Editing Wallace Line (section)

{{Short description|Line separating Asian and Australian fauna}}
{{For|the line in triangle geometry|Simson line}}

[[File:Map_of_Sunda_and_Sahul.svg|thumb|Wallace's Line delineates Australian and Southeast Asian fauna. The probable extent of land at the time of the [[Last Glacial Maximum]], when the sea level was more than {{cvt|110|m}} lower than today, is shown in grey. The deep water of the [[Lombok Strait]] between Bali and Lombok formed a water barrier even when lower sea levels linked the now-separated islands and landmasses on either side.]]

The '''Wallace Line''' or '''Wallace's Line''' is a faunal boundary line drawn in 1859 by the British naturalist [[Alfred Russel Wallace]] and named by the English biologist [[Thomas Henry Huxley]].

It separates the [[biogeographic realm]]s of [[Asia]] and '[[Wallacea]]', a transitional zone between Asia and [[Australia (continent)|Australia]] formerly also called the [[Malay Archipelago]] and the Indo-Australian Archipelago (Present day [[Indonesia]]). To the west of the line are found organisms related to Asiatic species; to the east, a mixture of species of Asian and Australian origins is present. Wallace noticed this clear division in both land mammals and birds during his travels through the [[East Indies]] in the 19th&nbsp;century.

The line runs through [[Indonesia]], such as [[Makassar Strait]] between [[Borneo]] and [[Sulawesi]] (Celebes), and through the [[Lombok Strait]] between [[Bali]] and [[Lombok]], where the distance is strikingly small, only about 35&nbsp;kilometers (22&nbsp;mi), but enough for a contrast in species present on each island. 

The complex biogeography of the Indo-Australian Archipelago is a result of its location at the merging point of four major tectonic plates and other semi-isolated microplates in combination with ancient sea levels. Those caused the isolation of different [[taxonomic groups]] on islands at present relatively close to each other. Wallace's Line is one of the many boundaries drawn by naturalists and biologists since the mid-1800s intended to delineate constraints on the distribution of the fauna and flora of the archipelago.<ref name="Ali-Heaney-2021">{{cite journal |last1=Ali |first1=Jason R. |last2=Heaney |first2=Lawrence R. |date=June 2021 |title=Wallace's line, Wallacea , and associated divides and areas: History of a tortuous tangle of ideas and labels |journal=Biological Reviews |volume=96 |issue=3 |pages=922–942 |doi=10.1111/brv.12683 |pmid=33502095 |s2cid=231764849 |issn=1464-7931 |url=https://onlinelibrary.wiley.com/doi/10.1111/brv.12683}}</ref>