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Meet Saltriovenator: Oldest Known Big Predatory Dinosaur

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Saltriovenator was likely covered with filamentous protoplumage. The presence of horns on the lacrymal and nasal bones is inferred from its close kinship with dinosaurs which possess those cranial onamentation. Credit: Davide Bonadonna.

An artist’s rendering of Saltriovenator includes filamentous protoplumage and horns, the latter suggested by its evolutionary links to species with similar ornamentation. (Credit: Davide Bonadonna)

Paleontologists working in northern Italy have announced the oldest large-size predatory dinosaur known to the fossil record. Saltriovenator zanellai weighed about a ton and, at nearly 200 million years old, predates more famous megapredators by at least 25 million years.

Saltriovenator’s bones are also the first dinosaur remains to preserve evidence of marine animals that gnawed on its carcass. The biggest thing about S. zanellai, however, may be its hands: The animal’s fingers could solve a long-running debate about how bird wings evolved. 

Saltriovenator would be a source of significant national pride at any size: It’s the first Jurassic dinosaur ever found in Italy. But the animal’s robust build and estimated length of more than 24 feet make it especially noteworthy, because other predatory dinosaurs of the period were typically less stocky and much smaller. Even bigger news: Researchers believe the Saltriovenator speciman was a sub-adult, with plenty of growing left to do.

Dined-Upon After Death

The first pieces of the new dinosaur were found in a quarry in 1996 by amateur fossil enthusiast Angelo Zanella. Alas, quarrying explosives had blown apart the fossiliferous layers of rock, splintering many of the bones. Painstaking excavation, preparation and analysis of the material took decades, which is why the find is only being formally named and described now.

Skeletal reconstruction of Saltriovenator zanellai, made by comparing the shape and proportions of the known elements (in orange) with those of more complete skeletons of related species. For scale is Mr. Angelo Zanella (1.67 m tall), who found the dinosaur now named after him. Credit: Marco Auditore

This skeletal reconstruction of S. zanellai uses Angelo Zanella for scale: the amateur paleontologist discovered the animal that now bears his name. Fossil fragments shown in orange belong to Saltriovenator; the rest of the body was determined comparing those pieces with more complete skeletons of related species. (Credit: Marco Auditore)

Eventually, the team recovered 132 fragments, enough to piece together 64 complete or partial bones and confirm nearly all the material was from a single individual. A single tooth and a jaw fragment found with Saltriovenator turned out to be from a bony fish, which hints at the dinosaur’s watery resting place — and a fascinating aspect of the find.

Researchers confirmed at least 30 bore marks on the bones from a variety of marine invertebrates that had nibbled on the carcass. It’s the first time this kind of marine bioerosion has been found on a dinosaur. It suggests that Saltriovenator’s carcass sank to the bottom of a shallow marine basin or similar body of water, and remained partially exposed to scavengers for some time.

Jurassic Spark

Finding a large-body predatory dinosaur from the Early Jurassic could help explain a curious trend in the fossil record from this period. Saltriovenator belongs to one of the major dinosaur lineages: Theropoda. Theropods were almost exclusively meat-eaters, and preyed on another major lineage, the herbivorous sauropodomorphs. The most famous of the sauropodomorphs were also among the last of their line to evolve, and include the aptly-named titanosaurs.

But let’s back up to the Late Triassic, which predates the Jurassic Period. At this time, well over 200 million years ago, most sauropodomorphs were significantly smaller than the giants that evolved much later. (There are a couple exceptions, such as Argentina’s Ingentia prima, described earlier this year.) Then, suddenly, in the Early Jurassic — when Saltriovenator was around — the sauropodomorphs start getting bigger and bigger.

A number of explanations for this trend toward gigantism have been proposed, but the discovery of Saltriovenator suggests that predator and prey may have been engaged in a size-based arms race during the Early Jurassic.

Winging It

While its size in life (and the evidence of what ate it after death) are intriguing, the most scientifically significant thing about Saltriovenator may be the story told in its fingers. Birds are the lone surviving dinosaur lineage; more specifically, they’re the last theropod dinosaurs around. How the earliest birds evolved wings is one of the most contentious hot spots in the field, right up there with the evolution of feathers.

Some researchers believe that bird wings are the result of the first, second and third digits of the theropod hand becoming fused; others think the fusion was of the second, third and fourth digits. According to the authors of today’s study, Saltriovenator, which had a stubby fourth digit, provides supporting evidence for the hypothesis that modern bird wings evolved from the first, second and third digits of a distant theropod ancestor.

This digit debate may sound like a minor issue to casual dinosaur fans, but supporting evidence for either hypothesis can be found in both the fossil record and developmental research into modern bird embryos. Figuring out how bird wings evolved could provide us with a better idea of how specific traits emerge in a species.

The open-access study appears today in PeerJ.

Simplified evolutionary tree of predatory dinosaurs (theropods). Saltriovenator predates the massive meat-eating dinosaurs by over 25 million years: it is the oldest known ceratosaurian, and the world’s largest predatory dinosaur from the Lower Jurassic. During the Jurassic, the three- fingered tetanuran theropods appeared, which gave rise to birds. Credit: Andrea Cau.

Saltriovenator is the world’s biggest Early Jurassic predatory dinosaur, showing up in the fossil record more than 25 million years before other predators of a similar size. Its forelimbs had four digits, which helped authors determine it was not a three-fingered tetanuran dinosaur, the lineage from which birds evolved. Despite being merely a distant cousin of birds, Saltriovenator’s anatomy may solve a debate over how those living dinosaurs came to be. (Credit: Andrea Cau)

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Ecology

Yukon and Northern BC First Nations tackle climate change using Indigenous knowledge and science

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YUKON, June 18, 2021 /CNW/ – The Government of Canada is working together in partnership with Indigenous and Northern communities in finding solutions to adapt to the impacts of climate change in the North.

Today, Minister of Northern Affairs, Daniel Vandal, along with Parliamentary Secretary to the Minister of Economic Development and Official Languages (Canadian Northern Economic Development Agency), Larry Bagnell, highlighted progress on three unique, Indigenous-led projects that are helping communities in Yukon and Northern British Columbia adapt to the challenges posed by climate change.

The Minister and Parliamentary Secretary met virtually with Carcross/Tagish First Nation (C/TFN) to learn about their community-led climate change monitoring program. C/TFN has partnered with Tsay Keh Dene Nation (TKDN) and Chu Cho Environmental of Prince George, British Columbia, to build a community-led monitoring project that examines environmental data and Indigenous knowledge to create a holistic picture of how the climate is changing across C/TFN and TKDN traditional territories. The project combines tracking of current and historical climate trends with knowledge shared by Elders while also providing opportunities for youth mentorship and climate change awareness.

The Taku River Tlingit First Nation (TRTFN) is also leading a unique project to assess the impacts of climate change within their traditional territory. Climate change is causing many of the culturally significant ice patches to melt, exposing organic artifacts to oxygen and leading to rapid deterioration. The TRTFN ice patch mapping project will involve performing archaeological assessments to prevent the degradation of artifacts. Research will be guided by traditional knowledge, Elders and oral histories, when available, and heavily involve community, Elders, youth and Knowledge Keepers.

The Pelly Crossing Selkirk Development Corporation is leading the Selkirk Wind Resource Assessment project through the installation of a Sonic Detection and Ranging (SODAR) system. The initiative includes a feasibility study leading up to the construction of a renewable energy facility, including wind, solar and battery energy storage. Expanding clean energy within the region will have direct benefits for communities, including reduced reliance on diesel, job creation and revenue generation for Selkirk First Nation. 

These projects are delivering important environmental, social and economic benefits that lead to healthier, more sustainable and resilient communities across Yukon and Northern British Columbia. They also build community clean energy capacity and help to avoid the impacts of climate change.

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Ecology

Atlantic Provinces Ready For Aquaculture Growth

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Aquaculture is an important economic driver for rural, coastal and Indigenous communities, and Atlantic Canada is well positioned to increase aquaculture production as global demand for sustainably sourced seafood grows.

That is why the ministers responsible for aquaculture in the Atlantic provinces have agreed to the ongoing development and management of their industries based on common principles. A new memorandum of understanding has been signed by the four ministers, which extends the previous agreement signed in 2008.

“In a time when food security is especially important, it is good to see our aquaculture industry has grown steadily and is poised for continued growth in 2021 based on environmentally responsible, science-based policies and practices,” said Keith Colwell, Minister of Fisheries and Aquaculture for Nova Scotia. “Our Atlantic partnership continues to help the industry grow sustainably.”

Cooperation between the provinces and the aquaculture industry has led to improvements in pest management, environmentally sustainable aquaculture methods, aquatic animal health and policies to support the shared use of marine and freshwater resources. It also aims to align regulation and policy between the provinces to make the regulatory requirements easier to understand by industry and the public.

Each province has a comprehensive and robust legislative and regulatory framework to ensure environmental sustainability, economic prosperity and public accountability. The provinces update their legislation and regulations regularly. Nova Scotia revamped its regulatory framework in 2015; New Brunswick received Royal Assent for a new Aquaculture Act in 2019 and is working on the supporting regulations; Newfoundland and Labrador completely revised its aquaculture policy in 2019; and Prince Edward Island has recently drafted a new Aquaculture Act.

The ministers have agreed to continue to use science-based evidence for management decisions, thereby increasing public and investor confidence in the Atlantic Canadian aquaculture industry.

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Ecology

COMING SOON: A Healthy Environment and a Healthy Economy 2.0

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We all want the same thing: a clean and responsible energy future for our children and future generations while continuing to enjoy a high standard of living.

On December 11, 2020, the Prime Minister announced a new climate plan which he claimed will help achieve Canada’s economic and environmental goals.

The proposed plan by Environment and Climate Change Canada (ECCC) entitled “A Healthy Environment and a Healthy Economy” will have an initial investment of $15 billion of taxpayer’s money. It is built on 5 pillars of action:

  1) Making the Places Canadians Live and Gather More Affordable by Cutting Energy Waste

2) Making Clean, Affordable Transportation and Power Available in Every Community

3) Continuing to Ensure Pollution isn’t Free and Households Get More Money Back

4) Building Canada’s Clean Industrial Advantage

5) Embracing the Power of Nature to Support Healthier Families and More Resilient Communities  

In my paper, “A Healthy Environment and a Healthy Economy 2.0” I will objectively critique each pillar in the government’s new climate plan and provide alternative solutions to the same issues.

  This is an alternative plan that supports workers, protects lower income earners and creates economic growth while respecting the environment and focusing on the dignity of work.

  This plan abandons virtue-signaling projects and relies on Canadian ingenuity to build our economy and restore Canada’s role of responsible leadership in the world.

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