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THE WILSON JOURNAL OF ORNITHOLOGY • VoL 123, No. 3. September 2011 
BATANES ISLANDS 
Present-day dry land 
Ice-Age dry land 
GREATER 
PALAWAN 
Otus longiconus 
Otui mints 
Otus megalotts mugalou s 
Otus mega lolls rOgrorum 
Otus mega/otls evrreitr 
Mimaxiku gumtyt 
BABUYAN ISLANDS & 
Celebes MINDANAO 
Sea 
South 
China 
Sea 
subspecies uLd'in^is " ameS ° f maj ° r is,ands ’ and the distribution of scops owl species and 
represe'nTth^innmxhmt^t^t V*.*** rc P resenI contemporary configuration of the islands. Lieht grav areas 
,and ** WaS eXPOSed abOVC Sea leVCl durin « the P'eistocene glaciation cycles. 
35 mya as a group of small islands, southeast of 
the current location. Extensive volcanism during 
the last 15 million years shaped the coalescence of 
islands to form Greater Luzon. Greater Mindanao, 
including present-day Samar and Leyte, arose 
about the same time as Luzon. The Greater 
Negros-Panay block is believed to have emerged 
as one oceanic island ~2 mya and recently 
subdivided into the smaller islands including 
Panay and Negros (Heaney 1986, 1991: Hal! 
1996, 1998). 
One hypothesis to explain the complexity of 
community structure in tropical archipelagos is 
the elevational shifts of biomes during glacial 
