Iguazú, Argentina (2007) — Along a subtropical jungle bordering Argentina and Brazil, Iguazú Falls contains a seemingly endless number of individual waterfalls, making it one of the world’s largest waterfall systems. (Photo by Dan Linehan)

Tierra del Fuego, Argentina (2007) — Old man’s beard (barba de viejo) grows in wispy, light green strands off a southern beech tree on a ranch. However, it doesn’t harm the tree. This lichen is very sensitive to pollution and thus a good indicator of air quality. Though the Spanish moss found hanging off trees in Monterey is similar in appearance to barba de viejo, Spanish moss is neither a lichen nor a moss but a flowering plant. (Photo by Dan Linehan)

Tierra del Fuego, Argentina (2007) — About 60 miles long and 3 miles wide, and shaped like a long, thin rectangle, Lake Fagnano forms a basin running between mountain ridges along the Andes Mountain Range. Underneath the lake runs the Magallanes-Fagnano Fault that separates two enormous tectonic plates, the South American Plate and the Scotia Plate. (Photo by Dan Linehan)

Tierra del Fuego, Argentina (2007) — An evergreen shrub within southern beech forests, calafate thrives in the subpolar, oceanic climate of Tierra del Fuego, which means Land of Fire. Once its branches are full of dark blue berries, getting by their long thorns to pick the berries is worth the occasional prick to a hand or a finger. (Photo by Dan Linehan)

Tierra del Fuego, Argentina (2007) — After being herded by sheepdogs, the sheep enter a corral that channels them into a single-file alleyway with a sorting gate at the end. The blue sheep get led off to have their wool coats sheared off, and the others are freed to return to roaming the ranch. (Photo by Dan Linehan)

Tierra del Fuego, Argentina (2007) — Three types of southern beeches make up most of the trees in Tierra del Fuego: tall deciduous (lenga), low deciduous (ñires), and coniferous (coihue). These are the leaves of a lenga, which has no noticeable fragrance when crushed between your fingers. (Photo by Dan Linehan)

Tierra del Fuego, Argentina (2006) — The size of golf balls, pan de indio, or Indian bread, is fungus that grows on southern beeches. It is edible raw and tastes like a bland mushroom with maybe a hint of garlic. (Photo by Dan Linehan)

Buenos Aires, Argentina (2011) — Yerba mate trees, a species of holly, grow at the botanical garden in Palermo. Yerba means herb, and the botanical name for yerba mate is Ilex paraguariensis. These are 1 of about 6,000 species of plants and trees from around the globe that grow across the garden’s 17 acres of lush, beautiful greenery. Not far from this patch, there is even a California coastal redwood. (Photo by Dan Linehan)

El Calafate, Argentina (2007) — Slightly larger than a California condor, the Andean condor has a wingspan that can exceed 10 feet. It can fly well over 100 miles a day in search of carrion. These three condors have landed in the foothills of the Andes Mountains to feed on a large animal carcass. (Photo by Dan Linehan)

El Calafate, Argentina (2007) — The Perito Moreno Glacier runs down from the mountains into Lago Argentino and divides the lake in two. The glacier’s tip touches land, and this contact point forms an ice dam between the two sides of the lake. Over time, each side fills, but at different rates. Eventually, when the ice dam breaks, water will rush from one side to the other until both levels are equal. The ice dam reforms, and the cycle repeats. (Photo by Dan Linehan)

El Calafate, Argentina (2007) — The force from so much ice cracking off the glacier and plunging into the water generates such an enormous splash that water and ice launch hundreds of feet in the air and strike the shore. This photo was taken at a distance of over 2,000 feet away. (Photo by Dan Linehan)

El Calafate, Argentina (2007) — The face of the Perito Moreno Glacier, in Patagonia, crumbles. (Photo by Dan Linehan)

El Calafate, Argentina (2007) — A sightseeing boat, about 60 feet long, must keep a safe distance from the Perito Moreno Glacier, which calves many times an hour. The blue patches on the glacier, which extend 180 feet above the surface, show where massive amounts of ice recently broke free. The falling ice becomes icebergs in water, which are then pushed away from the glacier by the giant, curved waves created by the impacts. As the waves die down to ripples, they still are big enough to rock the boat. After a few hours, the blue ice on the glacier’s face will turn white. (Photo by Dan Linehan)

El Calafate, Argentina (2007) — Though the Andes Mountains in southern Patagonia are Andean condor territory, the expanse and surrounding elevations make getting close to them quite difficult. After all, Torres del Paine and Fitz Roy are each less than a hundred miles away, which is nothing but a day trip for a high-soaring condor. (Photos by Dan Linehan)

Big Sur, California (2015) — Perched high on a mountain overlooking the Pacific Ocean, a California condor will soon take flight and make use of updrafts and thermals to carry it way into the sky. It can soar for hours and cover hundreds of miles during a flight. Condors are related to vultures but are considered to be as intelligent as primates. Condors eat carrion and have very acute senses that allow them to detect dead animals from miles away. Their main diet consists of land and marine mammals. Now, as well as in the past, eating animals contaminated with human-made toxins is the leading cause of condor death. Animal remains with lead bullet fragments continue to be the greatest threat to the recovery of the California condors, which now range as far east as the Grand Canyon in Arizona. Recent studies have revealed that a portion of the flock, living within range of the coast, is also being threatened by feeding on dead marine mammals that have bioaccumulated chemicals connected to the tremendous quantity of DDT that was dumped off the coast of California decades ago. (Photo by Dan Linehan)

Tierra del Fuego, Argentina (2007) — Distant relatives of camels, guanacos are one of four similar-looking species that include llamas, alpacas, and vicuñas. Grazers traveling in small herds, guanacos roam throughout Patagonia. Though one of the largest terrestrial mammals in South America, they still fall prey to natural predators, such as foxes and pumas. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — I took a picture of this caiman encircled by pesos, but I am not going to show it. There was an incident. As I photographed the caiman in the still water above Iguazú Falls, a bunch of knuckleheads started throwing pesos. I couldn’t believe it. I was outraged. I wanted to throw them in. But the caiman was too small to eat them and probably would have been scared off. That wouldn’t have done any good. So, I just yelled at them until they stopped and left. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — Water flows at more than 1,900 tons per second over Iguazú Falls, which is made up of 275 waterfalls ranging in height from 200 to 269 feet. To the far right of the Brazilian observation platform, Devil’s Throat waterfall sees the largest portion of this water cascading over its edge.

Iguazú, Argentina (2007) — No barrel is required. Spray from Iguazú Falls reaches 500 feet in the air. However, specialized boats bring people close enough to get drenched by falling water, to feel the roar soak through them, and to be stirred by the surrounding drumbeats of pounding water. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — There is hardly a better place to see butterflies than in a jungle next to waterfalls. Sulphurs (solid orange or solid green) and a swallowtail (black and yellow), as well as many other butterfly species fluttering around, stop for drinks in puddles of water. Some are bold enough to land on you and hitch a ride while they lick your skin. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — The Azara's agouti is a large, shy, and skittish rodent that can weigh over 10 pounds. It has a good reason to be on edge. Many of the jungle inhabitants, including ocelots and jaguars, prey upon them. Hunting by humans has also decimated their populations. These agoutis fulfill a very important ecological niche besides dinner for other animals. Known as “jungle gardeners,” agoutis are great at burying the nuts and seeds that they collect. Finding the them later is a different story. So, many plants grow from those left in the ground. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — A South American coatimundi pup eats a guava from a nearby tree. Related to raccoons, coatis are about the size of a large housecat. They often travel in packs and are comfortable enough around people to beg and scavenge for food. Guavas are good. Other food is not. For the health and welfare of these and other wild animals, heed the signs: “No alimente a los animales.” (Photo by Dan Linehan)

Iguazú, Argentina (2007) — An Argentine black and white tegu crawls along the edge of the tree line’s shadow. It can grow to 4.5 feet long, use its tail as a whip, and run short distances on two legs. A highly intelligent species of lizard, the tegu uses its tongue to collect scent particles, as do many other reptiles. An omnivore, it eats seeds, fruit, insects, and eggs. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — I tracked a toucan flying overhead to this tree. The silhouette of its bill, wings, and tail looked strangely symmetric, like a thick-stroked “+” sign. The sound of the toucan really surprised me, though. With a bill that big, I expected an equally big squawk, like from a large parrot. But the toucan just let out a small chirp every so often. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — Argentina and Brazil have national parks that encompass Iguazú Falls and the surrounding subtropical jungle, which contains around 2,000 species of vascular plants (trees, vines, flowers, shrubs, and the like). This false bird of paradise has draping flowers over a foot long with nectar that attracts many kinds of birds. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — Inquisitive, nosy, bold, opportunistic. These words describe this plush-crested jay. Is this jay just curious about me or is it waiting for the right moment to swoop down and snatch something to eat? Jays in South America are a lot like jays in North America. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — This banana tree joins many other types of fruit trees here in the jungle. Hundreds of species of birds, mammals, insects, and reptiles depend on this grocery store of nature. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — Rattling the tree canopy high above the jungle floor, black capuchin monkeys keep well hidden in the leaves and shadows. When they move quietly tree to tree, a way to locate them is by listening for a rain sound created when they move by wet leaves, spilling the collected water. (Photo by Dan Linehan)

Iguazú, Argentina (2007) — Me llamo Tarzan. Even if you don’t speak Spanish, does this really need a translation? In the subtropical jungle surrounding Iguazú Falls, traveling tree to tree by vine was much harder than it looks. But, I will add this: after falling on my ass, I learned that it was easier to swing from the thinner vine. (Photo courtesy of Dan Linehan)

Iguazú, Argentina (2007) — This is not a slug. It is a mob of caterpillars (species Perreyia flavipes) that are the larvae of sawflies and the relatives of bees, wasps, and ants. They’re doing something extraordinary. They are moving together in a synchronized blob called a rolling swarm. By crawling on top of each other, the entire mass can move more than twice as fast as any one individual caterpillar can move. It is very similar to how people walking on moving walkways at airports move faster than people who aren’t on them. Once caterpillars on the top level reach the front of the swarm, they drop down to the ground floor. When they reach the tail end, they climb back up and crawl to the front again. (Photo by Dan Linehan)

Deception Island, Antarctica (2007) — From inside the C-shaped volcanic caldera that forms the island, a wave can be seen breaking into an opening in the rocky coastline called Neptune’s Bellows. About halfway across Neptune’s Bellows, just below the surface of the water, is Ravn Rock, a long-known hazard for passing ships. (Photo by Dan Linehan)