ThePhilippinearchipelago is one of the world's great reservoirs ofbiodiversity andendemism. The archipelago includes over 7000 islands, and a total land area of 300,780 km².

The Philippines was never connected to mainlandAsia vialand bridges,^{[dubious –discuss]} so the flora and fauna of the islands had to cross ocean straits to reach the Philippines. The Philippines is part of theIndomalayan realm, and its flora and fauna is mostly derived from tropical Asia.Botanically, the Philippines are part ofMalesia, afloristic province that includes theMalay Peninsula,Indonesia, andNew Guinea. Most of the Malesian flora is derived from tropical Asia, including thedipterocarps, which are the characteristic tree of the Philippine forests. Elements of theAntarctic flora, which originated in the ancientSouthern Hemisphere supercontinent ofGondwana, are also present, including ancient conifers likepodocarps (Podocarpus,Nageia,Sundacarpus) andaraucarias (Agathis).

Theecoregions of the Philippines are defined primarily by the sea levels during the Ice Ages, which were 120 meters lower than at present, as billions of gallons of water were locked away in huge continental ice sheets. This drop in sea level connected many presently separate islands into larger islands, which allowed for exchanges of flora and fauna:

• Greater Luzon includedLuzon,Catanduanes,Marinduque,Polillo, and several small islands.
• Greater Mindanao includedMindanao,Basilan,Bohol,Leyte,Samar, and adjacent small islands.
• Greater Palawan includedPalawan, Balabac, Busuanga, Culion, Cuyo, and adjacent small islands.
• Greater Negros–Panay includedNegros,Panay,Cebu, andMasbate.
• Greater Sulu included most of theSulu Archipelago, fromTawi Tawi toJolo.

These formerly-linked islands each constitute a separate ecoregion, as doesMindoro, which remained separate from the rest, along with a few smaller islands, notably Camiguin, Sibuyan, and Siquijor.

Each group of islands that were linked by land bridges in the ice ages also constitutes a separate faunal region. The lack of a land bridge to the Asian continent prevented most of the Asianmegafauna, includingelephants,rhinoceros,tapirs,tigers,leopards, andgibbons, from reaching the Philippines, although they do inhabit the adjacentIndonesian islands ofSundaland, which were formerly linked to the Asian continent by lowered sea levels.

The other main factor that defines the Philippine ecoregions is elevation; the highmountains of Luzon and Mindanao host distinct montane rain forest ecoregions. The mountains of Luzon are also home to theLuzon tropical pine forests.

by major habitat type^[1]
Tropical and subtropical moist broadleaf forests

• Greater Negros-Panay rain forests
• Luzon montane rain forests
• Luzon rain forests
• Mindanao montane rain forests
• Mindanao-Eastern Visayas rain forests
• Mindoro rain forests
• Palawan rain forests
• South China Sea Islands (disputed betweenChina,Malaysia,Philippines,Taiwan,Vietnam)
• Sulu Archipelago rain forests

Tropical and subtropical coniferous forests

• Luzon tropical pine forests

Source:^[2]

• Northern Philippine Islands
• Palawan – Busuanga – Mindoro
• Mindanao
• Lake Lanao

by marine province^[3]

• South China Sea
  • South China Sea Islands
• Coral Triangle
  • Western Coral Triangle
    • Palawan/North Borneo
    • Eastern Philippines
    • Sulawesi Sea/Makassar Strait

• Environmental issues in the Philippines

• Mammalian fauna of the Philippines (Field Museum of Natural History)
• Philippines biodiversity hotspot (Conservation International)

• Ecoregions of the Philippines
• Lists of ecoregions by country
• Philippines geography-related lists

• Articles with short description
• Short description is different from Wikidata
• Use mdy dates from May 2020
• All accuracy disputes
• Articles with disputed statements from July 2014