Wednesday, 23 March 2016
DRAGONFLIES: ANCIENT PREDATORS
Dragonflies, from the order Odonata, have been around for
over 250 million years. The most conspicuous difference in their evolution over
time is the steady shrinking of their wingspan from well over two and a half
feet down to a few inches.
Voracious predators, today they dine on bees, wasps,
butterflies and avoid the attentions of birds and wee lizards -- but back in the day, they had a much larger
selection of meals within their grasp. Time has turned the tables. Small lizards and birds who
today choose dragonflies as a tasty snack used to be their preferred prey.
Monday, 21 March 2016
Wednesday, 16 March 2016
Sunday, 13 March 2016
PALTECHIOCERAS OF WRANGELLIA
Those working in the Jurassic exposures on Vancouver Island are a determined crew. Most of the sedimentary deposits of the Jurassic are exposed in the hard to reach areas between Nootka Sound and Cape Scott.
By the time these ammonites were being buried in sediment, Wrangellia, the predominately volcanic terrane that now forms Vancouver Island and the Queen Charlotte Islands, had made its way to the northern mid-laditudes.
This detail of the Jurassic ammonite, Paltechioceras sp. shot with an ultra-low f-stop, is from an all but inaccessible site in Sayward, Bonanza Group, Vancouver Island.
We did a fossil field trip up there a few years ago with the Courtenay & Qualicum beach crew. The drive up the mountain was thrilling as the road narrowed until it was barely the width of our wheel base. Thrilling to say the least.
By the time these ammonites were being buried in sediment, Wrangellia, the predominately volcanic terrane that now forms Vancouver Island and the Queen Charlotte Islands, had made its way to the northern mid-laditudes.
This detail of the Jurassic ammonite, Paltechioceras sp. shot with an ultra-low f-stop, is from an all but inaccessible site in Sayward, Bonanza Group, Vancouver Island.
We did a fossil field trip up there a few years ago with the Courtenay & Qualicum beach crew. The drive up the mountain was thrilling as the road narrowed until it was barely the width of our wheel base. Thrilling to say the least.
Friday, 19 February 2016
Tuesday, 16 February 2016
Tuesday, 2 February 2016
Saturday, 23 January 2016
LINCOLN CREEK FORMATION: EOCENE-OLIGOCENE BORDER
Fossil crabs, several dozen species of mulluscs including the elusive tusk shell have been found in the fossil exposures of the Lincoln Creek Formation, southern Olympic Peninsula, near the town of Porter, Washington, 46°56'20"N, 123°18'38"W.
It is a site I return to each year to see the erosion and what new specimens have worked their way to the surface.
The whitish strata consists of tuffaceous siltstone and sandstone with concretionary beds throughout. They are slightly older than originally thought, coming in around 37 million-years, straddling the Eocene-Oligocene border. Here a lovely crab, Pulalius vulgaris, sits in the sand. He would be in good company at the site amongst the more common scaphodpod shells and other wee gastropods.
The whitish aragonitic shells of scaphopods are conical and curved with a planispiral curve, looking a bit like an elephant's tusk, hence their common name. They prefer to live on soft substrates in subtidal zones so they are not as abundant or readily visible on our beaches as their gastropods and bivalves compatriots. Tusk shells and their fossil relatives, however, are found commonly in the sediments at Porter and other localities throughout the Pacific Northwest while crabs are found, but more rare.
It is a site I return to each year to see the erosion and what new specimens have worked their way to the surface.
The whitish strata consists of tuffaceous siltstone and sandstone with concretionary beds throughout. They are slightly older than originally thought, coming in around 37 million-years, straddling the Eocene-Oligocene border. Here a lovely crab, Pulalius vulgaris, sits in the sand. He would be in good company at the site amongst the more common scaphodpod shells and other wee gastropods.
The whitish aragonitic shells of scaphopods are conical and curved with a planispiral curve, looking a bit like an elephant's tusk, hence their common name. They prefer to live on soft substrates in subtidal zones so they are not as abundant or readily visible on our beaches as their gastropods and bivalves compatriots. Tusk shells and their fossil relatives, however, are found commonly in the sediments at Porter and other localities throughout the Pacific Northwest while crabs are found, but more rare.
Thursday, 31 December 2015
TUSKS AND BONE: TANGIERS
During the Miocene and Pliocene, 12-1.6 million years ago, a diverse group of extinct proboscideans, elephant-like animals walked the Earth.
Most of these large beasts had four tusks and likely a trunk similar to modern elephants. They were creatures of legend, inspiring myths and stories of fanciful creatures to the first humans to encounter them.
Beyond our neanderthal friends, one such fellow was Quintus Sertorius, a Roman statesman come general, who grew up in Umbria. Born into a world at war just two years before the Romans sacked Corinth to bring Greece under Roman rule, Quintus lived much of his life as a military man far from his native Norcia. Around 81 BC, he travelled to Morocco, the land of opium, massive trilobites and the birthplace of Antaeus, the legendary North African ogre who was killed by the Greek hero Heracles.
The locals tell a tale that Quintus requested proof of Antaeus, hard evidence he could bring back to Rome to support their tales so they took him to a mound at Tingis, Morocco, where they unearthed the bones of a Neogene elephant, Tetralophodon.
Tetralophodon bones are large and skeletons singularly impressive. Impressive enough to be taken for something else entirely. By all accounts these proboscidean remains were that of the mythical ogre Antaeus and were thus reported back to Rome as such. It was hundreds of years later before their true heritage was known.
Monday, 21 December 2015
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