Everyone agreed the pink dolphins were a good way to end a trip. Fresh-water dolphins, porpoising lazily in muddy water at the junction of the Napo and Amazon Rivers in the rain forest of Peru.

Sitting in a boat watching this performance in October 1999 is a group of nineteen people with Montana connections. Ostensibly, we're engaged in serious business—we've come to the Amazon to attend a medicinal plant seminar. The leader of our group is Rustem Medora, longtime UM pharmacy professor, known for his work in medicinal plants. Others in our motley crew include UM drug information specialist Amy Gruel, several pharmacy students, some practicing pharmacists, a physician or two, some biologists, and a couple of miscellaneous characters like me.

Our journey began a week earlier in Iquitos, Peru, where we boarded passenger boats for a 50-mile trip downriver to our first camp, Explorama Lodge . . .

Thatch-roofed villages line the bank, but human settlements slowly thin out until eventually there are miles-long stretches of river with no visible human habitation. In places the river banks are unstable and portions of them collapse, carrying sizable trees into the river as we pass.

Arriving, we tie up at the foot of a steep dirt bank into which stair steps have been cut, then walk past a herd of water buffalo lazing in a pool. Camp consists of several thatch-roofed, stilt-legged, long structures, the largest of which are our sleeping quarters. Each room has two single beds with mosquito nets, pegs for hanging clothes, a little bureau, a bucket, a tin wash basin and a mirror. Eight-foot tall, white-painted board walls leave air free to circulate above. Windows at the back of the rooms open to the surrounding forest.

We are advised to look out the window openings to make sure no one is below before emptying dirty water from our wash basins, but somehow I always forget to do that. I remember to look right after I throw the water. Impeccable pit toilets and showers are a short walk away. At dusk, men come and light oil lamps in our rooms and along the walkways.

Despite the exotic locale and architecture, the place has a Montana bunkhouse ambience that makes me feel immediately at home. Our first meal, in a thatch-roofed mess hall under kerosene lanterns, gets a five-star rating from me. It's a hearty dinner of Amazon catfish, with fruits and vegetables I'd never heard of. It's wonderful and reminds me of Montana ranch food.

We are 36 hours out of Montana with no sleep other than airborne catnaps. I lie under my mosquito net, listening to life seething in the forest for perhaps three seconds before I'm out like a light. The next thing I know, a rooster is crowing far away. In the dimness of dawn I begin to hope that I'm still a kid on a ranch, and everything since merely a dream. But suddenly a horrid racket erupts right outside our door as a half dozen resident macaws cut loose a blast of invective.

After breakfast, we head downriver to the Amazon's confluence with the Napo River, then up that river to Napo Camp, which is much the same as Explorama Lodge.

We soon fall into a routine that has almost a boot-camp thoroughness in its scheduling. Except, of course, we don't have to participate if we don't want to. We all want to. Most mornings, we get up shortly after dawn and take off on some pre-breakfast outing, such as a boat trip along the river to look for birds. Then, back for breakfast. After breakfast, class instruction on various aspects of medicinal plants. Lunch, class again, and then dinner, followed by after-dinner activities.

One favorite after-dinner activity, next to drinking cold beer in the bar, is the "bug walk," in which a bunch of us with flashlights head into the forest with a guide to look for night creatures. They give us advice before we go out—"don't stand in the ants," for instance. Question: When we all stop in the pitch black to shine our lights on something, how does a person know if he's standing in the ants? Naturally, I stand in the ants. I feel them double-timing in military formation up my leg, and it looks as if I might have to do a lightning trouser drop right in front of a very nice lady, but I manage to head them off.

"Lucky it wasn't a bullet ant," says our guide. The bullet ant is a magnum-sized jungle warrior that packs a punch at both ends, first fastening itself to one's flesh with large, powerful pincers and then applying its stinger repeatedly, twisting around to aggravate the bite while stinging as many other places as it can reach. A bullet might be friendlier.

Another after-dinner activity is piranha fishing. The river seems alive with these famous fish, and we often see them kicking up a frenzy on the surface. Despite the way they ate Charlton Heston's horse from under him in the movie, piranhas are said not to attack anything that is not injured and bleeding. Some members of our party cool off routinely by swimming in the river and not one of them is skeletonized.

On the other hand, if you take a bloody piece of water buffalo meat and lower it into the same water on a hook and line, you feel a vibration like electric current as swarming piranhas saw away at the tough meat. If the biting slows down, the canny piranha angler whips the water surface with his Amazon equivalent of a willow pole and the piranhas get excited and renew their attack on the buffalo meat. We adults can't fish effectively without our neoprene waders and our graphite fly rods, but some kids who came with their parents are less spoiled and they catch several and have them for dinner. Man bites piranha.

The most powerful impression I have of the Amazon rain forest is the overwhelming numbers of species. "Biodiversity" is a tedious word but an amazing thing to see. In one hectare (2.2 acres) of forest near Explorama Lodge, a researcher identifies 300 species of trees—more than 250 of them represented by only one specimen. Compare that to your Montana lodgepole forest. For some reason, plants in the Amazon usually don't grow near other plants of the same species. Nobody knows why, though theories abound.

And why does the Amazon need so many similar species? Nobody knows how many species of katydids live here, for example, but our bug walks demonstrate that there are worlds, maybe whole galaxies of katydids. Same with birds, lizards, monkeys, fish; almost any type of organism that lives here is represented by many species. On the river after dinner, strange southern stars emerge, the sky awhirl with Amazon bats, some only a couple of inches across, others seeming near the size of seagulls.

The Amazon also holds strange species that don't exist anywhere else and have no relatives. For example, the hoatzin (sounds like "watson") bird. This bird lives in the treetops over standing water and is about the size of a domestic chicken. It is not a picture of grace, flopping awkwardly around the treetops when approached. It is notable for having a two-chambered crop which it needs to digest leaves, somewhat in the way a cow digests grass. Young hoatzins have hooks on their wings, reminiscent of prehistoric creatures. When danger threatens, they bomb out of their nest and into the water below. When danger is past, hoatzins use their hooks to climb back up to the nest.

Napo Camp has one feature of particular interest to our herbal gang. This is a garden of medicinal plants kept by an authentic Peruvian Indian shaman, Don Antonio Montero Pisco. We tour his garden and he explains the uses of the plants. He hands around some innocuous looking flowers the diameter of a fingertip, which he says are used for toothache. I bite one of these, and in minutes a numbness sets into my jaw, not quite of Novocain thoroughness but no doubt very comforting if a tooth were rotting out.

The shaman has no shoes but wears a shirt with the words AllHerb.com, reminding us that it is a small enough world. AllHerb.com retains the shaman for his expertise. If you would like to ask the shaman a question, you can call up the Web page. The shaman is not online, however; a runner will carry your message to him out in the forest.

One recent question posed to the shaman: What have been the major changes to the Amazon in your lifetime? The answer: People are having too many kids. Forty years ago, he says, the forest came to the edge of the river everywhere. Now the forest is being cut back in many places to make way for expanding population.

After our stay at Napo Camp, we walk a half hour under the monkey-busy forest canopy to another camp, this one operated by the Amazonian Center for Environmental Education and Research (ACEER). This camp is much like the others, except that it doesn't actually have a bar. One must get one's beer or Fanta out of a refrigerator for oneself.

ACEER camp's main attraction is the nearby aerial walkway, stretching a quarter-mile long and as high as 113 feet through the forest canopy. The walkway is suspended on cables from large trees with platforms where visitors can stop and watch for birds.

One authority says the Amazon basin has 588 species of birds, compared to 700 for all the United States and Canada. In the few years the walkway has existed, 87 bird species have been observed from it.

Another feature at the ACEER camp is the useful plant trail. With a guide, we spend half a day on this trail in the forest, looking at the forty-five plant species valued by native Amazonians for medicinal or other uses, such as making blowguns or poison for use on blowgun darts. We are most interested in the medicinal uses. By this time we have learned a lot about medicinal plants in seminar sessions. Two of the best known authorities that talked to us were James Duke (See his herbal database at www.ars-grin.gov/duke.) and Varro Tyler, both of whom have written authoritative books on medicinal plants.

Our instructors recall for us the long history of plant-derived pharmaceuticals, going back at least to the isolation of quinine from Amazonian cinchona bark almost 200 years ago, the synthesis of aspirin based on an herbal remedy (willow bark) more than 100 years ago, to Taxol, derived from the Pacific yew bark and currently used as a potent anti-cancer agent. According to one authority, 231 of 520 drugs approved for use by the Federal Drug Administration or foreign equivalent between 1983 and 1994 were derived at least in part from natural sources. As of 1977, only 470 of an estimated 50,000 flowering plant species in the Brazilian Amazon had been thoroughly tested for chemical compounds that might be medically beneficial to humans.

While our brains are becoming massively informed about plants, our bodies gradually reset their clocks to a tropical lethargy. Toward the end of our week-long stay, I find myself sinking into a lazy euphoria; maybe in two more days I'll throw my shoes away and go native. Too soon it is time to boat back up the river, see the pink dolphins, and head for home.

Daniel Vichorek '69 writes on various Montana topics and lives in Helena.