Naturalist and explorer Alexander von Humboldt was born on September 14, 1769, in Berlin. His youthful interest in identifying and collecting natural objects – plants, shells and insects – developed into a passion for travel, inspired by a friendship with Captain James Cook’s illustrator who had sailed on Cook's second world voyage. During his scientific explorations of South America with a botanist, from 1799 to 1804, he collected 6,000 new species of plants, herbs, rocks, minerals and animals, and amassed a vast trove of maps and information about the natural world, ranging through geology, astronomy, meteorology, botany, anthropology and linguistics. On South America’s west coast, he discovered and measured what is now called the Humboldt Current in the Pacific Ocean. After exploring Mexico in 1803, he settled in Paris and later explored Russia. In 1845 he published the first of five volumes of “Cosmos,” a scientifically holistic treatise on the Earth and the universe. As famous as Napoleon in his time, von Humboldt promoted the interrelatedness of the natural sciences.