Exploring 7 of Earth’s Great Mountain Ranges

A hike along Australia’s Great Dividing Range would reveal a series of plateaus and low mountain ranges roughly paralleling the coasts of Queensland, New South Wales, and Victoria. The mountain range extends some 2,300 miles (3,700 km) from the Cape York Peninsula, Queensland, to the Grampians in Victoria Bass Strait between Australia and Tasmania. In Queensland, the mountains average is 2,000–3,000 feet (600–900 meters) in elevation, but they rise as high as 5,000 feet (1,500 meters) in the Bellenden Ker and McPherson ranges and the Lamington Plateau. Farther south, a segment known as the Australian Alps, near the New South Wales–Victoria border, contains Australia’s highest peak, Mount Kosciuszko (7,310 feet [2,228 meters]). Since the Great Dividing Range is not very high compared to other mountain ranges, few animals specifically adapted to mountainous environments occur there. Tree kangaroos and bird-wing butterflies occur in the rainforests of the mountainous northeast. Some bird species, such as the galah and the Australian magpie are found throughout Australia. Much of the Great Dividing Range is defined by forested areas of acacias, eucalyptus (see photo), and casuarinas, with hummock grasses and flowering plants, including banksias, in the undergrowth. The vegetation on the western slopes is predominately subtropical or temperate woodlands of eucalyptus and scrub. The Wollemi pine is a “living fossil” that was discovered in Wollemi National Park in 1994.

Although Ethiopia’s complex relief defies easy classification, of the five topographic regions in the country only two (the Western Highlands and the Eastern Highlands) might be classified as mountain ecosystems. The most spectacular portion is the North Central massifs in the Western Highlands; these form the roof of Ethiopia, the highest being Mount Ras Dejen at 14,872 feet (4,533 meters). Lake Tana (see photo)—Ethiopia’s largest inland lake and the main reservoir for the Blue Nile River—is located in this region, at an elevation of about 6,000 feet (1,800 meters). Another region, the Western Lowlands, are not what one would call low. They stretch north-south along the border with Sudan and South Sudan and include the lower valleys of the Blue Nile, Tekeze, and Baro rivers. With elevations of about 3,300 feet (1,000 meters), these “lowlands” are some of the hottest places on the planet.Several familiar African mammals live in Ethiopia, such as lions, leopards, elephants, giraffes, rhinoceroses, and wild buffalo, but these species rarely venture into the mountains. Uniquely Ethiopian mountain-dwelling species include the walia ibex of the Simien Mountains, the mountain nyala (a kind of antelope), the Simien jackal, and the gelada monkey. These creatures are endangered, and they appear in both the Western and Eastern highlands in numbers ranging from a few hundred for the walia ibex to a few thousand for the others.The primary vegetation types of the Ethiopian Highlands are moorland, grassland, and herb meadow. While much of the region is predominantly grass and heathland, a number of other plants are also characteristic. Punctuating the landscape is the lovely Rosa abyssinica, an endemic rose bush that towers up to 6.5 feet (2 meters) high. The kosso tree is used in traditional medicine as a vermifuge, and the wild African olive tree is found in many places throughout the range. One of the most unusual species is the giant lobelia, which reaches a height of 20 feet (6 meters) when flowering.

Travelers to the Andes wouldn’t find a single line of formidable peaks but rather a succession of parallel and transverse mountain ranges, or cordilleras, mixed with intervening plateaus and depressions. Found along the whole western edge of South America, they stretch from Tierra del Fuego in the south all the way to the continent’s northernmost coast on the Caribbean Sea, a distance of some 5,500 miles (8,900 kilometers). The Andes contain the highest peaks in the Western Hemisphere along with several volcanoes that make up the eastern margin of the Pacific “Ring of Fire.” The highest peak is Mount Aconcagua (22,831 feet [6,959 meters]) on the border of Argentina and Chile. All animal life is also affected by the abundance of food sources. For South American animals, the permanent snow line is the upper limit of habitation. Some plants and animals can live at any altitude, and others can live only at certain levels. Members of the cat family rarely live above 13,000 feet (4,000 meters), whereas white-tailed mice usually do not stay lower than 13,000 feet and can live up to 17,000 feet (5,000 meters). The camelids (llama, guanaco, alpaca, and vicuña) are animals primarily of the Altiplano—the high plateau of southeastern Peru and western Bolivia, which stands at 11,200 to 12,800 feet (3,400 to 3,900 meters) in altitude—although they can live well at lower altitudes. It is thought that the condor can fly up to 26,000 feet (8,000 meters). The Andes also hosts the guemul, puma, vizcacha, cuy (guinea pig), and chinchilla, among others.In the southern, Patagonian Andes, magnificent mid-latitude rain forests of the conifer genus Araucaria (see photo) and of oak, coigue (an evergreen used for thatching), chusquea, cypress, and larch are common. To the north, cloud forests can be found and are dominated by trees primarily in the families Lauraceae, Melastomataceae, and Rubiaceae. Throughout the Andes, the treeline gives way to grasslands, many of which are characteristically punctuated by a tall, thick-stemmed member of the aster family (Asteraceae), called Espeletia.

For thousands of years the Himalayas have held a profound significance for the peoples of South Asia, as their literature, mythologies, and religions reflect. Since ancient times the vast glaciated heights have attracted the attention of the pilgrim mountaineers of India, who coined the Sanskrit name Himalaya—from hima (“snow”) and alaya (“abode”)—for this great mountain system. In contemporary times the Himalayas have offered the greatest attraction and the greatest challenge to mountaineers throughout the world. The Himalayas have more than 110 peaks rising to elevations of 24,000 feet (7,300 meters) or more above sea level, including Kanchenjunga at the border of India (Sikkim state) and Nepal (see photo). One of these peaks is Mount Everest (Tibetan: Chomolungma; Chinese: Qomolangma Feng; Nepali: Sagarmatha), the world’s highest, with an elevation of 29,035 feet (8,850 meters).The fauna of the eastern Himalayas is similar to that of the southern Chinese and Southeast Asian region. The animal life of the western Himalayas, however, have more in common with the Mediterranean, Ethiopian, and Turkmenian regions. Elephants and rhinoceroses are restricted to parts of the forested Tarai region—moist or marshy areas, now largely drained—at the base of the low hills in southern Nepal. Asiatic black bears, clouded leopards, langurs (a long-tailed Asian monkey), and Himalayan goat antelopes (e.g., the tahr) are some of the denizens of the Himalayan forests. In the foothills one may find the Indian rhinoceros, musk deer, and the Kashmir stag (hangul), but in small numbers. In remote sections of the Himalayas, at higher elevations, snow leopards, brown bears, lesser pandas, and Tibetan yaks have limited populations. Above the tree line the most numerous animals, however, are diverse types of insects, spiders, and mites, which are the only animal forms that can live as high up as 20,700 feet (6,300 meters).The Himalayas are rich in floral biodiversity. On the western side of the range, the lower shrublands are defined by beautiful rhododendrons and meadows of grasses. In the eastern region, broadleaf forests receive almost 80 inches (200 centimeters) of annual rainfall and feature indigenous oaks and maples with orchids and ferns in the understory. As one ascends the mountains, the temperate sub-alpine conifer forests dominate the landscape with pine, hemlock, spruce, and fir. The Himalayan balsam and other small, flowering plants can be found above the treeline in the alpine regions.

The Atlas system is a series of mountain ranges in northwestern Africa that run generally southwest to northeast across Morocco, Algeria, and Tunisia. They extend for more than 1,200 miles (2,000 kilometers) from the Moroccan port of Agadir in the southwest to the Tunisian capital of Tunis in the northeast. Mount Toubkal at 13,665 feet (4,165 meters) is the highest point in the Atlas Mountains. Other imposing peaks in the Atlas include Mount Tidirhine at 8,058 feet (2,456 meters), the rugged bastion of the Ouarsenis Massif (which reaches a height of 6,512 feet[1,985 meters]), the Great Kabylie, which reaches 7,572 feet (2,308 meters) at the peak of Lalla Khedidja, and Mount Chelia (7,638 feet [2,328 meters]).Much of the land in the Atlas has been cleared for agriculture, and a small fraction of the forest cover remains. Animal life in the mountains is also in retreat. There remain only a few jackals, a few tribes of monkeys (Barbary macaques, the only African ape found north of the Sahara [see photo]) at higher elevations, and occasional herds of wild boars in the oak woods—found in the northern part of the range. With low rainfall and high rates of soil erosion, the Atlas Mountains are fairly sparsely vegetated. The areas with the highest rainfall feature moist forests of cork oaks with an undergrowth of arbutus (cane apple) and heather shrubs dotted with carpets of rockroses and lavender. Dry regions are populated with green oak and arborvitae (a species of pine tree) which form light, dry forests with a thin and bushy undergrowth. Stands of cedar dominate the higher altitudes, though the dry summits are often reduced to scattered stands of green oak and juniper trees.

Some 750 miles (1,200 kilometers) long and more than 125 miles (201 kilometers) wide at their broadest point between Garmisch-Partenkirchen, Germany, and Verona, Italy, the Alps are the most prominent physiographic region in Western Europe. Mont Blanc, at 15,771 feet (4,807 meters), is the highest peak in the Alps. Other tall peaks in the Alps include the Dufourspitze, Weisshorn, Finsteraarhorn, and the famous Matterhorn (see photo). All are at least 14,000 feet (4,300 meters) high. The ibex, a wild goat, and the goatlike chamois are extremely nimble in the craggy landscape. Marmots hibernate in underground galleries. The mountain hare and the ptarmigan, a grouse, take on white coats for winter. Several national parks in the Alps protect the native fauna. Although rising numbers of people in the Alpine regions has led to the disappearance of a number of species, some prized animals, including the European lynx, the brown bear, and the bearded vulture (lammergeier), have been successfully reintroduced. Deciduous forests of oak and beech give rise to mixed forests of beech and fir as the elevation increases. In the higher altitudes, dense evergreen forests of fir, larch, and pine dominate the landscape. In the alpine regions, one can find some of the most iconic flowers of the Alps, including edelweiss, alpine rose, heather, and gentian.

The Rocky Mountains are a massive cordillera made up of more than 100 separate mountain ranges stretching from Alberta and British Columbia to New Mexico. The spectacular vistas of the Rockies, such as St. Mary’s Lake in Montana’s Glacier National Park (see photo), have inspired countless mountain climbers, explorers, and even songwriters; John Denver wrote his famous anthem “Rocky Mountain High” about these uplands in 1972. Among the large mammals emblematic of the rugged backcountry are the black bear, grizzly bear, mountain lion, and wolverine. Bighorn sheep and mountain goats inhabit the high crags in summer and migrate to the lower slopes for the winter months. Members of the deer family, such as the caribou, elk (wapiti), mule deer, and white-tailed deer also migrate between alpine meadows and subalpine forests; the solitary moose lumbers across northern lakes, streams, and marshy areas, feeding on willow foliage and aquatic plants. Wolves, brought to near extinction by human predation, remain rare but have resurged since 1970 as their importance in the wilderness ecosystem has come to be appreciated. Smaller mammals of the lower elevations include the least chipmunk, red squirrel, Columbian ground squirrel, black-footed ferret, and marmot. Far below the tree line, one can walk amongst beautiful forests dominated by ponderosa pines and quaking aspen. Ascend a bit higher and the forests change to subalpine spruces and firs that get progressively more gnarled and stunted with the increase in elevation. Above the tree line, one will find alpine meadows of small, herbaceous plants that are hardier than their appearance would have you believe. These include blue columbine, snow buttercup, and pink phlox.