Paleocanna tentaculum
Jellyfish are delicate, almost ghostly creatures. But under just the right circumstances, these spectral invertebrates can still tell stories long after their death. Not far from Quebec City, Canada marine paleontologists have discovered a new species of invertebrate that swayed in Paleozoic ocean currents over 450 million years ago. Paleocanna tentaculum may not look much like its living descendants, but according to a team of researchers writing in the Journal of Paleontology, the tubular polyp is more closely related to today’s jellyfish than its other ancient cousins.
The geological record contains far more examples of vertebrate fossils than invertebrates, or animals without a backbone. Given how few invertebrate samples there are in the fossil record, the study’s authors were particularly excited to finally examine a collection of unique specimens housed at Montreal’s Musée de paléontologie et de l’évolution (MPE). The specimens were first uncovered during a 2010 dig at the Upper Neuville Formation in the Saint Lawrence Lowlands—about 31 miles northeast of Quebec’s capital. A total of 15 limestone slabs were excavated by amateur fossil hunter John Iellamo and donated to the MPE.
“He was able to recognize the scientific importance of these fossils and made them available for research. Without him, we would not be talking about this new species,” study co-author and McGill University paleontologist Louis-Philippe Bateman said in a statement.
Bateman and colleagues tallied around 135 fossilized specimens before photographing and measuring 39 examples. They then compared their anatomy to 69 living and extinct species related to present-day jellyfish. The team soon realized many of the creatures were aligned in the same direction when they died.
“We think they were buried in place, or were not transported far before being buried,” explained study co-author and Université de Montréal palebiologist Greta Ramirez-Guerrero. “This rapid burial, combined with low-oxygen conditions in the surrounding environment, slowed decay and helped preserve the animals before the sediment turned to rock.”
Unlike many jellyfish species, P. tentaculum wasn’t a free-floating organism. Instead, the tubular polyp likely anchored itself to the Paleozoic ocean floor, using its crown of tentacles to capture nearby prey. Despite its alien-like appearance, a taxonomic analysis shows the ancient creatures are much more closely related to living species like box jellies than they are to extinct, tube-dwelling animals. This places the animal much closer to present-day marine invertebrates than most other fossil polyps. Aside from its uniqueness, P. tentaculum serves as a valuable reminder that important paleontological discoveries aren’t always made in the most famous fossil formations.
“I’ve often caught myself saying that we have a less glamorous fossil record than places like British Columbia or Alberta,” said Bateman. “Discoveries like this one show that many things have yet to be discovered and described here.”
Glissements de terrain et sédimentation événementielle à Manicouagan
Slope failures and event sedimentation in Manicouagan impact crater lake, northeastern Canada: From the 1663 CE Charlevoix earthquake to the large reservoir impoundment.
Léo Chassiot and colleagues used a transect of sediment cores to unravel the environmental history of a 60-km-long fjord-type lake drowned by the impoundment of Manicouagan Reservoir, the Eye of Quebec in northeastern Canada. The sediment cores, collected between 140 m and 430 m deep, contain numerous event deposits generated from multiple landslides, some of which were related to the major 1663 Charlevoix earthquake. The records further highlight how the filling of the annular crater severely disrupted sedimentary regimes with the onset of organic-rich sediments.
Read the full article: geosociety.co/slope
Oeuf de synapside
En 150 ans de recherches paléontologiques en Afrique du Sud, on avait encore jamais découvert d'oeuf de synapside ! A tel point qu'on se demandait s'ils n'étaient pas déjà vivipares. Et pourtant....
Ce petit embryon appartient à Lystrosaurus, et la taille de l'oeuf qui le contient nous indique qu'il ne produisait pas de lait, que le petit était précoce et que ses parents devaient prendre soin de lui, ce qui a certainement contribué à la survie de cette espèce durant la crise Permien-Trias.
Life May Have Started as Sticky Goo, Long Before Cells Even Existed
Scientists have many theories about how Earth's raw materials turned into living cells, but a new proposal is particularly slimy.
In a recent paper, an international team argues that life may have first emerged within a blob of sticky goo clinging to a rock, long before true cells existed.
Similar to the bacterial biofilms we see today on rocks, pond surfaces, and even your unbrushed teeth, a semi-solid gel matrix would provide the perfect place for life to set up shop, the authors propose, both on Earth and, potentially, on other planets.
This jelly-life notion is a bit niche: Most origin-of-life theories set the scene for the first organic chemistry in water, not goo.
But those theories also struggle to explain how simple molecules of the kind that were probably floating around in Earth's waters could have transformed into something as complex as RNA (ribonucleic acid) or DNA (deoxyribonucleic acid) without some extra support.
A gel-like environment could solve several of those issues at once.
"While many theories focus on the function of biomolecules and biopolymers, our theory instead incorporates the role of gels at the origins of life," says Hiroshima University astrobiologist Tony Jia.
A gel medium, Jia and co-authors propose, would be able to trap and organize molecules into formations stable enough to overcome some key barriers in pre-life chemistry.
Early Earth was not the relatively mild, ozone-blanketed place we know today. Intense ultraviolet radiation could hit the surface unimpeded, and temperatures were extreme.
Prebiotic gels, the team suggests, could have offered much-needed protection to life's fragile chemistry, long before actual membrane-bound cells had a chance to develop.
In this theory, which was first proposed in 2005 and expanded on here, protocells were not the first step in the origin of life, but rather the outcome of the chemical organization established by the primordial goo.
"Here, we outline the prebiotic gel-first framework, which considers that early life may have emerged within surface-attached gel matrices," the researchers write.
"Such prebiotic gels may have allowed primitive chemical systems to overcome key barriers in prebiotic chemistry by enabling molecular concentration, selective retention, reaction efficiency, and environmental buffering."
In these early gels, they propose, the first murmurs of a metabolism could have arisen as chemicals traded electrons. Along with visible and infrared light, ultraviolet light penetrating the gel could have provided additional energy for chemical reactions within, much as photosynthesis does in plants today.
Gels can concentrate monomers, such as activated nucleotides and amino acids, the team adds, and are composed in a way that selectively retains and interacts with certain chemicals, not others.
The moist but not-quite-wet environment within a gel matrix favors reactions that can link monomers together to form polymers – complex molecules like those in our own bodies – as opposed to hydrolysis reactions, in which chemicals break down into smaller parts.
This broadens what we're looking for when it comes to life beyond Earth, too. Structures like gels, rather than specific chemicals, may be targets in future missions looking for life in space.
Fossilized vomit reveals 290-million-year-old predator’s diet
Two hundred and ninety million years ago, in a mountain valley within the central region of the supercontinent Pangaea, an apex predator snapped up at least three other animals and sometime later puked up the bones.
That material hardened over the ages, and is now the oldest fossilized vomit ever discovered from a land-based ecosystem. The cluster of bones and digestive material provides rare information, published January 30 in Scientific Reports, about the behavior of some of the world’s earliest land predators.
“It’s kind of like a photograph of a moment in the past that is telling us about the animal that was living,” says Arnaud Rebillard, a paleontologist at Museum für Naturkunde in Berlin. “Any data that we can find about their behavior is very precious.”
Paleontologists discovered the lime-sized specimen in 2021 at a site called the Bromacker locality in central Germany. Researchers then scanned the bones to create 3-D models showing a cluster of parts from different animals, suggesting they had come from a predator’s gut. They also chemically analyzed the material surrounding the bones and found that it was low in phosphorus, suggesting it was not a fossilized dropping.
While the specific predator that regurgitated the bones is unknown, the researchers strongly suspect that it was one of two animals that resemble today’s monitor lizards like Komodo dragons: Dimetrodon teutonis, with a prominent sail on its back, and Tambacarnifex unguifalcatus. Though reptilian in appearance, both are from a group of animals called synapsids that includes mammals and their extinct relatives.
Among the 41 disgorged bones, the researchers were able to distinguish two small lizardlike reptiles and a limb bone from a larger reptilelike herbivore. This collection of remains, along with several unidentified bones, indicates that the predator ate whatever it could find rather than specializing in a specific type of prey.
Because the fossilized vomit, or regurgitalite, contains three different animals eaten by one predator, “we can literally say, for sure, that these three animals were living at exactly the same place and exactly the same time, maybe to the week or even to the day,” Rebillard says.
Several living predators habitually regurgitate bones and other body parts that are tough to digest after eating. Scientists don’t know if this is why the ancient animal spit up the bones, but it is one of the most plausible explanations, along with simply overeating, Rebillard says.
Fossils of partially digested material, including regurgitalites, as well as fossilized feces, are valuable clues for studying Earth’s past. “We need fossils like this to really tie together how the ecosystem functioned and how the food webs were structured,” says Martin Qvarnström, a paleontologist at Uppsala University in Sweden who was not involved in the new study.
The German regurgitalite is particularly exciting because the Bromacker site preserves a snapshot of an early terrestrial ecosystem. Older predators that could travel on land often lived in semiaquatic environments where they hunted crustaceans and fish. The Permian period represents a time when large herbivores became prominent in inland environments, followed by new predators. Fossil dung and vomit are much rarer in inland environs than in aquatic ones.
“We’re talking about almost 300-million-year-old ecosystems,” Rebillard says. “So to have such a temporal vision about this to the day they were living, in the same area and the same moment, is extremely fascinating.”
Les cératopsiens d'Appalachie
Des cératopsiens, plus précisément des leptocératopsiens indéterminés, vivaient dans les Appalaches au Crétacé supérieur. Des indices suggèrent qu'ils étaient distincts des espèces de Laramidie. Un fossile clé, un maxillaire partiel (YPM-PU 24964) découvert dans la formation de Tar Heel (Campanien) en Caroline du Nord, a confirmé leur présence.
D'autres restes potentiels de cératopsiens, notamment des dents et d'éventuels fossiles de chasmosaurinés, ont été mis au jour dans la région, révélant une faune plus complexe et diversifiée qu'on ne le pensait.
Les enregistrements stratigraphique et paléontologique ordoviciens et siluriens d’Anticosti comme valeur universelle exceptionnelle (André Desrochers)
Les éponges en colonnes retrouvées à Anticosti sont des éponges fossiles appelées stromatoporoïdes, plus précisément de la famille des Aulacératidés. Elles vivaient fixées au fond d’une mer chaude et peu profonde à l’Ordovicien.
Plateosaurus (Fernando Usabiaga Bustos)
Plateosaurus was one of the earliest large-bodied dinosaurs to walk the Earth.
Living during the Late Triassic, around 216–204 million years ago, Plateosaurus thrived across what is now Europe. It belonged to the early sauropodomorphs, a group that would later give rise to the giant long-necked sauropods.
Reaching lengths of up to 10 meters, Plateosaurus was primarily herbivorous, feeding on prehistoric vegetation in forested and swampy environments. Its anatomy shows a transitional stage in dinosaur evolution, combining traits of both early bipedal dinosaurs and later massive quadrupeds.
Plateosaurus offers a rare glimpse into the early rise of dinosaurs, long before they dominated the Jurassic world.
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