PROBABLE CLAWS SAN DIEGO PUTS T. REX ON TRIAL - ONE OF MANY REIMAGININGS AT ITS NATURAL HISTORY MUSEUM.

Byline: Eric Noland Travel Editor

SAN DIEGO - THE TYRANNOSAUR, chomping away contentedly on triceratops tartar, perceived a threat to its feast. Without warning, it suddenly jerked its head forward and emitted a terrific roar.

The source of the threat, a girl of about 6, flinched noticeably and took a step backward. She hadn't been particularly hungry for fresh dinosaur kill anyway. Another little fellow watching this scene hopped on a bench and roared back at the beast.

The exhibit at the San Diego Natural History Museum breathes a bit of life into the customarily static display of skeletons and mock-ups at most such museums. This one features several scale-model animatronic dinosaurs, as the museum seeks to provide a sense of the sounds, sights and energy of the prehistoric world.

It's the premier attraction in a dramatically expanded exhibition space at the San Diego Natural History Museum, on the east side of Balboa Park.

The museum more than doubled in size when it opened a 90,000-square-foot wing in the spring of last year. The new space has a central atrium, with large windows on its north side and a skylight roof, all of which combine to create a sense of openness and to bathe some of the exhibits in natural light.

But such an environment wouldn't be appropriate for an exploration of upper North America millions of years ago. For that, visitors descend into the new wing's basement, where the distant roars of dinosaurs reach you from the darkness as you descend the stairs. (You might notice that really little visitors start grasping for Mom's hand at this point.)

The exhibit, which runs through early January, isn't all bells and whistles, though. Developed by the Museum of the Rockies, ``T. Rex on Trial'' is cleverly laid out as a courtroom case to determine whether the infamous tyrannosaur - a rampaging terror in everything from the ``Jurassic Park'' movies to video games - was a predator who chased down and overpowered its prey, as is commonly believed, or was a scavenger who freeloaded on other animals' kill.

Kids and adults who undertake this investigation find displays that provide information about different dinosaurs' bone structure, arm length, eyesight, sense of smell - all clues as to whether this one or that one was suitably equipped to stalk and chase.

It's a clever ruse: Your kids may think they're playing detective, but they're actually learning the basic tenets of the scientific method.

The robotics still steal the show, of course. There are nine animatronic dinosaurs. At one display, you can peer into a nest and observe wiggling, hatching dinosaur eggs as a mother allosaurus hovers protectively nearby.

At the conclusion of the exhibit, the dinosaur puzzles will be solved for you, with comprehensive analysis of evidence. It's amusing to learn that the first tyrannosaur fossil was discovered in 1905, and was referred to as a ``tyrant lizard king.'' The display is concluded with a complete cast of a tyrannosaur fossil skeleton, excavated in Montana in 1990.

The San Diego Natural History Museum also does a commendable job examining the interplay of land and ocean environments along the coasts of California and Baja California, and the new wing gives full vent to it.

One of the highlights of the current offerings is a giant-screen film, ``Ocean Oasis,'' which airs throughout the day in a 300-seat, amphitheater-style auditorium. The locally produced film, which won an award last year at the Jackson Hole Wildlife Film Festival, examines the contrast of life on the arid Baja peninsula and the lush waters just off its shore in the Sea of Cortez.

Watch two male elephant seals belly-bumping for dominance on a beach swarming with females, a moray eel snatching a scorpionfish in one terrific bite and two terns walking in such precise tandem that their movements are accompanied by tango music on the soundtrack.

After viewing this film, Mexico President Vicente Fox directed his environment secretary to complete the work necessary to raise the islands of the Sea of Cortez to bioreserve status.

Another exhibit, just off the atrium on the second floor, is vaguely titled ``Natural Treasures: Past and Present'' - which gives the museum an excuse to display everything from the bones of gray whales to mock-ups of saber-toothed cats to the skeleton of a giant mosasaur lizard. Here, you'll learn that the depletion of the California condor was owed in part to the fact that in modern times whale carcasses are removed from beaches as soon as they wash up on them, removing an important food source for the giant scavenging birds.

Also on this floor is ``Desert & Sea,'' an impressive collection of wildlife photos shot in Baja California.

Scheduled to open Sept. 28 in the first-floor Discovery Center is ``Animal Eyes,'' which will examine what scientists know about animal vision and how it differs from our own. It is to run through December.

SAN DIEGO NATURAL HISTORY MUSEUM

Where: Near the intersection of Park Boulevard and Village Place, Balboa Park. (Exit Interstate 5 at Pershing Drive; exit the 163 Freeway at Park Boulevard.)

Parking: The most convenient lots are just south of the museum, off Park Boulevard. Watch for the ``Museums'' sign.

Hours, costs: The museum is open daily from 9:30 a.m. to 5:30 p.m. After Labor Day, it will close at 4:30 p.m. daily. Current adult admission is $8, but that will drop to $7 after Labor Day. Senior admission (age 65 and up) is $6; children (ages 3 to 17) $5. The ``Ocean Oasis'' movie is included with admission.

Information: [phone]; www.sdnhm.org.

CAPTION(S):

3 photos

Photo:

(1 -- 2) The tyrannosaur exhibit, left, joins a newly constructed atrium, far left, at the San Diego Natural History Museum.

(3) A massive addition to the rear of the San Diego Natural History Museum in Balboa Park has dramatically increased the facility's exhibition space.

Eric Noland/Travel Editor