Dinosaur Fossils Get New Life in School Museum : Painstaking Process Involved for Displays

When the discovery of some ancient dinosaur bones made headlines around the world last summer, the fossil diggers in Alaska and Arizona got all the glory.

Now the long and unglamorous process of preparing the fossils for study and display goes on at the University of California, Berkeley, Museum of Paleontology. The job calls for the instincts and tenacity of a detective, the bone-setting skills of an orthopedist and even some occasional dental work.

Dinosaur bones and models fill every corner of the basement room where fossil technicians Mark Goodwin and Kyoko Kishi and their student assistants work. From large dinosaur legs to tiny mouse teeth, each piece is carefully picked at, washed, glued, dried, catalogued and stored in one of the hundreds of metal cabinets on the Berkeley campus or displayed in museums around the country.

From Summer Digging

The tools of the trade are both esoteric and commonplace--a toothbrush here, a dentist’s drill there and, over in the corner, a $4,000 sandblasting device used to clean dirt and clay off the many fossils that come through the lab.

“We have millions of specimens,” said Goodwin, principal museum technician. “Students and professors generally go out each summer when most of the digging is done. Then everything is brought back here, where we prepare it.”

The museum at Berkeley has one of the largest fossil collections in the United States. Originally endowed in 1921 by C&H; Sugar Co. heiress Annie Alexander, an amateur naturalist, its activities center on management of its collections and a variety of public programs.

The most recent additions to the fossil collection are bones collected this summer from two news-making finds in Alaska and Arizona.

Professor William A. Clemens returned from the Alaska site with nearly 150 specimens that suggest that dinosaurs may have been able to survive a prolonged dark period that other scientists believe caused the extinction of the huge reptiles.

Fossil Named ‘Gertie’

From Arizona came contributions from paleontologist Robert Long, including remnants of a 225-million-year-old dinosaur skeleton discovered in the Petrified Forest. The fossil, named “Gertie” by the scientists, is believed to be the oldest dateable dinosaur skeleton, a 20-foot long phytosaur that might have weighed 15,000 pounds, Long said.

A fairly universal digging and plastering technique is used to remove fossil bones from any field site.

“In the field, we try not to take the material out piece by piece,” Long explained. Instead, a trench is dug around the skeletal outline and the top is covered like a mummy’s shroud with strips of burlap or medical bandages that have been soaked in plaster. When the cap has dried, the underside of the fossil is cut away from the rock, cleaned down to the bone and similarly bandaged.

Complete skeleton finds are rare, and more often one or two bones from a particular dinosaur are wrapped individually and shipped back to the laboratory.

Use Plastic Cement

“When they’re brought back here, the cocoons are opened on one side and the preparators infiltrate the bone with a hardening solution . . . usually a plastic household cement poured in as a liquid,” said Clemens, standing near a pile of plaster casts.

In the fall of each year, after the fossil diggers have come home from their summer explorations, the museum faculty and staff sit down to decide which specimens will be prepared. The reconstruction process normally takes six to eight months.

Hunched over the cast of a dome-headed dinosaur skull he is painting, Goodwin elaborates on the final stages of mold and cast making that he and fellow fossil technician Kyoko Kishi conduct.

The process involves painting layers of rubber latex film over the hardened fossil, forming a mold. The latex is then covered with a reinforcing outer jacket of plaster. A polyester or fiberglass resin is poured into the molds to make replicas of the original fossil. Occasionally the finished cast is painted to bring out details of the fossil.

Available for Research

In keeping with founder Alexander’s wishes, the finished specimens and casts are made available for research and public education at the Museum of Paleontology and for occasional traveling exhibits or loans to other universities.

Other materials, including Long’s collections from Arizona, will be returned to the museum at the Petrified Forest for display when the work is completed, about six months from now.

Meanwhile, Clemens recently presented the findings of his Alaska dig to the Geological Society of America, stirring the dust in a controversial debate on how dinosaurs disappeared from the earth.

His discovery of bones in an area that had a relatively cool climate, sparse vegetation and dark winters strengthens the view that dinosaurs hibernated and would have survived a similar blackout caused by an asteroid smashing into the earth 65 million years ago. Other scientists claim that the collision threw a gigantic cloud of dust into the air, blocking sunlight for an extended period and killing plants and animals--including the dinosaurs.

Sense of Humor

The theories on the demise of the dinosaurs are followed closely by those in the lab, but they are not without a sense of humor on the subject.

Ask them about their favorite theory, and they point to an office bulletin board. Tacked up there is a cartoon by “The Far Side” creator Gary Larson, showing a group of dinosaurs puffing away on cigarettes.

The caption: “The real reason dinosaurs became extinct.”