... I quickly looked for information on ancestral species, and it appears that early coelacanths were not deep water fish. ...
Afaik\iirc all the (current) fossils that are at the 65+ million year end of the "gap" were found in shallow water environments (the issue of access to the fossil beds).
Living fossils like the Coelacanth
quote:
So, where do dry-land rocks come from? Well, some were formed on land, and some in fresh water, and some in shallow sea water. But very few were formed in deep sea water. Plate tectonics makes it clear why this should be. The deep ocean floor is constantly being destroyed, sucked down into the earth at subduction zones. It is unlikely for a piece of deep ocean floor to wind up as a dry-land rock.
For more information on their diversity and specific characteristics see:
Palaeos Vertebrates Sarcopterygii: OverviewPalaeos Vertebrates Sarcopterygii: Actinistia: HadronectorPalaeos Vertebrates Sarcopterygii : ActinistiaPalaeos: Very Incomplete Sitemap
(palaeos is (or was) a massive linked website on fossils and their divisions\cladograms, but is undergoing a major overhaul and so many links no longer work properly. You can search the site for specifics.)
But I came up blank on habitat of the fossils ... but with their diversity I would not be surprised that they used to inhabit a number of ecologically diverse depth environments.
Enjoy
Edited by RAZD, : clrty