AMMONITES OF THE ARNIOCERAS BEDS

Ammonites (and two gastropods) from the Arnioceras beds near Last Creek in the Canadian Rocky Mountains. The fossils found here are from the Lower Jurassic, Lower Sinemurian, Little Paradise Member of the Last Creek formation. This site is part of the research area for Dr. Howard Tipper, GSC (who is hugely missed) and Dr. Louise Longridge, University of British Columbia.

Several ammonites species can be found here including Arnioceras semicostatum & Arnioceras miserable. The two gastropods you see in the central block have yet to be identified to species. Here's hoping a nice grad student takes an interest. The rare but lovely gastros from this area would make an excellent thesis. Perhaps comparing their distribution to their counterparts in Europe.

CRETACEOUS BONE BEDS

Einiosaurus procurvicornis was a horned dinosaur that roamed North America 74 million years ago. We find their bones in mass bone beds in Cretaceous outcrops of Montana and the Blackfeet Nation. The fossils have been recovered from rich bonebeds, largely consisting of only Einiosaurus fossils. Bonebeds with only one species are called monospecific bonebeds. But why do they occur? ⁣

⁣The most commonly suggested reason is that a herd of animals was suddenly killed by a natural disaster, like a volcanic eruption or flood. 

Their bodies were buried and remained in proximity to each other as they preserved, and today excavations uncover the remains of the unfortunate herd. Multiple other monospecific bonebeds have been found for other species of horned dinosaurs, such as Achelousaurus, causing researchers to suggest some groups of horned dinosaurs did exhibit herding behaviour— and that sometimes they met sudden unfortunate ends. But is sudden mass death from a natural disaster the only reason for monospecific bonebeds? ⁣

⁣Researchers say no. While the monospecific nature is still largely argued to represent herding in many cases, natural disaster is not always the cause of death. Sometimes large numbers of animals die from disease or starvation. Their carcasses could later be pushed together and buried by an event like a mudflow unrelated to their deaths. Their bones could also sit on the surface for years before an event that buries them. ⁣

⁣To understand the cause of a bonebed, researchers look at the bones themselves and the sediment that surrounds them. Bonebeds can tell us a lot about how these animals were living— but there is a lot to be learned from trying to figure out how they died, too. ⁣

Currie, P. J., & Padian, K. (Eds.). (1997). Encyclopedia of dinosaurs. Elsevier. • Rogers, R. R. (1989). Taphonomy of three monospecific dinosaur bone beds in the Late Cretaceous Two Medicine Formation northwestern Montana: Evidence for dinosaur mass mortality related to episodic drought. Graduate Student Theses, Dissertations, & Professional Papers. 5871. • Sampson, S. D. (1995). 

Two new horned dinosaurs from the Upper Cretaceous Two Medicine Formation of Montana; with a phylogenetic analysis of the Centrosaurinae (Ornithischia: Ceratopsidae). Journal of Vertebrate Paleontology, 15(4), 743-760. • Schmitt, J. G., Jackson, F. D., & Hanna, R. R. (2014). Debris flow origin of an unusual late Cretaceous hadrosaur bonebed in the Two Medicine Formation of western Montana. Hadrosaurs. Indiana Press, Bloomington, 486-501.

DINOSAUR TRACKWAY

 

MIGHTY EAGLE: KWIKW (KW-EE-KW)

Bald Eagle / Kwikw / Haliaeetus leucocephalus

A mighty Bald Eagle sitting with wings spread looks to be controlling the weather with his will as much as being subject to it. This fellow has just taken a dip for his evening meal and is drying his feathers in the wind. 

As you can imagine, waterlogged feathers make flight difficult. Their wings are built for graceful soaring and gliding on updrafts of warm air called thermals. 

Their long feathers are slotted, easily separating so air flows smoothly and giving them the added benefit of soaring at slower speeds. 

As well as his wings, this fellow is also drying off his white head feathers. A bald eagle's white head can make it look bald from a distance but that is not where the name comes from. It is from the old English word balde, meaning white.

In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest — or Kwakwaka'wakw, speakers of Kwak'wala — an eagle is known as kwikw (kw-ee-kw) and an eagle's nest is called a kwigwat̕si. 

Should you encounter an eagle and wish to greet them in Kwak'wala, you would just say yo. Yup, just yo. They would like your yo hello better if you offered them some fresh fish. They dine on all sorts of small mammals, fish and birds but are especially fond of pink salmon or ha̱nu'n (han-oon).

These living dinosaurs are a true homage to their lineage. They soar our skies with effortless grace. Agile, violent and beautiful, these highly specialized predators can catch falling prey mid-flight and dive-bomb into rivers to snag delicious salmon. 

Their beauty and agility are millions of years in the making. From their skeletal structure to their blood cells, today’s birds share a surprising evolutionary foundation with reptiles. 

Between 144 million and 66 million years ago, during the Mesozoic era, we see the first birds evolve. Eventually, tens of millions of years ago, an ancient group of birds called kites developed. Like today’s bald eagle, early kites are thought to have scavenged and hunted fish.

About 36 million years ago, the first eagles descended from kites, their smaller cousins. First to appear were the early sea eagles, which — like kites — continued to prey on fish and whose feet were free of feathers, along with booted eagles, which had feathers below the knee. Fossils of Bald Eagles are very rare and date to the late Pleistocene. Eagles are known from the early Pleistocene of Florida, but they are extinct species not closely related to the bald eagle.

Like the kites, bald eagles have featherless feet, but they also developed a range of other impressive adaptations that help them hunt fish and fowl in a watery environment. Each foot has four powerful toes with sharp talons. Tiny projections on the bottom of their feet called “spicules” help bald eagles grasp their prey. A bald eagle also has serrations on the roof of its mouth that help it hold slippery fish, and incredibly, the black pigment in its wing feathers strengthens them against breakage when they dive head first into water.

Obviously, there is much more than their striking white heads that sets these iconic raptors apart from the crowd. Their incredible physiology, built for life near the water, is literally millions of years in the making. 

CANADIAN ROCKIES

CRANEO DE TIGRE DE DIENTES DE SABLE

Machairodus aphanistus, Batallones, Madrid 9 Ma. Vallesiense, Mioceno

STAIRWAY TO HEAVEN

SAUROPTERYGIANS

The sauropterygians are a group of diverse extinct aquatic marine reptiles that developed from terrestrial ancestors soon after the end Permian extinction. We see their earliest rellies about 245 million years ago, during the Triassic.

Their oldest relatives were small, semi-aquatic reptiles with four limbs that were adapted for paddling around in shallow water. By the end of the Triassic, they had grown to much larger animals fully adapted to a life at sea and were incapable of coming to shore.

Throughout the Jurassic and the Cretaceous developed a diverse range of body plans adapted for a life in the water. They went extinct at the end of the Cretaceous along with the dinosaurs.

The best known of the sauropterygians are the long neck Plesiosaurs but this taxon includes a whole host of other interesting Mesozoic marine reptiles. then flourished during the Mesozoic.

Sauropterygians are united by a radical adaptation of their pectoral girdle, designed to support powerful flipper strokes. While Tyrannosaurs ruled the land, and flying reptiles ruled the skies, the mighty Mosasaurs dominated the seas. They were late to the aquatic party, being the last clade to evolve. Photo: By Ryan Somma - PlesiosaurusUploaded by FunkMonk, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=6735975

SILENT WANDERER

CRANEO DE OSO

Ursus spelaeus. Aitzkirri, Guipuzcoa. Pleistoceno superior

BRITISH COLUMBIA'S GREAT BEARS

Hiking in BC, both grizzly and black bear sightings are common. Nearly half the world's population, some 25,000 grizzlies, roam the Canadian wilderness. This photo of Edward (yes, we named him) was taken off the west coast of Vancouver Island by Larissa Harding of Great Bear Nature Tours.

Both bear families descend from a common ancestor, Ursavus, a bear-dog the size of a raccoon who lived more than 20 million years ago. Seems an implausible lineage given the size of their very large descendents.

An average Grizzly weighs in around 800 lbs (363 kg), but a recent find in Alaska tops the charts at 1600 lbs (726 kg). This mighty beast stood 12' 6' high at the shoulder, 14' to the top of his head. It is one of the largest grizzly bears ever recorded. This past month this king of the forest was seen once again in the Washington Cascades -- the first sighting in 50 years.

TORVOSAURUS TANNERI

The genus Torvosaurus includes a unique species of megalosaurid therapod dinosaur.

This fellow is from the Morrison Formation, western United States but his kind spread widely and fossil specimens of the same species have been found in the Lourinha Formation near Lisbon, Portugal. He is currently on display at the Museo Nacional De Ciencias Naturales in Madrid, Spain.

Torvosaurus were one of the largest and most robust carnivores of the Jurassic. These "savage lizards" were true to their name. Skilled hunters, who could grow from 9 to ll meters long, weigh over 2 tons, were bipedal with powerful dentition and strong claws on their forelegs, they ruled the Upper Jurassic.

While currently speculative, there seems to be a high likelihood that these bad boys hunted and dined upon the big sauropods of their time.

BOWRON LAKE CIRCUIT