This tortoise is known from the associated remains
of a single individual consisting of nearly the entire
skeleton including the tail with its accompanying
armor (Meylan and Sterrer, 2000). It was regarded as
an endemic species in the extinct fossil genus
Hesperotestudo, which is otherwise known from the
Oligocene to Pleistocene of North America. Meylan
and Sterrer (2000) considered that the ancestors of H.
bermudae probably arrived by drifting or rafting from
southeastern North America. There are seemingly
only two possibilities that will account for the
presence of a specimen of fossil tortoise on Bermuda:
(1) A single individual of a species that has never yet
been found as a fossil on the mainland happened to
reach Bermuda, was fossilized, and then happened to
be discovered; or (2) There was once a viable population
of a tortoise on Bermuda of which only one individual
has yet been discovered. The first possibility is wildly
improbable but could be disproved by the discovery of
more fossils. If the second possibility pertains, can the
geological and extensive paleontological record of
Bermuda be reconciled with the fact no other tortoise
remains are yet known from the island? We believe that
this can be answered in the affirmative, although the
geological constraints on the time available for the
colonization, evolution, and extinction of H. bermudae
would accordingly be quite narrow.
This tortoise is known from the associated remainsof a single individual consisting of nearly the entireskeleton including the tail with its accompanyingarmor (Meylan and Sterrer, 2000). It was regarded asan endemic species in the extinct fossil genusHesperotestudo, which is otherwise known from theOligocene to Pleistocene of North America. Meylanand Sterrer (2000) considered that the ancestors of H.bermudae probably arrived by drifting or rafting fromsoutheastern North America. There are seeminglyonly two possibilities that will account for thepresence of a specimen of fossil tortoise on Bermuda:(1) A single individual of a species that has never yetbeen found as a fossil on the mainland happened toreach Bermuda, was fossilized, and then happened tobe discovered; or (2) There was once a viable populationof a tortoise on Bermuda of which only one individualhas yet been discovered. The first possibility is wildlyimprobable but could be disproved by the discovery ofmore fossils. If the second possibility pertains, can thegeological and extensive paleontological record ofBermuda be reconciled with the fact no other tortoiseremains are yet known from the island? We believe thatthis can be answered in the affirmative, although thegeological constraints on the time available for thecolonization, evolution, and extinction of H. bermudaewould accordingly be quite narrow.
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