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Post by another specialist on Sept 4, 2008 6:45:39 GMT
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Post by Sebbe on Mar 12, 2017 16:21:01 GMT
Anyone able to find any sources confirming that a now extinct species once existed on Bermuda? my own searches only turns up information on Common Gallinule (Gallinula chloropus).
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Post by adzebill on Mar 12, 2017 17:11:43 GMT
See Olson, Wingate, Hearty & Grady "Prodromus of vertebrate paleontology and geochronology of Bermuda":
16. Fern Sink Cave.—-Also known as Grand Canyon
Cave (Hearty et al., 2004: fig. 5). Ca. 200 m NE of N 32°20’50.9” W64°42’46.0”. This cave system is entered
through a great fault cleft in the Walsingham limestone that extends to the water table. In the subterranean part, on the SW side there is an extensive, steeply inclined, deposit of red soil talus. Parts of this have experienced sheetwash that has created occasional erosional cavities in places. The deposits consist of a thin surface veneer of Holocene sediments and fossils, as evidenced by shells typical of modern-type Poecilozonites bermudensis along with bird bones, overlying a glacial soil as indicated by the presence of shells of P. nelsoni. Most of the bird bones from here appear to belong to an undescribed species of small gallinule (Gallinula). These fossils occur below a zone about 5 cm thick of sterile, apparently leached sediment.
The above-mentioned erosional cavities are in the glacial-age soil but may be lined with well-embedded
shells of P. bermudensis from the overlying Holocene.
Because of the sheetwash, the unconformity here is probably an erosional one that has removed the early
Holocene, although the deposits in Walsingham Sink Cave and the W wall red talus of Admirals Cave suggest
that the glacial/Holocene transition may have been a period of little deposition anyway. Charcoal from the
lower level containing gallinule bones gave a radiocarbon date of 20,080 ± 110 ybp (Beta 192239).
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