Introduction | Inside Sulawesi | Animals of the Island | Resources
Introduction

The islands of the South Pacific teem with unique wildlife, and Sulawesi, an island in the Indonesian archipelago, is the most spectacular of all. Separated from other land masses by the Celebes, Flores, and Molucca Seas, Sulawesi is home to countless rainforests and an astonishing 11 active volcanoes. In this environment, as seen in NATURE, live some of the world's most unusual animals -- the CASTAWAYS OF SULAWESI, products of a geological accident.
Map of Sulawesi

Sulawesi is an island in Indonesia.
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The island's animals, first catalogued by naturalist Alfred Wallace in the 1850s, exhibit a rare mix of Asian and Australian traits. Some 70 million years ago, Australia and Asia were not separate continents, but a single land mass.
Sulawesi has 11 volcanoes

But Sulawesi's incredible wealth of indigenous wildlife is threatened by loss of habitat through farming, hunting, and most recently, the growth of the gold-mining industry. As you see in NATURE, miners refine gold using mercury, then indiscriminately dump the leftover chemicals into streams and rivers, tainting the water that both humans and animals use. As the mining shows no sign of ceasing, more and more living things are in danger of mercury poisoning.

As the region's tectonic plates shifted away from each other, Australia broke off to form its own continent and Sulawesi became an island. Left behind was a diverse gene pool that soon developed into populations of animals found nowhere else on earth. Isolated by the surrounding oceans, Sulawesi developed 18 species of lizards, 23 kinds of snakes, seven plants, 88 birds, and 79 mammals.

Nugget of gold

Gold mining is creating new health hazards.
A Voyage of Discovery

At the same time Charles Darwin was investigating life on the Galapagos Islands and other regions, his colleague Alfred Russel Wallace was island-hopping throughout Indonesia. Wallace noted remarkable differences between animals inhabiting the same islands: some showed Asian ancestry, some Australian.

Cuscus

The Australian cuscus . . .

By mapping a line between the islands of Borneo, Sulawesi, Bali and Lombok, Wallace highlighted a "biogeographic" region now called Wallacea, a biological transition zone for plants and animals. On one side of the line exist species that look Asian; on the other side, animals with Australian characteristics. Babirusa, tusked pigs of Asian descent, live alongside cuscus, pouched marsupials that probably developed from Australian genes. Both animals exist only on Sulawesi.

What was immediately apparent to Wallace was that an evolutionary process must have occurred to create these unusual species. Wallace recorded his thoughts in his 1869 book THE MALAY ARCHIPELAGO, concluding his own theory of evolution at the same time Darwin was developing his. So while Darwin gained fame as the originator of the evolutionary theory, Wallace became known as the father of biogeography, which looks at the patterns of distribution of animals and plants.
Babirusa

. . .  lives near the Asian babirusa.

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