Discover Indonesia’s most beloved island on this week-long itinerary, combining the cultural riches and lush countryside of Ubud with the calm seas and sandy beaches of Bali’s southeast coast.
The Wallace Line
Somewhere in the ocean depths amongst the islands of Indonesia runs an invisible line, separating the domain of tigers and hornbills from that of wallabies and cockatoos. This imaginary faunal line was the brainchild of eminent naturalist, Alfred Russel Wallace, whose travels through Indonesia gave rise to one of the most important biogeographical discoveries of our time.
British naturalist Alfred Russel Wallace was a contemporary of Charles Darwin, co-publishing the Theory of Evolution with Darwin in 1858. But his most famous field of expertise was evolutionary biogeography – the study of geographic distribution of plants and animals. Wallace travelled through the islands of Malaysia and Indonesia on his voyage in the 19th century, marvelling at the sheer diversity of flora and fauna of these spectacular archipelagos.
It was on these travels that Wallace noted how the islands in the western part of the archipelago (including Sumatra, Borneo, Java and Bali) were home to animal life similar to that found in continental Asia, whilst the easterly islands (including Lombok, Sulawesi and Timor) had species resembling those found in Australia.
Wallace’s theory was published in 1859, and whilst he could identify the different biogeographical zones, he couldn’t accurately explain why islands that were miles apart had similar species, whilst neighbouring islands had such vastly different fauna. Nowhere was this more baffling than in Bali and Lombok, two islands separated by the Lombok Strait, a 35 kilometre wide body of water. Wallace discovered that even species of birds and bats (who could happily fly the distance) did not cross this line.
This imaginary line became known as ‘the Wallace Line’, demarcating these two different ecozones. In the years since Wallace’s voyages through Indonesia and Malaysia, we have unearthed the existence of plate tectonics, which goes some way in explaining this natural phenomenon. However, Wallace’s discoveries and theories pre-date this relatively modern science by hundreds of years, making Wallace’s work way ahead of its time.
The Wallace Line continues to fascinate naturalists, zoologists and geologists to this day. Travel through the majestic Indonesian archipelago and discover the spectacular array of flora and fauna for yourself, from the elusive tigers of Sumatra and the elephants of Kalimantan, to the possums and tree kangaroos of Sulawesi.