Wallace Line

The Wallace Line is a hypothetical line which separates the zoogeographical regions of Asia and Australasia. West of the line are found mostly species that are related to Asiatic species, to the east mostly species that are related to Australian species. The Wallace Line is named after Alfred Russel Wallace, who noticed the apparent boundary during his travels through the East Indies in the 19th Century. The line runs through the Malay Archipelago, between Borneo and the Celebes and between Bali (to the west) and Lombok (to the east) - the latter two separated today by a mere 35 kilometres. This was also noted in Antonio Pigafetta's journal during the voyage of Ferdinand Magellan in 1521, from the contrast between the Philippines and the Spice Islands.

Related Topics:
Zoogeographical regions - Asia - Australasia - Alfred Russel Wallace - East Indies - 19th Century - Malay Archipelago - Borneo - Celebes - Bali - Lombok - Ferdinand Magellan - 1521 - Philippines - Spice Islands

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One interesting note is that the distributions of many (but by no means all) bird species also observe the line, as many birds refuse to cross even the smallest stretches of open water. Arboreal placental mammals like bats and flying foxes have easily crossed the Wallace Line, but the terrestrial ones are limited to successfully rafting rats and shrews, and macaques: exceptions are the dwarfed endemic buffaloes and the babirusa of Celebes.

Related Topics:
Bird - Bat - Flying fox - Rat - Shrew - Macaque - Buffalo - Babirusa - Celebes

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