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Explore Navassa - Biology |
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Navassa's last pseudopheonix |
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The biological diversity of the island and the fact that Navassa is U.S.
territory owe much to the geology of the island. The limestone island is
an uplifted atoll in the range of 5 million years old, giving rise to a
biota that has been isolated long enough have evolved independently of the
biota on surrounding land masses. 10-30m cliffs surround Navassa, making
it difficult for organisms to reach the island's high terraces.
Surrounding waters are 500 m deep, eliminating the possibility of land
connections to larger islands during Pleistocene sea-level lowstands.
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sea fans & coral |
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Fifteen island species are currently recognized as endemic and include land
snails, lizards, vascular plants, and possibly a ground dove. Two endemic
species, an iguana and curly tailed lizard found on the island during the
last century, could not be located and may be extinct. Common on the
island as late as 1928, only one specimen of the palm tree Pseudopheonix
sargentti saonae var. navassana remains.
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