First dinosaur age hagfish discovery


Tethymyxine tapirostrum, is a 100-million-year-old, 12-inch long fish embedded in a slab of Cretaceous period limestone from Lebanon, believed to be the first detailed fossil of a hagfish. Credit: Tetsuto Miyashita, University of Chicago

From the University of Chicago Medical Center in the USA:

Fossilized slime of 100-million-year-old hagfish shakes up vertebrate family tree

January 21, 2019

Paleontologists at the University of Chicago have discovered the first detailed fossil of a hagfish, the slimy, eel-like carrion feeders of the ocean. The 100-million-year-old fossil helps answer questions about when these ancient, jawless fish branched off the evolutionary tree from the lineage that gave rise to modern-day jawed vertebrates, including bony fish and humans.

The fossil, named Tethymyxine tapirostrum, is a 12-inch long fish embedded in a slab of Cretaceous period limestone from Lebanon. It fills a 100-million-year gap in the fossil record and shows that hagfish are more closely related to the blood-sucking lamprey than to other fishes. This means that both hagfish and lampreys evolved their eel-like body shape and strange feeding systems after they branched off from the rest of the vertebrate line of ancestry about 500 million years ago.

“This is a major reorganization of the family tree of all fish and their descendants. This allows us to put an evolutionary date on unique traits that set hagfish apart from all other animals,” said Tetsuto Miyashita, PhD, a Chicago Fellow in the Department of Organismal Biology and Anatomy at UChicago who led the research. The findings are published this week in the Proceedings of the National Academy of Sciences.

The slimy dead giveaway

Modern-day hagfish are known for their bizarre, nightmarish appearance and unique defense mechanism. They don’t have eyes, or jaws or teeth to bite with, but instead use a spiky tongue-like apparatus to rasp flesh off dead fish and whales at the bottom of the ocean. When harassed, they can instantly turn the water around them into a cloud of slime, clogging the gills of would-be predators.

This ability to produce slime is what gave away the Tethymyxine fossil. Miyashita used an imaging technology called synchrotron scanning at Stanford University to identify chemical traces of soft tissue that were left behind in the limestone when the hagfish fossilized. These soft tissues are rarely preserved, which is why there are so few examples of ancient hagfish relatives to study.

The scanning picked up a signal for keratin, the same material that makes up fingernails in humans. Keratin, as it turns out, is a crucial part of what makes the hagfish slime defense so effective. Hagfish have a series of glands along their bodies that produce tiny packets of tightly-coiled keratin fibers, lubricated by mucus-y goo. When these packets hit seawater, the fibers explode and trap the water within, turning everything into shark-choking slop. The fibers are so strong that when dried out they resemble silk threads; they’re even being studied as possible biosynthetic fibers to make clothes and other materials.

Miyashita and his colleagues found more than a hundred concentrations of keratin along the body of the fossil, meaning that the ancient hagfish probably evolved its slime defense when the seas included fearsome predators such as plesiosaurs and ichthyosaurs that we no longer see today.

“We now have a fossil that can push back the origin of the hagfish-like body plan by hundreds of millions of years,” Miyashita said. “Now, the next question is how this changes our view of the relationships between all these early fish lineages.”

Shaking up the vertebrate family tree

Features of the new fossil help place hagfish and their relatives on the vertebrate family tree. In the past, scientists have disagreed about where they belonged, depending on how they tackled the question. Those who rely on fossil evidence alone tend to conclude that hagfish are so primitive that they are not even vertebrates. This implies that all fishes and their vertebrate descendants had a common ancestor that — more or less — looked like a hagfish.

But those who work with genetic data argue that hagfish and lampreys are more closely related to each other. This suggests that modern hagfish and lampreys are the odd ones out in the family tree of vertebrates. In that case, the primitive appearance of hagfish and lampreys is deceptive, and the common ancestor of all vertebrates was probably something more conventionally fish-like.

Miyashita’s work reconciles these two approaches, using physical evidence of the animal’s anatomy from the fossil to come to the same conclusion as the geneticists: that the hagfish and lampreys should be grouped separately from the rest of fishes.

“In a sense, this resets the agenda of how we understand these animals,” said Michael Coates, PhD, professor of organismal biology and anatomy at UChicago and a co-author of the new study. “Now we have this important corroboration that they are a group apart. Although they’re still part of vertebrate biodiversity, we now have to look at hagfish and lampreys more carefully, and recognize their apparent primitiveness as a specialized condition.

Paleontologists have increasingly used sophisticated imaging techniques in the past few years, but Miyashita’s research is one of a handful so far to use synchrotron scanning to identify chemical elements in a fossil. While it was crucial to detect anatomical structures in the hagfish fossil, he believes it can also be a useful tool to help scientists detect paint or glue used to embellish a fossil or even outright forge a specimen. Any attempt to spice up a fossil specimen leaves chemical fingerprints that light up like holiday decorations in a synchrotron scan.

“I’m impressed with what Tetsuto has marshaled here,” Coates said. “He’s maxed out all the different techniques and approaches that can be applied to this fossil to extract information from it, to understand it and to check it thoroughly.”

The hagfish dates back at least 300 million years. The secret of survival for these eel-like sea creatures can be found in the rate and volume of slime it produces to fend off predators. Interestingly, the oldest fossils of these eel-like sea creatures, were found in Illinois, and today researchers from the University of Illinois at Urbana-Champaign are beginning to uncover the mystery of how the hagfish uses this substance to choke its predators: here.

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Dinosaur age shark discovery


One of the tiny fossilized teeth recovered from Galagadon, so named for the shape of its teeth, which resemble the spaceships in the video game Galaga. Credit: Copyright Terry Gates

From North Carolina State University in the USA:

Ancient carpet shark discovered with ‘spaceship-shaped’ teeth

January 21, 2019

The world of the dinosaurs just got a bit more bizarre with a newly discovered species of freshwater shark whose tiny teeth resemble the alien ships from the popular 1980s video game Galaga.

Unlike its gargantuan cousin the megalodon, Galagadon nordquistae was a small shark (approximately 12 to 18 inches long), related to modern-day carpet sharks such as the “whiskered” wobbegong. Galagadon once swam in the Cretaceous rivers of what is now South Dakota, and its remains were uncovered beside “Sue”, the world’s most famous T. rex fossil.

“The more we discover about the Cretaceous period just before the non-bird dinosaurs went extinct, the more fantastic that world becomes,” says Terry Gates, lecturer at North Carolina State University and research affiliate with the North Carolina Museum of Natural Sciences. Gates is lead author of a paper describing the new species along with colleagues Eric Gorscak and Peter J. Makovicky of the Field Museum of Natural History.

“It may seem odd today, but about 67 million years ago, what is now South Dakota was covered in forests, swamps and winding rivers,” Gates says. “Galagadon was not swooping in to prey on T. rex, Triceratops, or any other dinosaurs that happened into its streams. This shark had teeth that were good for catching small fish or crushing snails and crawdads.”

The tiny teeth — each one measuring less than a millimeter across — were discovered in the sediment left behind when paleontologists at the Field Museum uncovered the bones of “Sue”, currently the most complete T. rex specimen ever described. Gates sifted through the almost two tons of dirt with the help of volunteer Karen Nordquist, whom the species name, nordquistae, honors. Together, the pair recovered over two dozen teeth belonging to the new shark species.

“It amazes me that we can find microscopic shark teeth sitting right beside the bones of the largest predators of all time,” Gates says. “These teeth are the size of a sand grain. Without a microscope you’d just throw them away.”

Despite its diminutive size, Gates sees the discovery of Galagadon as an important addition to the fossil record. “Every species in an ecosystem plays a supporting role, keeping the whole network together,” he says. “There is no way for us to understand what changed in the ecosystem during the mass extinction at the end of the Cretaceous without knowing all the wonderful species that existed before.”

Gates credits the idea for Galagadon’s name to middle school teacher Nate Bourne, who worked alongside Gates in paleontologist Lindsay Zanno’s lab at the N.C. Museum of Natural Sciences.

Martin Luther King 1964 speech rediscovered


This 21 January 2019 video from the USA says about itself:

MLK Day Special: Rediscovered 1964 King Speech on Civil Rights, Segregation & Apartheid South Africa

In a Democracy Now! and Pacifica Radio Archives exclusive, we air a newly discovered recording of Dr. Martin Luther King Jr. On December 7, 1964, days before he received the Nobel Peace Prize in Oslo, King gave a major address in London on segregation, the fight for civil rights and his support for Nelson Mandela and the anti-apartheid struggle in South Africa. The speech was recorded by Saul Bernstein, who was working as the European correspondent for Pacifica Radio. Bernstein’s recording was recently discovered by Brian DeShazor, director of the Pacifica Radio Archives.

Japanese man marries robot girl


This 21 December 2013 punk rock music video from Scotland says about itself:

The Valves – Robot Love

Live at Edinburgh Liquid Rooms

The Scottish band The Valves wrote this song much earlier, in 1977.

However, now something happens not in song lyrics, but in reality.

From the New York Times, 19 January 2019:

Do You Take This Robot …

When Akihiko Kondo, a 35-year-old school administrator in Tokyo, strolled down the aisle in a white tuxedo in November, his mother was not among the 40 well-wishers in attendance. For her, he said, “it was not something to celebrate.”

You might see why. The bride, a songstress with aquamarine twin tails named Hatsune Miku, is not only a world-famous recording artist who fills up arenas throughout Japan: She is also a hologram.

Mr. Kondo insists the wedding was not a stunt, but a triumph of true love after years of feeling ostracized by real-life women for being an anime otaku, or geek.

New snake species discovery in other snake’s stomach


This 26 December 2018 French language video is about a new snake species, Cenaspis aenigma, discovered in another snake’s stomach.

From the University of Texas at Arlington in the USA:

New species of snake found in stomach of predator snake

January 19, 2019

Herpetologists at The University of Texas at Arlington have described a previously unknown species of snake that was discovered inside the stomach of another snake more than four decades ago.

The new snake has been named Cenaspis aenigma, which translates from Latin as “mysterious dinner snake”. It is described in a recent paper in the Journal of Herpetology titled “Caudals and Calyces: The Curious Case of a Consumed Chiapan Colubroid.” The paper was co-authored by Jonathan Campbell, UTA professor of biology; Eric Smith, UTA associate professor of biology; and Alexander Hall, who earned a UTA doctorate in quantitative biology in 2016.

The researchers’ work identifies Cenaspis as not only a new species but also an entirely new genus.

The specimen was found in the stomach of a Central American coral snake — a species that has been known to eat smaller snakes — by palm harvesters in the southern Mexico state of Chiapas in 1976. The 10-inch long specimen was preserved in a museum collection. Amazingly, a live specimen has never been found in the ensuing 42 years.

“This small snake was obtained now over 40 years ago, and the report of its discovery has been a long time in coming”, the co-authors wrote in the Journal of Herpetology paper. “We were optimistic that additional specimens might be secured, but after at least a dozen more trips into the region spanning several decades, we have been unrewarded.”

Cenaspis has several unique features that defy placing it in any known genus and clearly distinguishes it from all known genera. These include undivided subcaudal scales, or enlarged plates on the underside of its tail; a lack of spines and presence of cup-like structures called calyces on its hemipenes, or paired male reproductive organs found in snakes and lizards; and the shape of its skull.

The first two of those features are not found in any other known snake in the family Colubridae in the Western Hemisphere. Colubridae is the largest snake family and includes just over 51 percent of all known living snake species.

Utilizing the vast resources of UTA’s Amphibian and Reptile Diversity Research Center for comparative purposes, the researchers made CT scans of dozens of specimens of snakes. The biologists believe that due to some of the specimen’s physical features, Cenaspis is likely a burrowing snake that feeds on insects and spiders. Campbell believes that Cenaspis is not extinct but has eluded capture due to its burrowing lifestyle and other elusive habits.

“This provides evidence of just how secretive some snakes can be”, Campbell told National Geographic, which ran a story about the discovery in its Dec, 19, 2018, edition. “Combine their elusive habits with restricted ranges and some snakes do not turn up often.”

He noted said that because of the snake’s unique nature, the Chiapas highlands area of southern Mexico where it was found all those years ago should be considered for protected status, so that more unknown species can be discovered and not face possible extinction.