Sibutu Passage is a deep channel some wide that separates

Borneo Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...

from the

Sulu Archipelago The Sulu Archipelago ( Tausug: Kapū'-pūan sin Sūg Sulat Sūg: , ) is a chain of islands in the Pacific Ocean, in the southwestern Philippines. The archipelago forms the northern limit of the Celebes Sea and southern limit of the Sulu Se ...

. It has a deep sill allowing entry of deep water into the Sulu basin while connecting the

Sulu Sea The Sulu Sea (; Tausug: ''Dagat sin Sūg''; ; ) is a body of water in the southwestern area of the Philippines, separated from the South China Sea in the northwest by Palawan and from the Celebes Sea in the southeast by the Sulu Archipela ...

with the Sulawesi Sea that feeds from the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

by the Mindanao Current. Although H. Otley Beyer argued in favor of a settlement of the Philippines across

land bridge In biogeography, a land bridge is an isthmus or wider land connection between otherwise separate areas, over which animals and plants are able to cross and colonize new lands. A land bridge can be created by marine regression, in which sea le ...

s during the last ice age, modern bathymetric soundings have shown that the centers of the Sibutu Passage and the Mindoro Strait are both deep enough that they probably still existed at that time, although the Sulu and other

Philippine Islands The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

beyond were one connected island. If verified, therefore, the

Callao Man ''Homo luzonensis'', also known as Callao Man and locally called "Ubag" after a mythical caveman, is an extinct, possibly pygmy peoples, pygmy, species of archaic human from the Late Pleistocene of Luzon, the Philippines. Their remains, teeth a ...

would have needed to have crossed the open sea to reach the islands.

References

* ''Philippine Islands Sailing Directions'', third edition of the bulletin prepared in the office of the

United States Coast and Geodetic Survey The United States Coast and Geodetic Survey ( USC&GS; known as the Survey of the Coast from 1807 to 1836, and as the United States Coast Survey from 1836 until 1878) was the first scientific agency of the Federal government of the United State ...

Manila Manila, officially the City of Manila, is the Capital of the Philippines, capital and second-most populous city of the Philippines after Quezon City, with a population of 1,846,513 people in 2020. Located on the eastern shore of Manila Bay on ...

by Harry L. Ford, nautical expert (Washington, DC: Bureau of Printing, 1906), p. 171 * Lambert Anthony B. Meñez, Cesar L. Villanoy and Laura T. David. "Movement of Water Across Passages Connecting Philippine Inland Sea Basins" (Marine Science Institute, University of the Philippines, November 6, 2006) *

External links

Map of Sibutu Passage (channel), Philippines
Encarta - MSN
Malaysia Map - Malaysia Satellite Image
- Geology.com Straits of the Philippines Straits of Malaysia Malaysia–Philippines border International straits {{Philippines-geo-stub