Gazelle : The Palestinian Biological Bulletin (ISSN 0178 – 6288) . Number 111, March 2014, pp. 1-9. | страница 3

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Indian Ocean and Indonesia. Since there are only two species of coelacanth and
both are threatened, it is the most endangered order of animals in the world. The
West Indian Ocean coelacanth is a critically endangered species (Wikipedia).
Coelacanths belong to the subclass Actinistia, a group of lobed-finned fish
related to lungfish and certain extinct Devonian fish such as osteolepiforms,
porolepiforms, rhizodonts, and Panderichthys. Coelacanths were thought to have
gone extinct in the Late Cretaceous, but were rediscovered in 1938 off the coast of
South Africa. Traditionally, the coelacanth was considered a “living fossil” due
to its apparent lack of significant evolution over the past millions of years; and
the coelacanth was thought to have evolved into roughly its current form
approximately 400 million years ago. However, several recent studies have
shown that coelacanth body shapes are much more diverse than is generally
said. In addition, it was shown recently that studies concluding that a slow rate
of molecular evolution is linked to morphological conservatism in coelacanths
are biased on the prior hypothesis that these species are “living fossils”
(Wikipedia).

The Coelacanth (Latimeria chalumnae) Model at the Zoologisches Forschungsmuseum
Alexander Koenig in Bonn, Germany. Photo by: Prof. Dr. Norman Ali Bassam Khalafvon Jaffa. 06.01.2003. http://www.flickr.com/photos/50022881@N00/10313557373/
Many species of coelacanth have been found as fossils. They are not large - thirty
centimetres or so in length. Some specimens have been preserved in miraculous
Gazelle : The Palestinian Biological Bulletin – Number 111 – March 2014