Humboldt was generous in his support for young researchers and helped many at the start of their careers, but if he can be said to have had a favorite, that person was Franz Meyen (1804–40). When Humboldt first met him, Meyen was working as a physician. Humboldt secured for him the post of professor of […]

In 1924 the German botanist Adolf Engler (1844–1930) published Syllabus der Pflanzenfamilien (Summary of plant families). In this work, Engler set out his own system of plant taxonomy. Many herbaria, field guides, and floras still use Engler's classification, and the 12th edition of this two-volume work, edited by H. Melchior and E. Werdermann, was published […]

A HUMAN PERSPECTIVE During the Vietnam War, American troops were sent to fight in unfamiliar Southeast Asia. Among the hardships they endured was the tropical climate. Few had ever lived in a place that had a monsoon season with constant rain. One soldier wrote to his wife, “We live in mud and rain. I'm so […]

A HUMAN PERSPECTIVE Kublai Khan was the ruler of the Mongol Empire (which included China) in the 13th century. In 1281, the Great Khan sent a huge fleet against Japan. A typhoon—a tropical storm that occurs in the western Pacific—swept across the Sea of Japan and sank the Mongol ships or dashed them against the […]

A HUMAN PERSPECTIVE Every April and May, much of South Asia bakes in the heat. People endure temperatures that regularly top 100°F. Dust fills the air, and streams dry up. People walk for miles looking for water. Then—when it seems that no one can survive another day—the clouds roll in. The skies open up, and […]

A HUMAN PERSPECTIVE In the spring of 1999, three Canadian explorers retraced the steps of Sir Wilfred Thesiger's 1946 epic journey across the Rub al-Khali on the Arabian Peninsula. It is one of the most extreme deserts in the world. Like Sir Wilfred, they crossed using camels, not four-wheel drive vehicles. But unlike Sir Wilfred, […]

A HUMAN PERSPECTIVE In 1352, 48-year-old Ibn Battuta, a great traveler from Morocco, set out for the empire of Mali in West Africa. His most challenging obstacle was the Sahara, a desert nearly the same size as the continental United States. Battuta and his caravan set out in February. They traveled only in early morning […]

A HUMAN PERSPECTIVE Large areas of Russia and the Republics are extremely cold during much of the year. For example, the Siberian town of Oymyakon has reportedly had temperatures as low as –95°F. At such temperatures, the cold can crack steel and cause tires to explode. When you exhale, your breath freezes into crystals that […]

A HUMAN PERSPECTIVE Because of Greece's mild climate, the ancient Greeks spent much time outdoors. Greek men liked to talk with their friends in the marketplace. They also enjoyed sports. Large crowds gathered for athletic contests that were held during religious festivals. The most important of these was a footrace held every four years in […]

A HUMAN PERSPECTIVE In the 17th century, missionaries and Indians in the area of present-day Paraguay were at times attacked by jaguars, the great cats of Latin America. In 1637, packs of jaguars roamed the countryside, attacking humans. The Indians built barricades for protection from the savage cats. But the jaguars remained a source of […]

A HUMAN PERSPECTIVE A little gold and bitter cold—that is what thousands of prospectors found in Alaska and the Yukon Territory during the Klondike gold rushes of the 1890s. Most of these fortune hunters were unprepared for the harsh climate and inhospitable land of the far north. Winters were long and cold, the ground frozen. […]

A HUMAN PERSPECTIVE In the 1870s, a settler described prairie land in Tazewell County, Illinois, as having western meadow lilies “as high as a boy's head,” rippling waves of wildflowers, and grass so dense that a man on horseback 30 yards away could not be seen. At that time, the land produced crops of grains, […]

Over the last few thousand years, human societies have come to dominate much of the land area of our planet. We've changed the natural vegetation—sometimes drastically—of many regions. What exactly do we mean by natural vegetation? Natural vegetation is a plant cover that develops with little or no human interference. It is subject to natural forces, storms, or fires that […]

THE COMPOSITION OF associations among plant species tends to vary regularly across gradients of altitude, latitude, temperature, soil types, and other variables. Making use of this observation, biogeographers are able to delineate distinct sets of conditions along such gradients that reflect changes, sometimes abrupt, in the distribution of plant associations. Where two or more such changes occur, the ecology of a […]

GEOGRAPHERS ARE CONCERNED with studying elements of the natural and human environments. They want to determine the relationships between these elements and wish to explain their patterns of location. Vegetation is an important and highly visible element of the natural and cultural environment. To the trained eye, vegetation offers a rapid means of determining habitat suitability for various human endeavors. One way […]