Saturday, 6 July 2019

SAUROPTERYGIAN MANDIBLE

Libonectes atlasense / Andy Chua Collection
A beautifully preserved mandible of an Libonectes atlasense, an elasmosaurid plesiosaur from early Turonian, Upper Cretaceous,  deposits of the Akrabou Formation near Asfla Village, Goulmima, Errachidia Province in eastern central Morocco.

The collecting area is in the region of Drâa-Tafilalet. You may know Errachidia as Ksar Souk. It was renamed My Rachid, in honor of Moroccan royal family. Libonectes is an genus of sauropterygian reptile belonging to the plesiosaurs. Specimens have been found in the Britton Formation of Texas and the Akrabou Formation of Morocco. Sauropterygian reptiles were a diverse taxon of extinct aquatic reptiles that arose from terrestrial ancestors just after the Permian extinction event. They flourished during the Triassic then all but the Plesiosaurs became extinct at the end of the Triassic -- with Plesiosaurs dying out at the end of the Cretaceous.

Thursday, 4 July 2019

LAMPLIT DINOSAUR TRACKS

Ankylosaur Trackway / Tumbler Ridge
A detailed view of the Dinosaur Trackway near Wolverine River, Tumbler Ridge, northeastern British Columbia.

The tracks are filled with water to reflect the lamplight, making them both beautiful and easier to view.

There are three types of footprints found in the Tumbler Ridge GeoPark. At the Wolverine River Tracksite there are theropods (at least four different sizes) and ankylosaurs. Also found in the area are ornithopod tracks from herbivorous dinosaurs with their nice wide tracks. You'll recognize them by their short-wide prints with three blunt toes. There are rare wee hand prints associated with some of those tracks if you look closely.


Wednesday, 3 July 2019

ANKYLOSAUR TRACKWAY

Fossil Field Trip / Ankylosaur Trackway
After an exciting hike in the dark through the woods and down a steep incline, we reached the river. The tracks in this photo are from a type of armoured dinosaur that dates from around 97 million years ago in the Late Cretaceous.

Imagine a meandering armoured tank munching on ferns, shrubs and low-growing vegetation as the grasses we picture in fields today had yet to evolve en masse. Their time would come about 30 million years later. We've found grass-like phytoliths (related to modern rice and bamboo) in the poop (coprolites) from Cretaceous dinosaurs.

There are three types of footprints at the Wolverine River site, the meat-eating theropods (at least four different sizes), the slow, lumbering plant-eating ankylosaurs and duck-billed dinosaurs. Bones from an Acrocanthosaurus, a meat-eating theropod have also been found in the area. These bad boys lived in the Aptian, in the Early Cretaceous and known from a single species, A. atokensis.

The trackway you see here was made by one of those armoured lumbering ankylosaurs and a few of the prints carry skin impressions. Filling the prints with water and using lamplight was genius for viewing tracks as they are all but invisible in the bright sunlight by day.

Tuesday, 2 July 2019

FOOTSTEPS THROUGH TIME

Dinosaur Trackway / Trace Fossils
Walking along the beach at sunset, the last rays of the day catch the edges of ancient trackways of meat-eating dinosaurs who hunted in packs 100 million years ago. These were living, breathing, fear and awe-inspiring beasts that we may never meet in person but can imagine in vivid detail.

It is through their footsteps, these trace fossils, that we get our first peek at behavior we might not otherwise have known. Trace fossils or ichnofossils are burrows, footprints, tracks or even feces left behind by plants and animals that lived long ago. They may have scurried across a muddy exposure or eaten a tasty meal then pooped it out -- leaving behind clues to how they lived, what they ate and what the environment was like at the time.

Dinosaur footprints are an excellent example as they tend to make the news and are met with great excitement. Worm burrows on the other hand often go unnoticed and do not receive the hoopla and applause they deserve.

Ichnofossils can tell us a great deal about ancient environments, the behavior of ancient life and fill in gaps for us through the information they contain. As you might expect, trace fossils are often formed in soft substrates, particularly nice soft mud and sand. Those footprints you left at the beach or along a soft riverbank are candidates for fossilized trackways given the right condition and ichnological studies of the future.