40 DEGREES OF LATITUDE: THE ROCKIES

Images of darkened valleys, golden late summer light, icy-blue glaciers, white caps on an endless Pacific, small, hardy, yet perfect alpine flowers, spring to mind and each carries a small element but doesn't quite capture it. Heck, even our dog parks are ruggedly beautiful and by the sheer number of visits, would certainly define a large part of my west coast experience.

But the niggling thought is still there. Is there one a single element I could name that epitomizes this vast, diverse landscape? Sea to Sky, lakes to mountains, I've kayaked, hiked, sailed and lovingly explored a great deal of it. Through 40 degrees of latitude, from Yukon to Mexico, the Rocky Mountains are North America's geographic backbone.

This is the Great Continental Divide, where the interminable flatness of the interior collides with the Western Cordillera, a major mountain system of the world. From the highest ridges of the Rockies, the rivers flow to opposite corners of the land, north to the Beaufort Sea, south to the Gulf of Mexico, east to Hudson Bay and west to the Pacific.

KWAS'KWAS: OUR BEAUTIFUL BLUE JAYS

If you live in North American, there is a high probability that you have seen or heard the bird song of the Blue jay, Cyanocitta cristata (Linnaeus, 1758).

Blue Jays are in the family Corvidae — along with crows, ravens, rooks, magpies and jackdaws. They belong to a lineage of birds first seen in the Miocene — 25 million years ago. 

These beautifully plumed, blue, black and white birds can be found across southern Canada down to Florida. The distinctive blue you see in their feathers is a trick of the light. Their pigment, melanin, is actually a rather dull brown. The blue you see is caused by scattering light through modified cells on the surface of the feather as wee barbs.

Blue jays like to dine on nuts, seeds, suet, arthropods and some small vertebrates. 

If you are attempting to lure them to your yard with a bird feeder, they prefer those mounted on trays or posts versus hanging feeders. They will eat most anything you have on offer but sunflower seeds and peanuts are their favourites. 

They have a fondness for acorns and have been credited with helping expand the range of oak trees as the ice melted after the last glacial period.  

Their Binomial name, Cyanocitta cristata means, crested, blue chattering bird. I might have amended that to something less flattering, working in a Latin word or two for shrieks and screams — voce et gemitu or ululo et quiritor. While their plumage is a visual feast, their bird chatter leaves something to be desired. 

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest and my family, a Blue Jay is known as kwa̱skwa̱s. 

The Kwak’wala word for blue is dzasa and cry is ḵ̕was'id. For interest, the word for bird song in Kwak'wala is t̕sa̱sḵwana. Both their songs and cries are quite helpful if you are an animal living nearby and concerned about predators. 

FOSSIL FIELD TRIP VIA JET RANGER

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