Many of the 7107 islands that exist today were then linked together into bigger islands. These islands are called the ‘Greater Islands’ or ‘Ice-age Islands’ and represent the major Philippine faunal regions. Species could at that time freely distribute along those larger areas which later became separate islands. There are six major faunal regions in the Philippines:
1) Greater Luzon (Luzon Island with Catanduanes, the Pollilos and other small satelite islands)
2)Mindoro (which is surrounded by deep water and has only very few small islands around it that were connected to it then, such as Ilin Island)
3)West Visayas (Negros, Panay, Cebu, Guimaras, Masbate & Ticao)
4) Greater Mindanao (Mindanao mainland including Samar, Leyte, Bohol and smaller islands such as Basilan, Dinagat and Surigao)
5) Sulu Archipelago (Tawi-Tawi, Jolo etc.)
6) Greater Palawan (Palawan, Calamianes Islands, Balabac)
*****Reference and Further Reading*****
http://pbcfi.org.ph/news-2?fbclid=IwAR09dVMPy9_7sMxKh1z7CLE3CU6UmZB-xy2jVLxrTAA1xp9rg9h4CEsLfD0