“Every morning, the dinosaurs make such a racket, I can hear them outside my bedroom window, singing the dawn chorus. When I leave the house they are everywhere. I see them in parks, patrolling parking lots of shopping malls, on the prairie, along rivers, at the sea and in New York City where they live in astonish numbers. I often find them on my plate at fine and fast-food restaurants.”
– Jack Horner, paleontologist.

• • •

What comes after the chicken and its egg?

Native Montanan and world-famous paleontologist Jack Horner suggests an answer: After the chicken and its egg comes the return of the dinosaur.

Outside scientific circles, Horner is best known as the technical adviser for the movie “Jurassic Park” and its sequels. In the film, scientists cloned dinosaurs from DNA extracted from mosquitoes sealed in amber that formed more than 65 million years ago.

The idea was a slick piece of fiction but not a likely start for reviving T-Rex and company. Horner’s mind toyed with the idea and hatched a more likely scenario. Horner details his plot to retrieve dinosaurs from extinction in his latest book: “How to build a dinosaur.”

He would start with the only surviving line of dinosaurs, i.e. chickens. Chickens descended from small dinosaurs that walked on their hind legs and trailed long tails. At some point in its evolution, a gene stopped the tail’s growth. If the gene were switched on, the tail would grow again, Horner reasoned.

Horner calls it rewinding the tape of evolution.

“We can pick a species, study its growth, learn how it develops and learn how to change that development.”

Finding a mosquito engorged with dino blood and encased in amber would be like locating a pair of identical snowflakes. Chickens, on the other hand, are the most numerous birds on earth.

As such they are also the most populous tribe of dinosaurs that ever walked the earth.

The notion that birds are dinosaurs caught fire here in Montana. In 1964, Yale paleontologist John Ostrum found bones of a new dinosaur at a site near Bridger. Ostrum named it Deinonychus antirrhopus (literally “counterbalancing terrible claw).”

In 1969 he published a paper describing Deinonychus as fast, smart and hunting in packs with slashing claws. The beast had a metabolism that could support sustained effort. It was likely to have been warm-blooded, like birds or mammals, Ostrom argued. The paper helped start a revolution in the understanding of dinosaurs.

Horner was swept up in the revolution and contributed to it with his find of a nesting colony of duckbilled dinosaurs on the marge of an ancient sea.

Horner’s nests contained eggs and baby duckbills. The age of some of the babies indicated that (like birds) the parents tended their young. Juvenile bones gave evidence of rapid growth – too rapid for cold blooded animals.

• • •

News of dinosaurs as warm-blooded birds spread like prairie fire through the scientific community and glacially slow through the popular press. This past weekend an Associated Press article reported that an asteroid striking the earth exterminated the dinosaurs. It did not mention that one line of dinosaurs (birds) escaped the mass extinction.

A call this weekend caught Horner on his way to catch a plane. This year he will lead a busy season of 25 digs this year across the state while conferring with other scientists involved in the dinosaur revival project.

He notes in the introduction of “How to Build a Dinosaur”: “This is a project that will outrage some people as a sacrilegious attempt to interfere with life and be scoffed at by others as impossible, and by still others as more showmanship than science ... . When we get to the point of hatching a dinosaur it will be a decision that involves society as a whole, not a few scientists in a laboratory.”

• • •

“How to Build a Dinosaur,” by Jack Horner, Regents professor at Montana State University, and coauthor James Gorman, New York Times deputy science editor, Dutton, 246 pages, $32.50.