Freshwater and Marine Plesiosaurs?
Plesiosaurs have been getting attention lately, and we have two complementary articles to examine. Those critters are a tricky bunch, and paleontologists get a mite confused. There is a prairie schooner-full of genera because...things change. Some were never official, others dropped because they are no longer considered plesiosaurs. Here is a list of 196 genera, at this writing.
Over yonder in Morocco on the border with Algeria is the Kem Kem region, with a geological group of the same name. Numerous dinosaur fossils have been found there. This is where plesiosaurs caused confusion.
Leptocleidus by Nobumichi Tamura at Wikimedia Commons (CC BY-SA 3.0) |
A recent study in the journal Cretaceous Research looked at the new plesiosaur finds in the Kem Kem Group in Morocco. The Kem Kem Group’s beds are primarily composed of sandstone and mudstone and are considered to be mid-Cretaceous to early Late Cretaceous. . . . The plesiosaur fossils found were determined to belong to the family Leptocleididae—a family of small, short-necked plesiosaurs often found in strata which have been interpreted as deposited in brackish or freshwater environments in other locales such as England, Africa, and Australia.
To read the full article, visit "Were Plesiosaurs Both Marine and Freshwater Animals?" Don't forget to come back for the next article!
Although plesiosaurs and ichthyosaurs are considered marine reptiles, there's no reason to get uppity and correct someone who calls them dinosaurs. They lived at the same time, were often found buried together, and are in postage stamp collections and toy collections together. Let it go, Layla.
Anyway, secularists were using the idea that some aquatic creatures are both marine and freshwater, so mayhaps these plesiosaurs left salt water and became freshwater. Or both, living in brackish water, since some kinds of marine fish breed in freshwater but spend the rest of their lives in a marine environment. Several speculations were made that have no evidentiary support.
Usually thought of as marine reptiles, plesiosaurs have been found on nearly every continent. Most are found within rock layers containing other marine organisms, but these were found in rocks with dinosaurs. . . .
Scientists . . . found bones of several small plesiosaurs scattered within the sandy beds of the Kem Kem Formation, a unit deposited as the Genesis Flood was nearing its peak. This same layer also contains spinosaur dinosaurs, frogs, crocodiles, turtles, and coelacanth fish, making for a rather odd collection.
You can read it all at "Claims of 'Freshwater' Plesiosaurs Drowned by the Flood." (I think the title means that the claims were drowned.) A short video segment follows that is supposed to start at 29:36: