Starting Saturday, the California Academy of Sciences will be letting visitors take a walk on the prehistoric side with their new exhibit, “Dinosaurs: Ancient Fossils, New Discoveries.”

The exhibit, which is on the third leg of its national tour, is displaying many recent dinosaur-related discoveries.

Peter Roopnarine, curator of geology and paleontology for the academy, emphasized the importance of the dinosaur track fossils that are on exhibit.

“The sexiest fossils are the track fossils,” Roopnarine said. “Tracks let us know that dinosaurs underwent migrations, and they also can tell us about their speed.”

The exhibit features a 15-foot by 10-foot cast of the Davenport Ranch Trackway, a fossil of sauropod and theropod dinosaur tracks. Roopnarine explained that the trackway might show a possible hunting ritual along migration routes.

The largest display in the exhibit is a diorama of early crustaceous life featuring new findings from Liaoning Province in northeast China. This area has produced many useful fossils in the past decade due to the lack of disturbance in the surrounding area.

“Liaoning fossils are amazingly well preserved. Delicate features like skin texture and feathers are clearly visible,” said Andrew Ng, marketing and communications coordinator for the academy.

According to Ng, even the mighty Tyrannosaurus rex probably had feathers in its youth to keep it warm.

There is also a mechanical skeleton that simulates the movement of a T. rex, which is helping scientists assess its top speeds and muscular structure.

But dinosaurs aren’t the only ones in the spotlight in this exhibition.

Carol Tang, paleontologist and associate director of public programs for the academy, has spent the last few years focusing on prehistoric sea life.

“The academy has one of the best ammonite collections in the world,” said Tang.

Ammonites are extinct spiral-shaped sea life, and one of the more common fossils.

In addition to seeing actual fossils of sea life, visitors can watch one of the many videos explaining the significance of the artifacts they’re looking at.

Visitors also become part of the extinction gamble when they receive a “Passport through Time,” a card that assigns them one of 24 actual prehistoric species. At the end of the tour, visitors can find out if they or their descendents still exist.

The exhibit is open from 10 a.m. to 5 p.m. daily until Feb. 4, 2007 at 875 Howard St.

Admission is $6.50 for students, seniors and youth ages 12 through 17, $10 for adults and $2 for children ages 4 through 11.