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.

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

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.

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.