Louis Antoine de Bougainville was born in Paris, France, in 1729. He joined the military and ended up in the French navy. He wrote an account of his voyages in the South Pacific called A Voyage Round the World, 1772. The French government paid Bougainville to circumnavigate, or circle Earth, in 1766. He could claim land for France. His party included scientists, including naturalists. His frigate ship was called La Boudeuse. It was 40 meters long and only 10 1/2 meters wide. Just over 200 men were on board.

Alexander von Humboldt was a German explorer and naturalist during the 1800s. His work contributed to the studies of  geography, climatology, ecology, and other sciences. Humboldt was fascinated with scientific exploration. Although German himself, he received permission from Spain to visit their colonies in Central and South America. These areas had been only accessible to Spanish officers and missionaries of the Roman Catholic Church. Humboldt was one of the first people to propose that the lands bordering the Atlantic Ocean were once joined (South America and Africa in particular).

English naturalist Charles Robert Darwin is likely the most famous of the ecological explorers. His voyage on the HMS Beagle, which began in 1831, helped him formulate his ideas about evolution. Darwin believed that animals and humans shared a common ancestry. He concluded that through natural selection, life evolved to the complexity we see today. His book On the Origin of the Species documented his theories. Interestingly, Darwin's knowledge of Humboldt's adventures in South America helped inspire his own voyage. His journals of his travels were also published as the Voyage of the Beagle.