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“Astonishing” 500-Million-Year-Old Fossilized Brains Prompt a Rethink of the Evolution of Insects and Spiders – SciTechDaily

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Stanleycaris hirpex. Credit: Sabrina Cappelli © Royal Ontario Museum

An ancient radiodont predator with three eyes reveals key information about the evolution of the arthropod body plan.

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New research based on a cache of fossils that contains the brain and nervous system of a half-billion-year-old marine predator from the Burgess Shale called Stanleycaris has been revealed by the Royal Ontario Museum (ROM). Belonging to an ancient, extinct offshoot of the arthropod evolutionary tree called Radiodonta, Stanleycaris is distantly related to modern insects and spiders. These results shed light on the evolution of the arthropod brain, vision, and head structure.

“The details are so clear it’s as if we were looking at an animal that died yesterday.”

Joseph Moysiuk

The findings were announced in the research paper, “A three-eyed radiodont with fossilized neuroanatomy informs the origin of the arthropod head and segmentation,” published on July 5, 2022, in the journal Current Biology.

Stanleycaris hirpex Fossil Specimens

Pair of fossil specimens of Stanleycaris hirpex, specimen ROMIP 65674.1-2. Credit: Photo by Jean-Bernard Caron, © Royal Ontario Museum

What has scientists most excited is what’s inside Stanleycaris’ head. The remains of the brain and nerves are still preserved after 506 million years in 84 of the fossils.

“While fossilized brains from the Cambrian Period aren’t new, this discovery stands out for the astonishing quality of preservation and the large number of specimens,” said Joseph Moysiuk, lead author of the research and a University of Toronto (U of T) PhD Candidate in Ecology and Evolutionary Biology, based at the Royal Ontario Museum. “We can even make out fine details such as visual processing centers serving the large eyes and traces of nerves entering the appendages. The details are so clear it’s as if we were looking at an animal that died yesterday.”

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Turntable animation of Stanleycaris hirpex, including transparency to show internal organs. Credit: Animation by Sabrina Cappelli © Royal Ontario Museum

The new fossils reveal that the brain of Stanleycaris was composed of two segments, the protocerebrum, connected with the eyes, and the deutocerebrum, connected with the frontal claws.

“We conclude that a two-segmented head and brain has deep roots in the arthropod lineage and that its evolution likely preceded the three-segmented brain that characterizes all living members of this diverse animal phylum,” added Moysiuk.

In present-day arthropods like insects, the brain consists of protocerebrum, deutocerebrum, and tritocerebrum. While the difference in a segment may not sound game-changing, it in fact has radical scientific implications. Since repeated copies of many arthropod organs can be found in their segmented bodies, figuring out how segments line up between different species is key to understanding how these structures diversified across the group.

“These fossils are like a Rosetta Stone, helping to link traits in radiodonts and other early fossil arthropods with their counterparts in surviving groups.”

Reconstruction of Stanleycaris hirpex

Reconstruction of a pair of Stanleycaris hirpex; upper individual has transparency of the exterior increased to show internal organs. Nervous system is shown in light beige, digestive system in dark red. Credit: Illustration by Sabrina Cappelli © Royal Ontario Museum

In addition to its pair of stalked eyes, Stanleycaris possessed a large central eye at the front of its head, a feature never before noticed in a radiodont. “The presence of a huge third eye in Stanleycaris was unexpected. It emphasizes that these animals were even more bizarre-looking than we thought, but also shows us that the earliest arthropods had already evolved a variety of complex visual systems like many of their modern kin” said Dr. Jean-Bernard Caron, ROM’s Richard Ivey Curator of Invertebrate Palaeontology, and Moysiuk’s PhD supervisor. “Since most radiodonts are only known from scattered bits and pieces, this discovery is a crucial jump forward in understanding what they looked like and how they lived,” added Caron, who is also an Associate Professor at the U of T, in Ecology & Evolution and Earth Sciences.

Nervous System From Fossils of Stanleycaris

Paper summary, showing the interpretation of the nervous system from fossils of Stanleycaris and implications for understanding the evolution of the arthropod brain. The brain is represented in red and the nerve cords in purple. Credit: Photo by Jean-Bernard Caron © Royal Ontario Museum

In the Cambrian Period, radiodonts included some of the biggest animals around, with the famous “weird wonder” Anomalocaris reaching up to at least 1 meter in length. At no more than 20 cm long, Stanleycaris was small for its group, but at a time when most animals grew no bigger than a human finger, it would have been an impressive predator. Stanleycaris’ sophisticated sensory and nervous systems would have enabled it to efficiently pick out small prey in the gloom.

Stanleycaris hirpex Reconstruction

Reconstruction of Stanleycaris hirpex. Credit: Art by Sabrina Cappelli © Royal Ontario Museum

With large compound eyes, a formidable-looking circular mouth lined with teeth, frontal claws with an impressive array of spines, and a flexible, segmented body with a series of swimming flaps along its sides, Stanleycaris would have been the stuff of nightmares for any small bottom dweller unfortunate enough to cross its path.

About the Burgess Shale

For this research, Moysiuk and Caron studied a previously unpublished collection of 268 specimens of Stanleycaris. The fossils were primarily collected in the 1980s and 90s from rock layers above the famous Walcott Quarry site of the Burgess Shale in Yoho National Park, B.C., Canada, and are part of the extensive collection of Burgess Shale fossils housed at ROM.

The Burgess Shale fossil sites are located within Yoho and Kootenay National Parks and are managed by Parks Canada. Parks Canada is proud to work with leading scientific researchers to expand knowledge and understanding of this key period of earth history and to share these sites with the world through award-winning guided hikes. The Burgess Shale was designated a UNESCO World Heritage Site in 1980 due to its outstanding universal value and is now part of the larger Canadian Rocky Mountain Parks World Heritage Site.

Fossils of Stanleycaris can be seen by the public in the new Burgess Shale fossil display in the Willner Madge Gallery, Dawn of Life at ROM.

Reference: “A three-eyed radiodont with fossilized neuroanatomy informs the origin of the arthropod head and segmentation” by Joseph Moysiuk and Jean-Bernard Caron, 8 July 2022, Current Biology.
DOI: 10.1016/j.cub.2022.06.027

Major research funding support came from the National Sciences and Engineering Research Council of Canada, via a Vanier Canada Graduate Scholarship to Moysiuk and a Discovery Grant (no. 341944) to Caron.

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April 20: Why this Indigenous researcher thinks we can do science differently and more… – CBC.ca

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Quirks and Quarks54:00Why this Indigenous researcher thinks we can do science differently, and more…


On this episode of Quirks & Quarks with Bob McDonald:

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This researcher wants a new particle accelerator to use before she’s dead

Quirks and Quarks9:05This researcher wants a new particle accelerator to use before she’s dead

Physicists exploring the nature of reality need ever more capable particle colliders, so they’re exploring a successor to the Large Hadron Collider in Europe. But that new machine is at least decades away. Tova Holmes, an assistant professor at the University of Tennessee, Knoxville, is one of the physicists calling for a different kind of collider that can come online before the end of her career – or her life. This device would use a particle not typically used in particle accelerators: the muon.

A 2021 CERN file photo of the Large Hadron Collider inside the 27-kilometre tunnel near Geneva, Switzerland. The proposed new particle accelerator would require an even larger tunnel, one that’s over 100 kilometres. Physicists calling for the development of a muon accelerator say it will require much less space. (Samuel Joseph Hertzog/CERN)

Is venting the best way to deal with anger? The scientist says chill out.

Quirks and Quarks6:51Is venting the best way to deal with anger? The scientist says chill out

It turns out that acting out your anger might not be the best way to get rid of it. Sophie Kjaervik, a researcher at Virginia Commonwealth University in Richmond, Va., analyzed 154 studies of the different ways to deal with anger. Her results, published in the journal Clinical Psychology Review, suggest that techniques that reduce your heart rate and calm your mind are more effective than blowing off steam.


High intensity wildfires may release toxic forms of metals

Quirks and Quarks8:37High intensity wildfires may release toxic forms of metals

Wildfire smoke might be more dangerous than you think. A recent study in the journal Nature Communications found that when wildfires pass over soils or rocks rich in a normally harmless metal called chromium, it is transformed into a toxic form. The hotter and more intense the wildfire is, the more of this metal becomes toxic. Scott Fendorf, an Earth system science professor at Stanford University, said this study shows we should factor in the type of geology wildfires pass over to provide more targeted air quality warnings about smoke risks. 

A man sitting on a balcony with the backdrop of Montreal's skyline behind him is talking on the phone while wearing two masks: one surgical one still on his face and a black one that in this photo is pulled down below his chin.
A man wears a face mask as he cycles by the skyline of Montreal, Sunday, June 25, 2023. A smog warning is in effect for Montreal and multiple regions of the province due to forest fires. (Graham Hughes/The Canadian Press)

AI might help solve the problem of runaway conspiracy theories

Quirks and Quarks7:35AI might help solve the problem of runaway conspiracy theories

Conspiracy theories seem to have multiplied in the internet era and so far, we haven’t had much luck in debunking these beliefs. The preliminary findings of a new study on PsyArXiv, a site for psychology studies that have yet to be peer-reviewed, suggests that artificial intelligence may have more success. Thomas Costello, a postdoctoral psychology researcher at MIT was the lead author on this study, and said their findings can provide a window into how to better debunk conspiracy beliefs. 

One eye takes up the entire frame and directly in the centre of their pupil, you see the reflection of the ChatGPT logo.
This illustration photograph taken with a macro lens shows The OpenAI company logo reflected in a human eye at a studio in Paris on June 6, 2023. ChatGPT is a conversational artificial intelligence software application developed by OpenAI. (Joel Saget/AFP/Getty Images)

An Indigenous scientist explores the medicine the Earth needs

Quirks and Quarks19:12An Indigenous ecologist on why we need to stop and listen to save the planet

Earth day is April 22. And Earth is not in great shape to celebrate the day. Overheated, overpopulated, overexploited – we’re not being particularly careful with our planet. We talk to Indigenous ecologist Jennifer Grenz of the University of British Columbia about her new book, which is part memoir, part prescription for the medicine our planet needs – a compound of science and traditional wisdom.  Her book is Medicine Wheel for the Planet: A journey toward personal and ecological healing.

READ MORE: An Indigenous ecologist on why we need to stop and listen to save the planet

A shot of a woman wearing big green glasses outside, looking at a tree branch.
Jennifer Grenz is an Indigenous Ecologist and author of Medicine Wheel for the Planet: A journey toward personal and ecological healing. (Paulo Ramos/UBC)

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Dragonfly: NASA greenlights most important mission of the century – Earth.com

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In a remarkable development, NASA has given the green light to the Dragonfly mission, a revolutionary rotorcraft designed to investigate the complex chemistry of Saturn‘s moon Titan.

This confirmation allows the mission to proceed with the final design, construction, and testing of the spacecraft and its scientific instruments.

Deciphering the prebiotic chemistry on Titan

The Dragonfly mission, led by Dr. Melissa Trainer of NASA’s Goddard Space Flight Center, will carry a cutting-edge instrument called the Dragonfly Mass Spectrometer (DraMS).

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This powerful tool will help scientists delve into the intricate chemistry at work on Titan, potentially shedding light on the chemical processes that led to the emergence of life on Earth, known as prebiotic chemistry.

“We want to know if the type of chemistry that could be important for early pre-biochemical systems on Earth is taking place on Titan,” explains Dr. Trainer, a planetary scientist and astrobiologist specializing in Titan.

Titan: Dragonfly’s target

Titan, the largest moon of Saturn, is shrouded in a dense nitrogen-rich atmosphere, bears a striking resemblance to Earth in many ways. With a diameter of 5,150 kilometers, Titan is the second-largest moon in our solar system, surpassed only by Jupiter’s Ganymede.

Dense atmosphere and unique climate

One of Titan’s most distinctive features is its thick atmosphere, which is composed primarily of nitrogen and methane. This dense atmosphere creates a surface pressure 1.5 times higher than Earth’s, making it the only moon in our solar system with a substantial atmosphere.

The presence of methane in Titan’s atmosphere leads to a fascinating hydrological cycle, similar to Earth’s water cycle, but with methane as the primary liquid.

Titan’s surface is dotted with numerous lakes and seas of liquid hydrocarbons, predominantly methane and ethane. These liquid bodies, some of which are larger than the Great Lakes on Earth, are the result of Titan’s unique climate and atmospheric conditions.

The Cassini mission, which explored the Saturn system from 2004 to 2017, provided stunning images and data of these extraterrestrial lakes and seas.

Dragonfly mission to search Titan for prebiotic chemistry and life

The complex chemistry occurring on Titan’s surface and in its atmosphere has drawn significant attention from astrobiologists.

With its abundant organic compounds and the presence of liquid methane, Titan is considered a prime candidate for studying prebiotic chemistry and the potential for life to emerge in environments different from Earth.

Beneath Titan’s icy crust lies another intriguing feature: a global subsurface ocean of liquid water and ammonia. This ocean, which is believed to be salty and have a high pH, may potentially host microbial life.

The presence of this subsurface ocean, along with the unique chemistry on Titan’s surface, makes this moon a fascinating target for future exploration and scientific research.

Pushing the boundaries of rotorcraft exploration

Nicky Fox, associate administrator of the Science Mission Directorate at NASA Headquarters, emphasized the significance of the Dragonfly mission, stating, “Exploring Titan will push the boundaries of what we can do with rotorcraft outside of Earth.”

Titan’s unique characteristics, including its abundant complex carbon-rich chemistry, interior ocean, and past presence of liquid water on the surface, make it an ideal destination for studying prebiotic chemical processes and the potential habitability of an extraterrestrial environment.

Innovative design and cutting-edge technology

The Dragonfly robotic rotorcraft will leverage Titan’s low gravity and dense atmosphere to fly between different points of interest on the moon’s surface, spanning several miles apart.

This innovative approach allows the entire suite of instruments to be relocated to new sites once the previous one has been thoroughly explored, providing access to samples from diverse geological environments.

DraMS, developed by the same team responsible for the Sample Analysis at Mars (SAM) instrument suite aboard the Curiosity rover, will analyze surface samples using techniques tested on Mars.

Dr. Trainer emphasized the benefits of this heritage, stating, “This design has given us an instrument that’s very flexible, that can adapt to the different types of surface samples.”

Dragonfly mission challenges and funding

The Dragonfly mission successfully passed its Preliminary Design Review in early 2023. However, due to funding constraints, the mission was asked to develop an updated budget and schedule.

The revised plan, presented and conditionally approved in November 2023, hinged on the outcome of the fiscal year 2025 budget process.

With the release of the president’s fiscal year 2025 budget request, Dragonfly is now confirmed with a total lifecycle cost of $3.35 billion and a launch date set for July 2028.

This reflects a cost increase of approximately two times the initially proposed cost and a delay of more than two years from the original selection in 2019.

Despite the challenges posed by funding constraints, the COVID-19 pandemic, supply chain issues, and an in-depth design iteration, NASA remains committed to the Dragonfly mission.

Additional funding has been provided for a heavy-lift launch vehicle to shorten the mission’s cruise phase and compensate for the delayed arrival at Titan.

Rigorous testing and validation

To ensure the success of the Dragonfly mission, researchers on Earth have conducted extensive testing and validation of the designs and models for the nuclear-powered, car-sized drone.

The mission team has carried out test campaigns at NASA’s Langley Research Center, utilizing the Subsonic Tunnel and the Transonic Dynamics Tunnel (TDT) to validate computational fluid dynamics models and gather data under simulated Titan atmospheric conditions.

Ken Hibbard, Dragonfly mission systems engineer at APL, emphasized the importance of these tests, stating, “All of these tests feed into our Dragonfly Titan simulations and performance predictions.”

As the Dragonfly mission progresses, it marks a new era of exploration and scientific discovery. Dr. Trainer expressed her excitement, saying, “Dragonfly is a spectacular science mission with broad community interest, and we are excited to take the next steps on this mission.”

Turning science fiction into fact with the Dragonfly mission

In summary, the Dragonfly mission embodies the essence of human curiosity and the relentless pursuit of knowledge. As NASA prepares to send this revolutionary rotorcraft to the alien world of Titan, we stand on the brink of a new era of exploration and discovery.

With its innovative design, cutting-edge technology, and the unwavering dedication of the mission team, Dragonfly will unlock the secrets of prebiotic chemistry and shed light on the potential for life beyond Earth.

As we eagerly await the launch of this titanic mission, we can only imagine the wonders that await us on Saturn’s enigmatic moon. The Dragonfly mission is a testament to the indomitable human spirit and our boundless capacity to push the frontiers of knowledge.

In the words of Ken Hibbard, “With Dragonfly, we’re turning science fiction into exploration fact,” and that fact will undoubtedly inspire generations to come.

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Marine plankton could act as alert in mass extinction event: UVic researcher – Langley Advance Times

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A University of Victoria micropaleontologist found that marine plankton may act as an early alert system before a mass extinction occurs.

With help from collaborators at the University of Bristol and Harvard, Andy Fraass’ newest paper in the Nature journal shows that after an analysis of fossil records showed that plankton community structures change before a mass extinction event.

“One of the major findings of the paper was how communities respond to climate events in the past depends on the previous climate,” Fraass said in a news release. “That means that we need to spend a lot more effort understanding recent communities, prior to industrialization. We need to work out what community structure looked like before human-caused climate change, and what has happened since, to do a better job at predicting what will happen in the future.”

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According to the release, the fossil record is the most complete and extensive archive of biological changes available to science and by applying advanced computational analyses to the archive, researchers were able to detail the global community structure of the oceans dating back millions of years.

A key finding of the study was that during the “early eocene climatic optimum,” a geological era with sustained high global temperatures equivalent to today’s worst case global warming scenarios, marine plankton communities moved to higher latitudes and only the most specialized plankton remained near the equator, suggesting that the tropical temperatures prevented higher amounts of biodiversity.

“Considering that three billion people live in the tropics, the lack of biodiversity at higher temperatures is not great news,” paper co-leader Adam Woodhouse said in the release.

Next, the team plans to apply similar research methods to other marine plankton groups.

Read More: Global study, UVic researcher analyze how mammals responded during pandemic

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