CRETACEOUS SPINE LIZARD: SPINOSAURUS

Spinosaurus was a huge carnivorous theropod dinosaur who lived in the swamps of North Africa during the upper Albian to upper Turonian stages of the Cretaceous, some 112 to 93.5 million years ago.

Larger even than some Tyrannosaurus and Giganotosaurus, this fellow weighed up to 21,000 kg and with all that mass was still an accomplished swimmer.

The genus was known first from Egyptian remains discovered in 1912 and described by German palaeontologist Ernst Stromer in 1915. 

The original remains were destroyed in World War II, but additional material came to light in the early 21st century.  It is unclear whether one or two species are represented in the fossils reported in the scientific literature. The best known species is S. aegyptiacus from Egypt, although a potential second species, S. maroccanus, has been recovered from Morocco. 

The contemporary spinosaurid genus Sigilmassasaurus has also been synonymized by some authors with S. aegyptiacus, though other researchers propose it to be a distinct taxon. 

RADIOLARIAN TIMEKEEPERS

Anthocyrtium hispidum Haeckel

Radiolarian microfossils, tiny, siliceous, single-celled organisms, make for excellent timekeepers. Think of them as the world's smallest clocks. These wee fellows have been living in the world’s oceans for over 600 million years.

Radiolarians are unicellulars, wee little things with a diameter of 0.1–0.2 mm.

They produce intricate mineral skeletons, typically with a central capsule dividing the cell into the inner and outer portions of endoplasm and ectoplasm.Their beautifully elaborate mineral skeletons are usually made of silica. We find radiolaria as zooplankton throughout the ocean and their skeletal remains make up a large part of the cover of the ocean floor as siliceous ooze.

Due to their rapid turnover of species, they represent an important diagnostic fossil from the Cambrian onwards. Because they occur in continuous and well-dated sequences of rock, they act like a yardstick, helping geologists accurately date rock from around the globe.

In the Upper Triassic rocks, which predate the Triassic / Jurassic Mass Extinction event by about 10 million years, radiolarians are preserved in hundreds of forms. Just above them, in the early Jurassic rock layers laid down about the time of the great die-offs, only a fraction of the previous number of forms are represented. The more recent Jurassic rock shows a rebound of radiolarian diversity, though of course, in different forms, a diversity which continues to flourish and expand in today’s oceans.

Photo: Anthocyrtium hispidum Haeckel, magnification: 400x, bright field (negative image), stacked image Fundort / Site: Barbados Alter / Age: approx. 32-35 million years (late Eocene - early Oligocene) Präparation / Preparation: Andreas Drews

CRETACEOUS DINOSAUR 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 armored dinosaur that date from the very end of the Cretaceous, between 68-66 million years ago.

Imagine a meandering armored tank munching on ferns and low-growing vegetation.

This is a photograph of an ankylosaur trackway filled with water and lit by lamplight along Wolverine River, a research site of Lisa Buckley, one of two magnificent paleontologists working in the area.

Some of the prints contain skin impressions, which is lucky as many of the prints are so shallow that they can only be recognized by the skin impressions.

There are two types of footprints at the Wolverine River Tracksite, the meat-eating theropods (at least four different sizes) and the slow, lumbering plant-eating ankylosaurs. 

Filling the prints with water and using light in a clever way was a genius idea for viewing tracks that are all but invisible in bright sunlight by day.

SUMAS SLIDE FOSSIL SITE

Heidi Henderson at Sumas Slide Eocene Fossil Site