A California family wasn’t ready to say goodbye after the death of their dog of 12 years, who had once saved them from a rattlesnake, so they had him cloned.

Ziggy is like a lot of other dogs, exuberant (精力充沛的) and curious, but he’s a clone of Marley, the first dog of his owners, David and Alicia Tschirhart.

“It’s gone beyond my expectations, as far as what Ziggy would be,” David Tschirhart said.

The Tschirharts had Marley for 12 years, and when he died, they weren’t ready to say goodbye. So the family turned to ViaGen, a company that offers cloning services for pets. It uses the same technology famously used to clone Dolly the sheep in 1997.

“They have the same personality. They play the same. They favor the same toys,” Alicia Tschirhart said.

The costs for ViaGen’s services are listed online with dogs at $50,000 and cats at $35,000. A spokesperson says they currently have a one-year waiting list.

But for the Tschuharts, it was a small price to pay to give new life to Marley, who the family says saved their lives in 2014.

When Alicia Tschirhart was about four months pregnant, the family was on a hike on Battle Mountain, and Alicia was looking for a walking stick. Marley sensed something his owners did not.

“I saw this really big stick, so I was focused on grabbing that, I didn’t even see the snake until Marley came and was clawing (用爪子抓),” Alicia Tschirhart said.

A rattlesnake had been right next to the stick, but it slithered (滑行) away when Marley jumped in to prevent disaster.

Five years after Marley’s death, the growing family has Ziggy-and, therefore, a piece of Marley-with them.

Above a shining ice pack in the Bering Sea, a helicopter flies over a polar bear, following paw prints in the snow. The bear suddenly appears as a hint of movement, white against white, making its way across the ice. The helicopter goes down, circling over the frightened creature, and a shotgun slides out the window, firing a tranquilizer (镇定剂) into the massive fur-covered bottom. Minutes pass. The bear shows no effects. The helicopter drops for a second shot. This time the bear stands its ground, and the pilot, fearing the animal is about to attack the aircraft, sharply noses the helicopter skyward.

But this bear finally moves unsteadily, then stretches out on the ice like a giant sheep dog. The helicopter sets down, and biologist Gerald Garner advances, kicking the bear in the behind to make sure it is motionless. A swivel (扭动) of its head and a flashing of teeth warn Garner that there is plenty of defiance left in this 272-kg meat-eating creature. With a syringe (注器), he injects more drug. At last the head lowers, and Garner can proceed. Around the bear’s neck he fastens a plastic collar containing a computer that will send data to a satellite, allowing scientists to keep track of the animal for a year. By the time Bear No. 6, 886 raises its head, the helicopter is softly above the air.

Those tense moments were all in a day’s work for Garner, one of a handful of hearty scientists, pilots and technicians taking part in a $700, 000 annual U. S. Fish and Wildlife Service study of polar bear populations. In an effort to follow the fate of more than 600 bears since the start of the program, the researchers have braved wind-chill factors of-59℃, hard living conditions, the constant threat of mechanical failures and the danger of being stuck on an ice pack. Last October two government biologists and a pilot disappeared while following polar bears from the air.

Three brown bears in the distance catches Charlie Russell’s eye. When they get a metre or so away from him, the huge animals slow down. The leading bear holds her face very close to Rusell’s. She touches his nose with her own and Russell breaks into a smile. “Hey, little bear,” he says.

Rusell, now 70, has spent more than ten springs and summers living with brown bears in the   eastern-most part of Russia.“No question, bears are dangerous,” says Russell, but he also argues that fearing them prevents us from recognizing their intelligent, playful and peaceful nature. “They attack us because we abuse them.” he insists.

“What I want to do now is work on the human side of the problem,” Russell says. In Canada —a country where cities spread deep into the rural landscape and hunters kill about 450 bears annually, he is determined to change the way we treat our neighbors.

Russell was raised with the idea that “the only good bear is a dead bear.” His father, a hunter, shared stories of cruel brown bears with his five children. However, when the family’s hunting business declined in the early 1960s, Russell joined his father on an expedition to film brown bears in Alaska. Russell couldn’t help but wonder why bears behaved aggressively towards people carrying guns, but left the film-makers alone. “I suspected they didn’t like cruelty,” he says.

In 1994 he tested out his theory in British Columbia’s Khutzeymateen Inlet, where he took tourists on bear-viewing tours. One afternoon, while resting on a log between guiding trips, Russell sat still as a female brown bear casually approached. “I knew if I did not move, she would keep coming,” he later said. “I had decided to let her come as close as she wanted.” Russell spoke to the bear in gentle tones and she sat down beside him. She put her paw on his hand and Russell responded to the gesture, touching her nose, lip and teeth. These were the iron jaws featured in his father’s campfire stories, now no more threatening than the nose of a little dog. If he could repeat similar moments, Russell believed he could prove that “just by treating bears kindly, people can live safely with them”.