A frog that incubated its eggs in its stomach might have held the key to treating stomach acid in humans. But sprawl and pollution wiped it out in the 1980s.

Amino acids found in the skin of other frogs might be able to block HIV. If the animals can be kept from extinction.

The man who is trying to keep that from happening is Charleston's own George Rabb, the legend you likely have never heard of. He also changed the concept of zoos. They aren't display pens anymore for animals that were trapped in the wild. They are active participants in conserving species and trying to keep them in the wild. His effort driving that transition was one among a career of conservation firsts.

Rabb, 81, is one of 29 people nominated this year for the 2012 Indianapolis Prize, a $100,000 award considered the world's pre-eminent honor for animal conservationists. The retired Chicago Zoological Society president is a signal figure in the field.

He is as ardently soft-spoken as his voice, so low key that a lot of people, even in the conservation community, aren't familiar with him, said Dana Beach of the Coastal Conservation League.

The award would be one more quiet achievement for a kid who spent hours in the 1940s in the old live amphibian and reptile room at the Charleston Museum, a kid who used to roam the salt marshes catching toads and snakes that he'd carry back to show people who were maybe not so thrilled.

"Oh, they tolerated it," Rabb recalls with a chuckle.

"It's George's turn. He deserves it. He's been more than a specialist. He put his career into saving as many animals as possible. He's the biggest picture guy you could ever imagine," said Joseph Mendelson, Atlanta Zoo herpetology curator, a long-time friend and the person who nominated Rabb. "If it hadn't been for George Rabb, this award wouldn't exist. His accomplishments are astounding."

'Insisted and persisted'

Rabb, 81, became research curator at the Brookfield Zoo in Chicago in 1959, at a time when animal behavior specialists like him went into academic research, not animal keeping, and zoos were actively buying for display animals plundered from their native habitats.

"At the time it was absolutely unheard of," Mendelson said.

Typically self-effacing, Rabb said he took the job because the people who hired him wanted to move more into research and conservation. And the zoo had a couple of elements that fascinated him. It had just opened a cutting-edge exhibit of wolves in a natural setting. And its staff kept stud books for the rare European bison and Pzewalski's horse on exhibit. That could be the key to conserving and breeding healthy captive species, Rabb realized.

"Without records you are handicapped in terms of understanding the relationships of individuals in a population," Rabb said. In the larger field of conservation, he was on new ground. Little if any research had been done on most zoo animals at the time. When Rabb began drawing blood from notoriously uncooperative rhesus monkeys, the keepers revolted, he said.

"You just insisted and persisted, and then tried to establish friendly relations," he said. He learned the way to get the message out: educating people on just how important diverse animals can be to human health breakthroughs.

Because of research by Rabb and others following his lead, zoos turned from collecting animals to breeding and exchanging their own, largely so they could prevent inbreeding. That helped cut down poaching. Zoos also began teaching the importance of protecting the biodiversity in the wild.

"He's been a force," said Shirley McGreal, founder of the International Primate Protection League, which is headquartered in Summerville. "The zoos traditionally had been bringing in animals from the wild. They bring in very little now. I think his influence spread."

'Connected the dots'

In 1989, Rabb took part in the first International Assembly of Herpetologists, in Canterbury, England. He became alarmed at what he heard, not in the presentations but in conversations in the "pubs and corridors." Researcher after researcher was telling him how species they worked with seemed to decline or disappear almost overnight -- in Australia, Central America, the United States.

Rabb realized the world might be looking at a mass extinction. He drove research that identified a deadly skin fungus literally being carried frog to frog as local species were transported around the world. Because of that work, a global effort is under way to find ways to diffuse the crisis and conserve healthy captive species as a fallback.

"George Rabb was the person who connected the dots," Mendelson said.

Rabb is the sort of old-era intellectual who, after an amphibian "shop talk" lunch with Mendelson, stops on his way out of a Chicago hotel, thrilled by a tapestry. He's someone who, while living in Brookfield, Ill., actively supports the Coastal Conservation League in his hometown and turns up in the East Bay Street offices every now and then to talk amphibians with Beach.

"He's a real gentleman, but he is as passionate about (conservation) advocacy as anyone I've ever met," Beach said.

"I'm a practical idealist, with some dreams of how we might better fit in and foster this place we inhabit," Rabb said. Despite the apparently escalating extinctions of species around the world, he remains stubbornly determined to protect the natural world.

"I'm optimistic we can mount the effort, but it's going to take a lot more recognition of what we're losing. We've got to wake up. The environmental simply isn't being attended to. We've got to wake up."

The six finalists for the prize will be selected in 2012, and the prize will be awarded in September.