Thursday, 25 April 2019

SOLAR POWERED: TABANIDAE

Horsefly / Diptera / Tabanidae; Latreille, 1802
Horseflies are true flies in the family Tabanidae, order Diptera. They are quite large as flies go and adept little aviators. If you've had the pleasure you'd recall meeting them as they have a nasty bite when they do.

It's the female horseflies that do the chomping, preferring livestock and the occasional human as they hike or enjoy the great outdoors.

Horseflies are sun lovers, they are out in force on nice sunny days and set a healthy bedtime as they become inactive and rest when the sun goes down.

Wednesday, 24 April 2019

VICTORASPIS LONGICORNUALIS

This lovely specimen is an armoured agnatha jawless bony fish, Victoraspis longicornualis, from Lower Devonian deposits of Podolia, Ukraine. The specimen shows both the positive and negative of the fossil in high relief.

Victoraspis longicornualis was named by Anders Carlsson and Henning Bloom back in 2008. The new osteostracan genus and species were described based on material from Rakovets' present-day Ukraine. This new taxon shares characteristics with the two genera Stensiopelta (Denison, 1951) and Zychaspis (Javier, 1985).

Agnatha is a superclass of vertebrates. This fellow looks quite different from our modern Agnatha, which include lamprey and hagfish. Ironically, hagfish are vertebrates who do not have vertebrae. Sometime in their evolution they lost them as they adapted to their environment. Photo: Fossilero Fisherman

Tuesday, 23 April 2019

JOHN DAY FOSSIL BEDS

More than a 100 groups of mammals and a wide variety of plants have been found in the early Miocene, 39-19 million year old, John Day Formation near Kimberly, Oregon. The fossiliferous strata that have yielded beautifully preserved specimens of many of the animals we see domesticated today.

Dogs, cats, swine and horses are common. Oreodonts, camels, rhinoceros and rodents have also been found in this ancient deciduous forested area.

Here my talented young paleontologist cousin Spencer is holding a well preserved Oreodont skull.Many sites in Oregon yield beautifully preserved fossil shells laid down over 60 million years.
The asteroid that hit the Gulf of Mexico at the end of the Cretaceous caused a seafloor rift that split ancient Oregon. The massive hole left behind as the coastal lands slid northward filled in with sediment, refilling the basin.

These marine sediments were uplifted around the time of the birth of Oregon's Coastal Range. Easily collected and identified, as they look very similar to their modern cousins, you can dig for marine fossils all along Oregon's beachfront. I'll post some photos when I return from collecting later this year.

Monday, 22 April 2019

Sunday, 21 April 2019

MUMMIFIED BRANCHIOSTEGUS

An amazing mummified tilefish, Branchiostegus japonicus (Houttuyn, 1782) from Holocene deposits near Shizuoka, Japan. This specimen shows remarkable detail right down to the scales. Quite spectacular, truly.

Modern cousins of this fellow live as far south as the Arafura Sea today. Collection and photos from the deeply awesome Takashi Ito. サンさん、ありがとうございました

Saturday, 20 April 2019

DEEPLY GROOVED DECAPOD

A beautiful example of the "deeply groovy" decapod, Dorippe sinica, from Holocene deposits near Shizuoka, Japan. This regal fellow has a strongly sculptured carapace. He looks like he would have been quite the bruiser moving about on the seafloor looking for tasty snacks. He likely enjoyed just about any form of meat, potentially dining on fish, worms, eggs, squid, starfish or even a few of his slow-moving cousins.

The carapace is deeply grooved with conspicuous wart-like tubercles; anterolateral margin, between the base of the exorbital tooth and cervical groove, smooth, without tubercles or denticles.

The teeth on the lower orbital margin in the cluster. Carpus of cheliped distinctly granulated on the upper surface and with a conspicuous row of granules along the anterior margin. Though missing here, the merus of second and third pereiopods are almost cylindrical. (Türkay 1995). This specimen was collected and is the collection of the deeply awesome Takashi Ito of Japan

Friday, 19 April 2019

FRENCHMAN MOUNTAIN TRILOBITE: BRISTOLIA INSOLENS

Bristolia insolens
A stunning Cambrian trilobite, Bristolia insolens, from Frenchman Mountain near Las Vegas, Nevada.

The mountain provides an example of the Great unconformity with the tilted Paleozoic Tapeats Sandstone underlain by Paleoproterozoic Vishnu Schist. An unconformity is a buried erosional or non-depositional surface separating two strata of different ages. We know when we find these that the sediment was not laid down in a continuous deposition. The range also boasts some of the oldest rock on the North American continent, at about two billion years old.

This spectacular specimen is in the collection of York Yuxi Wang. It is about 4-5cm long; 3-4cm wide.

Thursday, 18 April 2019

Wednesday, 17 April 2019

MOLLUSCA GASTROPODA

Gastropods, or univalves, are the largest and most successful class of molluscs. They started as exclusively marine but have adapted well and now their rank spend more time in freshwater than in salty marine environments.

Many are marine, but two thirds off all living species live in freshwater or on land. Their entry into the fossil record goes all the way back to the Cambrian.

Slugs and snails, abalones, limpets, cowries, conches, top shells, whelks, and sea slugs are all gastropods. They are the second largest class of animals with over 60,000–75,000 known living species.

The gastropods are originally sea-floor predators, though they have evolved to live happily in many other habitats. Many lines living today evolved in the Mesozoic. The first gastropods were exclusively marine and appeared in the Upper Cambrian (Chippewaella, Strepsodiscus).

By the Ordovician, gastropods were a varied group present in a variety of aquatic habitats. Commonly, fossil gastropods from the rocks of the early Palaeozoic era are too poorly preserved for accurate identification. Still, the Silurian genus Poleumita contains fifteen identified species.

Most of the gastropods of the Palaeozoic era belong to primitive groups, a few of which still survive today. By the Carboniferous period many of the shapes we see in living gastropods can be matched in the fossil record, but despite these similarities in appearance the majority of these older forms are not directly related to living forms. It was during the Mesozoic era that the ancestors of many of the living gastropods evolved.

In rocks of the Mesozoic era gastropods are more common as fossils and their shell often very well preserved. While not all gastropods have shells, the ones that do fossilize more easily and consequently, we know a lot more about them. We find them in fossil beds from both freshwater and marine environments, in ancient building materials and as modern guests of our gardens.

Tuesday, 16 April 2019

Monday, 15 April 2019

IDENTIFYING FOSSIL BONE

If you’re wondering if you have Fossil Bone, you’ll want to look for the telltale texture on the surface. It’s best to take the specimen outside and photograph it in natural light.

With fossil bone, you will be able to see the different canals and webbed structure of the bone, sure signs that the object was of biological origin.

As my good friend Mike Boyd notes, without going into the distinction between dermal bone and endochondral bone —  which relates to how they form - or ossify — it's worth noting that bones such as the one illustrated here will usually have a layer of smooth — periosteal — bone on the outer surface and spongy — or trabecular — bone inside.

The distinction can be well seen in the photograph. The partial weathering away of the smooth external bone has resulted in the exposure of the spongy bone interiors. Geographic context is important, so knowing where it was found is very helpful for an ID. Knowing the geologic context of your find can help you to figure out if you've perhaps found a terrestrial or marine fossil. Did you find any other fossils nearby? Can you see pieces of fossil shells or remnants of fossil leaves? Things get tricky with erratics. That's when something has deposited a rock or fossil far from the place it originated. We see this with glaciers. The ice can act like a plow, lifting up and pushing a rock to a new location, then melting away to leave something out of context.

Sunday, 14 April 2019

ZEACRINITES MAGNOLIAEFORMIS

This lovely specimen is Zeacrinites magnoliaeformis, an Upper Mississippian-Chesterian crinoid found by Keith Metts in the Glen Dean Formation, Grayson County, Kentucky, USA.

Crinoids are unusually beautiful and graceful members of the phylum Echinodermata. They resemble an underwater flower swaying in an ocean current. But make no mistake they are marine animals. Picture a flower with mouth on the top surface that is surrounded by feeding arms. Awkwardly, add an anus right beside that mouth. That's him!

Crinoids with root-like anchors are called Sea Lilies. They have graceful stalks that grip the ocean floor. Those in deeper water have longish stalks up to 3.3 ft or a meter in length.

Then there are other varieties with that are free-swimming with only vestigial stalks. They make up the majority of this group and are commonly known as feather stars or comatulids.

Unlike the sea lilies the feather stars can move about on tiny hook like structures called cirri. It is this same cirri that allows crinoids to latch to surfaces on the sea floor.

Like other echinoderms, crinoids have pentaradial symmetry. The aboral surface of the body is studded with plates of calcium carbonate, forming an endoskeleton similar to that in starfish and sea urchins.

These make the calyx somewhat cup-shaped, and there are few, if any, ossicles in the oral (upper) surface called a tegmen. It is divided into five ambulacral areas, including a deep groove from which the tube feet project, and five interambulacral areas between them. The anus, unusually for echinoderms, is found on the same surface as the mouth, at the edge of the tegmen.

Crinoids are alive and well today. They are also some of the oldest fossils on the planet. We have lovely fossil specimens dating back to the Ordovician.

Saturday, 13 April 2019

CROCODILIAN UPSTARTS: THE CRUROTARSANS

Dinosaurs, long hailed as the rulers of the Triassic almost lost the title belt to a group of crocodilian upstarts, the crurotarsans. In a short-lived battle for survival, geologically speaking, the two groups ran head-to-head for about thirty million years.

The Crurotarsi or "cross-ankles" as they are affectionately known, are a group of archosaurs - formerly known as Pseudosuchians when paleontologist Paul Serono, the darling of National Geographic, renamed them for their node-based clade in 1991. Image: By Nobu Tamura (http://spinops.blogspot.com) - Own work, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=19459679

Thursday, 11 April 2019

HEXACORALLIA

Hexacorallia is a subclass of Anthozoa comprising approximately 4,300 species of aquatic organisms formed of polyps, generally with six-fold symmetry. Their temporal range is from the Fortunian to the Holocene. The subclass includes all of the stony corals, most of which are colonial and reef-forming, as well as all sea anemones, and zoanthids, arranged within five extant orders.

The hexacorallia are distinguished from another subclass of Anthozoa, Octocorallia, in having six or fewer axes of symmetry in their body structure; the tentacles are simple and unbranched and normally number more than eight. These organisms are formed of individual soft polyps which in some species live in colonies and can secrete a calcite skeleton. As with all Cnidarians, these organisms have a complex life cycle including a motile planktonic phase and a later characteristic sessile phase. Hexacorallia also includes the significant extinct order of rugose corals.

Wednesday, 10 April 2019

AURELIA AURITA: MOON DANCERS

Moon Jelly Fish / Aurelia Aurita
Aurelia aurita (also called the common jellyfish, moon jellyfish, moon jelly or saucer jelly) is a widely studied species of the genus, Aurelia. All species in the genus are closely related, and it is difficult to identify Aurelia medusae without genetic sampling; most of what follows applies equally to all species of the genus.

The genus Aurelia is found throughout most of the world's oceans, from the tropics to as far north as latitude 70° north and as far south as 40° south. The species Aurelia aurita is found along the eastern Atlantic coast of Northern Europe and the western Atlantic coast of North America in New England and Eastern Canada. In general, Aurelia is an inshore genus that can be found in estuaries and harbours.

The genus Aurelia is found throughout most of the world's oceans, from the tropics to as far north as latitude 70° north and as far south as 40° south. The species Aurelia aurita is found along the eastern Atlantic coast of Northern Europe and the western Atlantic coast of North America in New England and Eastern Canada. In general, Aurelia is an inshore genus that can be found in estuaries and harbours.

Tuesday, 9 April 2019

OH MAXIMUS: ISOTELUS REX

This lovely big fella is Isotelus rex from Churchill, Manitoba, Canada. He was found along the Hudson Bay and is the largest complete trilobite ever found. Isotelus is a genus of asaphid trilobites, an extinct group of arthropods, from the middle and upper Ordovician

Discovered by a paleo dream team, including the deeply awesome, Dave Rudkin, assistant curator of paleobiology at the Royal Ontario Museum, along with Robert Elias (Project Lead), University of Manitoba, Graham Young (Project Lead), associate curator of geology at the Manitoba Museum of Man and Nature (and adjunct professor at the University of Manitoba) and Edward Dobrzanski, Manitoba Museum during a long-term field project in 1998-1999.

The specimen measures in at a whopping 28 inches in length and is 70 percent larger than the previous record holder and warranted a new species name. The image here shows one of several replicas (casts), not the actual holotype specimen which is on exhibit at the Manitoba Museum.

There is a second complete specimen (430 mm in length) of Isotelus rex in the collections of the Geological Survey of Canada (GSC 85292 - a designated paratype). As with many such projects, financial contributions make field work and research possible. A nod to the Natural Sciences and Engineering Research Council of Canada, the University of Manitoba, the Manitoba Museum Foundation nd the Royal Ontario Museum Foundation.

Kudos as well to field crew, David Wright, Curtis Moffat and Janis Klapecki. You arrived four hundred and forty-five million years too late for sunscreen and tropical weather.

In the prophetic words of Eddard Stark, "Winter is Coming." And so it did to the Canadian prairies. Thank you to everyone involved for enduring the frozen cold, wind, rains and hail of northern Manitoba. For those who haven't had the pleasure, dear Manitoba gets blasted by cold Arctic high-pressure that drops it to a frigid -47.2 Celsius. That's a sweet, sweet -52 with wind chill.

Paper: Rudkin, D.A.; Young, G.A.; Elias, R.J.; Dobrzanski, E.P. (2003). "The World's biggest Trilobite: Isotelus rex new species from the Upper Ordovician of northern Manitoba, Canada". Palaeontology. 70 (1): 99–112. doi:10.1666/0022-3360(2003)077<0099:twbtir>2.0.CO;2. ISSN 0022-3360.

Photo credit: Mike Beauregard from Nunavut, Canada. Cast of Isotelus rex. Churchill Manitoba. 2 foot long replica housed at the University of Manitoba. Original specimen is in the Manitoba Museum. The original specimen was recovered the intertidal zone of Hudson Bay.

Monday, 8 April 2019

OREGON PALEONTOLOGY

Driving down the Oregon coast, you see large basalt sentinels left stranded on the beaches. The surf rubs at them slowly eroding a story that extends into our geologic past.

The rugged landscape of Oregon was shaped over millions of years. Fire, floods, earthquakes and volcanic eruptions —  driven by the collision of an oceanic and continental plate — each had a hand in helping to shape this beautiful part of the world. The ground here has been moving and shifting on a steady northeast direction for several hundred million years and continues today.

Oregon's geologic record extends back to the Devonian. Oregon had been mostly submerged hidden beneath the depths of an ancient ocean. The centre of the state boasts the oldest rocks. Near Suplee, Oregon snuggled up against the Malheur National Forest you can find Devonian limestones with a lovely of shallow-water marine invertebrates. Look for corals and brachiopod who made a living in Devonian seas far from where they rest today.

In the Carboniferous period, a series of volcanic archipelagos formed in Oregon. The islands enjoyed a warm, wet, terrestrial environments. Think of the Mississipi today. Fossils in Oregon's oldest floral assemblage, dating to the Late Carboniferous, were built on a lagoon ecosystem. The fossil fauna here include horsetails, ferns, scale trees, and conifer tree seeds. Formations of similar age also include shallow-water invertebrates telling us that Oregon's volcanic islands were surrounded by coral reefs.

Oregon remained mostly submerged until the Paleocene. Oregon was covered by seaways and volcanic islands during the Mesozoic. We find marine plants, invertebrates, ichthyosaurs, pterosaurs, and traces such as invertebrate burrows.

During the Cenozoic, Oregon's climate gradually cooled and eventually yielded the environments now found in the state. The era's fossils include marine and terrestrial plants, invertebrates, fish, amphibians, turtles, birds, mammals, and traces such as eggs and animal tracks.

Sediment records show that Oregon remained mostly submerged until the Paleocene period. The state's earliest fossil record includes plants, corals, and conodonts.

Oregon was covered by seaways and volcanic islands during the Mesozoic era. Fossils from this period include marine plants, invertebrates, ichthyosaurs, pterosaurs, and traces such as invertebrate burrows.

During the Cenozoic, Oregon's climate gradually cooled and eventually yielded the environments now found in the state. The era's fossils include marine and terrestrial plants, invertebrates, fish, amphibians, turtles, birds, mammals, and traces such as eggs and animal tracks.

Reference: https://www.oregongeology.org/pubs/ims/ims-028/index.htm

Tuesday, 2 April 2019

CROCUTA CROCUTA

Female Spotted Hyena / Sub-Saharan Africa
This lovely lady is a spotted hyena. While she looks like a large dog, she shares more similarities with our large cats, lions and tigers.

Like all her kin, she's a wonderful hunter either with her pack or out solo. While portrayed as scavengers, those who've seen them in the wild know that she's a good little hunter and not a picky eater. Hyenas snack on a varied selection of birds, lizards, snakes, fish and insects over their long lives. Most live about 25 years and are quite social animals. They live in large groups called clans, some up to 75-80 individuals. They eat larger game as well, often hunting with their clan packs to take down zebra, antelope, wildebeest and even young hippos.

Spotted hyenas are mammals in the Family Hyaenidae. They roam the tropical grasslands, woodlands and savanna of Africa. The females are the larger of the species, weighing up to 82 kg and growing up to 2 metres long and are the leaders of the group. Each clan is led by one alpha female who rules the roost and still takes time out to have one ot cubs a year. They are the original working moms.

Monday, 1 April 2019

PALEO PARENTING: NOTHOSAURS

In Sauropterygia, a diverse group of Mesozoic marine reptiles, fossil evidence of viviparity (live‐bearing) only exists for Pachypleurosauria and Plesiosauria, and was assumed to also be the case for nothosaurs.

Previous studies have successfully applied an extant squamate model to sauropterygian life‐history traits. In extant squamates, oviparity and viviparity are associated with differences in life‐history trait combinations.

A paper released in March 2019, in the journal Palaeontology, sheds light on this view. Griebeler et al. have establish growth curves for Nothosaurus specimens based on their humeral histology.

They analyzed life‐history traits derived from these curves and compared inferred traits to those of modern squamates and pachypleurosaurs to assess their reproduction mode.

Their data shows birth to adult size ratios (i.e. birth size divided by the mother's size) provides a good estimate of clutch sizes in extant squamates and in viviparous extinct marine reptiles, but these ratios cannot discriminate viviparous and oviparous squamates.

Thus, large ratios do not indicate viviparity in fossil taxa to which the extant squamate model is applicable.

Applying differences in birth size, age at maturation, and maximum longevity that are observed between extant viviparous and oviparous squamates to our Nothosaurus sample, they identified 7 out of 24 specimens as being potentially viviparous.

Conversely, they suggested oviparity for many nothosaurs but also for many pachypleurosaur samples.

Under the assumption that the entire clade Pachypleurosauria was viviparous, the majority of nothosaurs would also have been viviparous as they comprised trait combinations similar to those seen in pachypleurosaurs.

Overall, this suggests that within nothosaurs and pachypleurosaurs both reproduction modes existed in different taxa.

Saturday, 30 March 2019

TAKING IN THE VIEW

We soak up the breathtaking views after a long morning's paddle. The east and south sides of our route are bound by the imposing white peaks of the Cariboo Mountains, the northern boundary of the Interior wet belt, rising up across the Rocky Mountain Trench, and the Isaac Formation, the oldest of seven formations that make up the Cariboo Group.

Some 270 million years ago, the rock that would become the Cariboo Mountains and form the lakes and valleys of Bowron was far out in the Pacific Ocean, down near the equator. With tectonic shifting, these rocks drifted north-eastward, riding their continental plate, until they collided with and joined the Cordillera in what is now British Columbia. Continued pressure and volcanic activity helped create the tremendous slopes of the Cariboo Range we see today with repeated bouts of glaciation during the Pleistocene carving their final shape. Warm and dry with bellies filled full of soup and crisps, we head back out to explore more of nature's bounty.

Wednesday, 27 March 2019

Monday, 25 March 2019

ODE TO OECANTHUS


Out in the woods and wondering what the temperature is? Slip down to the nearest stand of deciduous trees to search for the wee Snowy Tree Cricket, Oecanthus Fultoni, part of the order Orthoptera.
Snowy Tree Crickets and their cousins double as thermometers and wee garden predators, dining on aphids and other wee beasties.

Weather conditions, both hot and cold, affect the speed at which they rub the base of their wings together and consequently regulate their rate of chirping. Listen for their tell-tale high pitch triple chirp sound in the early evening. Being in Canada, our crickets chirp in Celsius. Simply count the number of chirps over a seven second period and add five to learn your local temperature.

If didn't bring your calculator with you into the woods and you're still operating in old-skool Fahrenheit, ie. those in the United States, the Bahamas, Belize, the Cayman Islands and Liberia can use this handy conversion. Double the temperature in Celsius, add 32 you'll get the approximate temperature in Fahrenheit.

Sunday, 17 March 2019

Saturday, 16 March 2019

FEMALE MACROCONCH

This sweet beauty with lovely colouring is a Hoploscaphites nebrascensis (Owen, 1852) macroconch. This is the female form of the ammonite that has a larger shell than the male, or microconch.

Hoploscaphites nebrascensis is an upper Maastrichtian species and index fossil. It marks the top of ammonite zonation for the Western Interior. This species has been recorded from Fox Hills Formation in North and South Dakota as well as the Pierre Shale in southeastern South Dakota and northeastern Nebraska.

It is unknown from Montana, Wyoming, and Colorado due to the deposition of coeval terrestrial units. It has possibly been recorded in glacial deposits in Saskatchewan and northern North Dakota, but that is hearsay. Outside the Western Interior, this species has been found in Maryland and possibly Texas in the Discoscaphites Conrad zone. This lovely one is in the collection of the deeply awesome (and enviable) José Juárez Ruiz. A big thank you to Joshua DrSlattmaster J Slattery for his insights on this species.

Friday, 15 March 2019

Thursday, 14 March 2019

URSUS CURIOUS

A young Black Bear cub, Ursus americanus, checking out the view from a tree branch. His mamma is likely very near by as they keep an eye on the cubs, helping to feed, dry and protect them from danger.

Full grown, this fuzzy fellow will be able to run 48 kilometres or 30 miles an hour. They like to swim and hunt for fish, berries and roots. They will also dine on insects, deer, moose and whatever they can scavenge in the forest. 

We are blessed to have them living amongst us today on the rugged west coast of British Columbia. 

In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, this little cutie is t̕ła'yi — a lovely, playful black bear.

Wednesday, 13 March 2019

Monday, 11 March 2019

DEVONIAN FISH PODOLIA, UKRAINE

A Devonian fish mortality plate showing all lower shields of Zenaspis podolica (Lankester, 1869) and Stensiopelta pustulata (and potentially Victoraspis longicornualis) from Lower Devonian deposits of Podolia, Ukraine.

Zenaspis is an extinct genus of jawless fish which thrived during the early Devonian. Being jawless, Zenaspis was probably a bottom feeder, snicking on debris from the seafloor.

The lovely 420 million-year-old plate you see here is from Podolia or Podilia, a historic region in Eastern Europe, located in the west-central and south-western parts of Ukraine, in northeastern Moldova. Podolia is the only region in Ukraine where Lower Devonian remains of ichthyofauna can be found near the surface.

For the past 150 years, vertebrate fossils have been found in more than 90 localities situated in outcrops along banks of the Dniester River and its northern tributaries, and in sandstone quarries. At present, the faunal list of Early Devonian agnathans and fishes from Podolia number 72 species, including 8 Thelodonti, 39 Heterostraci, 19 Osteostraci, 4 Placodermi, 1 Acanthodii, and 1 Holocephali (Voichyshyn 2001a, modified).

In Podolia, Lower Devonian redbeds strata (the Old Red Formation or Dniester Series) are up to 1800 m thick and range from Lochkovian to Eifelian in age (Narbutas 1984; Drygant 2000, 2003). In their lower part (Ustechko and Khmeleva members of the Dniester Series) they consist of multicoloured, mainly red, fine-grained cross-bedding massive quartz sandstones and siltstones with seams of argillites (Drygant 2000).

We also see fossils of Zenaspis in the early Devonian of Western Europe. Both Zenaspis pagei and Zenaspis poweri can be found up to 25 centimetres long in Devonian outcrops of Scotland.

Reference: Voichyshyn, V. 2006. New osteostracans from the Lower Devonian terrigenous deposits of Podolia, Ukraine. Acta Palaeontologica Polonica 51 (1): 131–142. Photo care of the awesome Fossilero Fisherman.

Sunday, 10 March 2019

Saturday, 9 March 2019