Sahul

Sahul is the name of the continental Shelf of which the emerged parts are the Australia today, the Tasmanie and the New Guinea. The term, formerly used to indicate only the immersed parts, is used for from now on to indicate the emerged continental unit there is more than 10000 years (end of the last Glaciation), when the sea level was of more than 100m low, and that the majority of this plate was then emerged (Australia, Tasmanie and New Guinea joined together by terrestrial bridges), unintermitting only one formant named Sahul.

An original écozone

This plate is separated from the plate of the South-East Asia named Sunda by deep seas or straits. Those delimit an intermediate zone, the Wallacea, and especially the Ligne Wallace, practically insuperable line with the majority of the terrestrial animal species, which explains the deep differences between the two écozone S of each with dimensions of this line: écozone Indomalais E Sunda side, and écozone Australasian Sahul side. Sahul is identified with most of the écozone Australasien (which does not include also the Wallacea and the New Zealand), which includes/understands marsupial mammals like the Kangourou and the Koala, or of the monotrèmes like the Ornithorhynque, whereas the écozone Indomalais E includes/understands placental mammals .

Settlement by the man

Like it there forever have territorial continuity between Asia and New Guinea or Australia, this poses the problem of the colonization of the zone by the man. However excavate them archaeological attest of a human presence around 40.000 years BP in the North-West this continental unit, which implies that the man was to already use at the time them maritime boats in order to cross the Wallace line then the Mer of Timor from the islands indonésiennes.

However, the emergence of the majority of the grounds of the continental shelf between 40.000 and 10.000 years BP supported the propagation of the man on this new continent: the Sea of Arafura and the Strait of Torres between New Guinea and Australia being dry, those have acts like terrestrial truths bridges to make it possible the man to populate current Australia. Even thing enters Australia and the Tasmanie to the south, the Détroit of Bottom being him also dry lasting this period. Let us note that it is not improbable that these bridges in turn were opened or closed several times during the millenia.

Immersion of Sahul

Around 10.000 years BP begins the period of the Holocène characterized by a total warming and the cast iron of the Inlandsis. The sea level goes up gradually during the following millenia up to the current level. The seas and straits of the continental shelf are immersed little by little, letting exceed of Sahul only New Guinea, Australia and Tasmanie.

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