new paleontology hall will be in action - chasing, eating and escaping as they struggle for life.

Visitors will see more than 60 new, major mounts, featuring more than 30 dinosaurs as well as large mammals - all "in action" poses.

There is the museum's skeleton of a real bone T. rex featuring the best preserved and most complete hands and feet of any T. rex ever found, as well as patches of original skin - the likes of which have never before been seen.

Touchable specimens, including real and fossilized dinosaur skin, allow people to pet a dinosaur

Also on display is a nesting site for a Quetzalcoatlus family, ancient pterosaurs with 30-foot wingspans, bigger than a modern jet fighter.

A 12-foot wide, reconstructed jaw of a Megalodon, a marine monster that was the largest shark that ever lived, is poised in the act of ambushing a swimming, extinct elephant.

With the opening of the dinosaur hall, "we hope a lot of kids will get excited about science, about nature, about chemistry, about art, about biology, about geology, about all different things," said Temple.