UNIQUE AND THREATENED BIODIVERSITY
The patchwork of isolated islands, the tropical location of the country, and the once extensive areas of rainforest have resulted in high species diversity in some groups of organisms and a very high level of endemism. There are five major and at least five minor centers of endemism, ranging in size from Luzon, the largest island (103,000 km²), which, for example, has at least 31 endemic species of mammals, to tiny Camiguin Island (265 km²) speck of land north of Mindanao, which has at least two species of endemic mammals. The Philippines has among the highest rates of discovery in the world with sixteen new species of mammals discovered in the last ten years. Because of this, the rate of endemism for the Philippines has risen and likely will continue to rise. Plants
At the very least, one-third of the more than 9,250 vascular plant species native to the Philippines are endemic. Plant endemism in the hotspot is mostly concentrated at the species level; there are no endemic plant families and 26 endemic genera. Gingers, begonias, gesneriads, orchids, pandans, palms, and dipterocarps are particularly high in endemic species. For example, there are more than 150 species of palms in the hotspot, and around two-thirds of these are found nowhere else in the world. Of the 1,000 species of orchids found in the Philippines, 70 percent are restricted to the hotspot. The broad lowland and hill rain forests of the Philippines, which are mostly gone today, were dominated by at least 45 species of dipterocarps. These massive trees were the primary canopy trees from sea level to 1,000 meters. Other important tree species here include giant figs ( Ficus spp.), which provide food for fruit bats, parrots, and monkeys, and Pterocarpus indicus, like the dipterocarps, is valued for its timber. Vertebrates
There are over 530 bird species found in the Philippines hotspot; about 185 of these are endemic (35 percent) and over 60 are threatened. BirdLife International has identified seven Endemic Bird Areas (EBAs) in this hotspot: Mindoro, Luzon, Negros and Panay, Cebu, Mindanao and the Eastern Visayas, the Sulu archipelago, and Palawan. Like other taxa, birds exhibit a strong pattern of regional endemism. Each EBA supports a selection of birds not found elsewhere in the hotspot. The hotspot also has a single endemic bird family, the Rhabdornithidae, represented by the Philippine creepers ( Rhabdornis spp.). In May 2004, a possibly new species of rail Gallirallus was observed on Calayan island in the Babuyan islands, northern Philippines. It is apparently most closely related to the Okinawa rail ( Gallirallus okinawae) from the Ryukyu islands, Japan. Perhaps the best-known bird species in the Philippines is the Philippine eagle ( Pithecophaga jefferyi, CR), the second-largest eagle in the world. The Philippine eagle breeds only in primary lowland rain forest. Habitat destruction has extirpated the eagle everywhere except on the islands of Luzon, Mindanao and Samar, where the only large tracts of lowland rain forest remain. Today, the total population is estimated at less than 700 individuals. Captive breeding programs have been largely unsuccessful; habitat protection is the eagle's only hope for survival. Among the hotspot’s other threatened endemic species are the Negros bleeding heart ( Gallicolumba keayi, CR), Visayan wrinkled hornbill ( Aceros waldeni, CR), Scarlet-collared flowerpecker ( Dicaeum retrocinctum, VU), Cebu flowerpecker ( Dicaeum quadricolor, CR), and Philippine cockatoo ( Cacatua haematuropygia, CR). Mammals
At least 165 mammal species are found in the Philippine hotspot, and over 100 of these are endemic (61 percent), one of the highest levels of mammal endemism in any hotspot. Endemism is high at the generic level as well, with 23 of 83 genera endemic to the hotspot. Rodent diversification in the Philippines is comparable with the radiation of honeycreepers in the Hawaiian...
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