Level: Introductory

Reptiles (marine)

Many kinds of creature which lived in the past, have no living representatives now. We know about them from their fossils. These creatures were part of a rich variety of ecological communities that lived before the Flood of Noah. Living by the seashore, for example, there were far more kinds of sea shells than we find nowadays. Nevertheless, in their basic features, extinct creatures were not too different in body plan from modern examples. Thus extinct creatures had the same kind of body parts that we see in living species today.

Reptiles

We are familiar with several kinds of reptiles today. They all have a backbone and four legs (lizards, turtles and crocodiles) or no legs, like snakes. Their skin covering is scales, and they lay eggs which are protected with a shell. The reptiles of today are not super large (some crocodiles in Australia are the largest) and they all basically live on land and so are air breathing. There were reptiles in the past however that were extremely huge and that lived in the sea. These extinct creatures still had four limbs (which took the form of flippers). They were all air breathing of course so they could not stay under water indefinitely. Three impressive kinds of extinct sea dwelling reptiles are found in rocks of Alberta or nearby. These are ichthyosaurs, plesiosaurs and mosasaurs. You wouldn’t want to meet a living example of any of these creatures!

Ichthyosaur

The largest sea dwelling reptile ever found was near Pink Mountain, B.C. about 1998. This ichthyosaur was 21 m long (69 feet).  A predator, this creature hunted squid (fast moving relatives of octopus). Ichthyosaurs enjoyed the use of particularly well-designed eyes, no doubt useful for finding those squid. Compared to their body size, ichthyosaurs had the largest eyes of any animal. Larger eyes allow for better vision since they contain more light receptors to catch more rays. This specimen, displayed in the Royal Tyrrell Museum, features the bones attached as when it was alive. This means that as it was swimming along, it was suddenly and permanently overcome and buried by a horrendous amount of sediment which later turned to rock.

One of the most complete ichthyosaurs ever found was located in 2010 in Fort McMurray at the Syncrude Canada mine. This specimen was small however, only about 12 ft long (3.5 m). It is displayed in the Royal Tyrrell Museum in the posture in which it was found.

Plesiosaur

An almost complete skeleton of such an animal was found in 2007 at the Korite Mine in southern Alberta. Based on the number of individual bones in the back bone (76 heavy vertebrae), this creature had the longest neck of any known animal (with a backbone). Displayed in the Royal Tyrrell Museum, this specimen was 12 m long (39 ft) and of this, its neck was more than one half its total length. Good thing it lived in the water! Trying to keep such a long neck (more than 20 ft) from drooping along the ground, would be very difficult indeed. This animal also had heavy flippers. It was a huge heavy animal. Some very rapid water currents must have overtaken this creature and buried it in sediments that turned to rock. It takes a lot of energy (very fast churning water) to throw around such a heavy creature. It was flopped down in death like a rag doll. Another long-necked beauty was found in a competitor’s mine, Enchanted Designs in January of 2022. The Korite and Enchanted Designs mines exist south of Lethbridge, Alberta to dig up fossil shells of other sea dwelling creatures, extinct ammonites. Finding large extinct skeletons is not actually part of the business plans of these mines.

So, the ichthyosaurs looked something like fish, and the plesiosaurs exhibited extremely long necks with small heads. The most noticeable thing about mosasaurs was their large heads with massive jaws armed with many sharp teeth. Although mosasaur fossils have been found around the world, Alberta has recently been the scene of some impressive finds.

Mosasaur

In 2007 a well preserved mosasaur fossil was found in the Korite ammonite mine near Lethbridge, Alberta. Ammonites were extinct sea creatures that are something like octopus, but they were provided with a shell. The inside of these shells is very beautiful, reflecting light in amazing ways. These fossils can be turned into wonderful jewelry. Such fossils are found only in southern Alberta, nowhere else in the world. Two companies have charters to mine these fossils. However sometimes they also find fossils of scary air breathing creatures with backbones. Among such large creatures occasionally discovered in the Korite mine was a mosasaur in 2007. It was the first of its kind found with an intact skeleton.

Another very complete skeleton of a mosasaur was found at the same mine in 2012. It was a fully grown specimen 6.7 m (22 ft) long, one of the most complete ever found. Another partial skeleton was found in the same mine in May 2022. Apparently in total the Korite mine has turned up about 12 specimens in 40 years. Some of them exhibit stomach contents which include fish, turtles and other mosasaurs. These were fierce predators. In addition, in February 2022 Enchanted Mine discovered the largest relatively complete mosasaur. It was 20 ft long from its skull to the tip of its tail.

The thing to notice about these air breathing but sea dwelling fossils is how big they were and how fast they must have been permanently buried in order for them to be preserved until today. The preservation process was so fast that some specimens display undigested food in their guts. One specimen even had the last bone at the tip of the tail still connected. This tiny bone would have been lost very fast if there had been time for decay to begin soon after death. The catastrophes discussed here, involved animals in Alberta. Further study reveals however that such terrible events were worldwide in occurrence.