Definition of Wallace's line
: a hypothetical boundary that separates the highly distinctive faunas of the Asian and Australian biogeographic regions and passes between the islands of Bali and Lombok in Indonesia, between Borneo and Sulawesi, and between the Philippines and the Moluccas
Origin of wallace's line
Alfred Russel Wallace
First Known Use: circa 1868
Learn More about wallace's line
Britannica.com: Encyclopedia article about "Wallace's line"
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