Mammal-like reptiles, warm-blooded earlier than thought


This video says about itself:

19 May 2016

Ophiacodon (meaning “snake tooth”) is an extinct genus of synapsids belonging to the family Ophiacodontidae that lived from the Late Carboniferous to the Early Permian in North America and possibly Europe. The genus was named along with its type species O. mirus by paleontologist Othniel Charles Marsh in 1878 and currently includes five other species. As an ophiacodontid, Ophiacodon is one of the most basal synapsids and is close to the evolutionary line leading to mammals.

Music: Pianoman by Billy Joel.

From the University of Bonn in Germany:

Warm-bloodedness possibly much older than previously thought

Characteristic may have developed 20 million years earlier, study shows

May 18, 2017

Summary: Warm-bloodedness in land animals could have evolved much earlier than previously thought, suggests a study of the bones of the long-extinct mammal predecessor Ophiacodon.

Warm-bloodedness in land animals could have developed in evolution much earlier than previously thought. This is shown by a recent study at the University of Bonn, which has now been published in the journal Comptes Rendus Palevol.

People who like watching lizards often get the best opportunity to do so in the morning, as they can usually be found sunbathing at this time of day. This is because they rely on an external energy supply to reach their operating temperature. However, mice and other mammals make themselves nice and cozy in a different way: they burn calories and can even keep themselves warm during a bitterly cold winter’s night.

Mammals are thus referred to as warm-blooded. Until now, it was thought that the “body heater” was invented in four-legged land animals around 270 million years ago. “However, our results indicate that warm-bloodedness could have been created 20 to 30 million years earlier,” explains Prof. Martin Sander from the Steinmann Institute for Geology, Mineralogy and Paleontology at the University of Bonn.

Bones as a thermometer

For long-extinct animals, it is naturally not possible to simply determine body temperature using a thermometer. However, warm-bloodedness leaves behind tell-tale signs in fossils. It not only means that the animal is not reliant on the ambient temperature, but also enables faster growth. “And this is shown in the structure of the bones,” explains Sander.

Bones are composites of protein fibers, collagen, and a biomaterial, hydroxyapatite. The more orderly the arrangement of the collagen fibers, the more stable the bone, but the more slowly it normally grows as well. The bones of mammals thus have a special structure. This allows them to grow quickly and yet remain stable. “We call this bone form fibrolamellar,” says the paleontologist.

Together with his PhD student Christen D. Shelton (now at the University of Cape Town), the scientist looked at humerus bones and femurs from a long-extinct land animal: the mammal predecessor Ophiacodon. This lived 300 million years ago. “Even in Ophiacodon, the bones grew as fibrolamellar bones,” says Sander to summarize the analysis results. “This indicates that the animal could already have been warm-blooded.”

Ophiacodon was up to two meters long, but otherwise resembled today’s lizards — and not without good reason: mammals and reptiles are related; they thus share a predecessor. In the family tree, Ophiacodon is very close to the place where these two branches separate.

Were the first reptiles warm-blooded?

However, lizards, turtles and other reptiles living today are cold-blooded. Until now, it has been assumed that this was the original form of the metabolism — i.e. that the shared ancestor of both animal groups was cold-blooded. Warm-bloodedness would thus be a further development, which arose over the course of mammalian evolution.

However, Ophiacodon appears a very short time after the division between mammals and reptiles. “This raises the question of whether its warm-bloodedness was actually a completely new development or whether even the very first land animals before the separation of both branches were warm-blooded,” says Sander. That is just speculation. However, if this theory is correct, we would have to drastically correct our image: the first reptiles would then also have been warm-blooded — and would have only discarded this type of metabolism later.

Green turtle video


This video says about itself:

Green Turtle‘s Battle For Survival – Planet Earth – BBC Earth

From the moment they are born, these plucky Green Turtles from Ascension Island will face a huge battle to survive. Those that do survive, like their mothers did before them, will return to exactly same beach where they hatched.

Fossil snake discovery in Tennessee, USA


Zilantophis schuberti is a newly identified snake species found in eastern Tennessee. This small creature lived roughly 5 million years ago. Credit: Image by Steven Jasinski

From the University of Pennsylvania in the USA:

Fossil ‘winged serpent‘ is a new species of ancient snake

May 12, 2017

Summary: An ancient sink hole in eastern Tennessee holds the clues to an important transitional time in the evolutionary history of snakes. Among the fossilized creatures found there, according to a new paper, is a new species of snake that lived 5 million years ago.

An ancient sink hole in eastern Tennessee holds the clues to an important transitional time in the evolutionary history of snakes. Among the fossilized creatures found there, according to a new paper co-authored by a University of Pennsylvania paleontologist, is a new species of snake that lived 5 million years ago.

Steven Jasinski, lead author of the new study, is a doctoral student in Penn’s Department of Earth and Environmental Science in the School of Arts & Sciences and acting curator of paleontology and geology at the State Museum of Pennsylvania. He is completing his Ph.D. under Peter Dodson, a professor of paleontology in Arts & Sciences and professor of anatomy in the School of Veterinary Medicine at Penn.

The fossils come from the Gray Fossil Site near East Tennessee State University, where Jasinski and co-author David Moscato pursued their master’s degrees.

This study, published in the Journal of Herpetology, involved many hours of close examination of hundreds of dark mineral-stained snake fossils. In the end, the biggest surprise was the discovery of vertebrae that don’t match any known species of snake, living or extinct. The researchers named the new genus and species Zilantophis schuberti.

Snakes don’t have arms or legs, but they have high numbers of vertebrae,” Jasinski said. “These are often the bones that paleontologists use to identify fossil snakes.”

Zilantophis bore uniquely broad wing-shaped projections on the sides of its vertebrae. In life, these were likely attachment sites for back muscles. These features are what inspired the name of the new genus, derived from Zilant, a winged serpent in Russian mythology.

The species name, schuberti, honors Blaine Schubert, executive director of East Tenneessee State’s Don Sundquist Center of Excellence in Paleontology and advisor to both authors during their studies there. The name roughly translates to “Schubert’s Winged Snake” or “Schubert’s Winged Serpent.”

Zilantophis was a small snake, about 12-16 inches long.

“It’s about as large around as your pointer finger,” said Jasinski. “This animal was probably living in leaf litter, maybe doing a bit of digging and either eating small fish or more likely insects. It was too small to be eating a normal-sized rodent.”

“These snake vertebrae are tiny,” Moscato said. “Before we can study them, they have to be meticulously separated from the sediment and other bones. This work is done by dedicated museum workers, students and volunteers.”

Based on features of its vertebrae, this new species is thought to be most closely related to rat snakes (Pantherophis) and king snakes (Lampropeltis), both of which are relatively common in North America today.

The Gray Fossil Site is one of the richest fossil localities in the United States, particularly from the Neogene period, which spans from 23 million to 2.58 million years ago. Based on the extinct species found there, researchers estimate it to be between 7 and 4.5 million years old, straddling the boundary between the Miocene (23 to 5.33 million years ago) and Pliocene (5.33 to 2.58 million years ago) epochs. It is one of the only sites of this age in the entire eastern U.S., making it an important window into a poorly-known part of prehistory.

At the time that Zilantophis dwelled there, the site was a sinkhole surrounded by forest, attracting a variety of animals. The local fauna included ancient representatives of familiar North American creatures such as bears, beavers and salamanders. Others were more exotic, including unique species of rhinoceros, alligator and the site’s famous red panda.

“This is a time when the world was moving in the direction of a modern climate and modern fauna,” Jasinski said.

The snakes, too, were a mix of familiar and strange. In addition to the new species, there were ancient species of garter snake (Thamnophis), water snake (Nerodia), rat snake (Pantherophis), pine snake (Pituophis) and whip snake (Masticophis), among others. In total, the researchers identified seven different snake genera at the site, many of which are still found in east Tennessee today.

“Back in its day, the Gray Fossil Site was a great environment for living animals to thrive and for dead animals to fossilize,” Moscato said. “This makes for a paleontology goldmine, positively packed with bones.”

This is the first survey of snakes at this fossil site, and it focused specifically on identifying snakes of the family Colubridae, the largest snake family, which includes about two-thirds of all known living snake species.

“The Miocene was a time when the snake fauna of North America was undergoing significant changes,” Jasinski said.

In earlier times, boas, a group known for their robust vertebrae, were widespread and common across northern ecosystems, but as time went on the boas gradually retreated while colubrids, typically smaller than boas, took over. This shift coincided with continent-wide environmental change, including the replacement of forests with grasslands and the spread of small mammals that may have provided a food supply that fueled the expansion of colubrids.

“Zilantophis is part of this period of change,” Jasinski said. “It helps show that colubrids were diversifying at this time, including forms that did not make it to the present day.”

The find and continued investigations in this site help fill in details about the rich biodiversity of an ancient ecosystem as it underwent a shift in climate — details that can inform our understanding of the future as well.

“Snakes are important parts of their ecosystems, both today and in the past,” Jasinski said. “Every fossil helps tell a story, and all those pieces of evidence give scientists a clearer picture of the past, as well as tools to predict how living communities may respond to changes in the future.”

Dinosaur with skin, guts content intact


This video from Canada says about itself:

Discovery of Ankylosaur at Suncor’s Millennium Mine

On March 21, 2011 a shovel operator in Suncor’s Millennium Mine discovered an important piece of Alberta‘s history when he uncovered a dinosaur fossil.

By Nina Golgowski:

05/14/2017 03:38 pm ET

Canada Unveils ‘Dinosaur Mummy’ Found With Skin And Gut Contents Intact

“We don’t just have a skeleton. We have a dinosaur as it would have been.”

After 110-million years encased in stone, an impeccably preserved, dragon-like dinosaur has been unveiled by paleontologists in Canada and it’s unlike anything they’ve seen before.

The remains of an armor-plated nodosaur, a 3,000-pound plant-eating horned creature, went on display in Alberta on Friday after its accidental discovery by miners nearly six years ago, National Geographic reported.

“We don’t just have a skeleton,” Caleb Brown, a postdoctoral researcher at the Royal Tyrrell Museum of Paleontology where the fossil went on display, told the magazine. “We have a dinosaur as it would have been.”

Researchers say the fossil is remarkable, with it being a never-before-seen species of nodosaur, as well as the oldest dinosaur ever found in Alberta. It’s preserved skin and gut contents are also providing invaluable clues on these extinct creatures.

“I’ve been calling this one the Rosetta Stone for armor,” Donald Henderson, curator of dinosaurs at the Royal Tyrrell Museum, told National Geographic.

“It’s basically a dinosaur mummy ― it really is exceptional,” Don Brinkman, director of preservation and research, also told The New York Times.

For the last five years, researchers have spent more than 7,000 hours chiseling away at the fossil’s surrounding rock to expose the incredible creature.

The researchers have had their share of ups and downs, with the fossil breaking into pieces upon its removal from Alberta’s Millennium Mine in 2011.

The 15,000-pound, plaster-covered block it was encased in is seen shattering during a video uploaded to YouTube by Suncor Energy [see top of thuis blog post], which owns the mine.

“One of the good things about this, believe it or not, is because it’s in smaller pieces it will make preparation go a little faster,” Darren Tanke, a paleo technician with the Royal Tyrrell Museum, says in the video.

“This is restorable. Everything broke cleanly and in big pieces,” he adds. “It’s unfortunate that this happened but this is restorable.”

Adder males and females, video


This 11 May 2017 video shows male and female adders.

Males are usually greyish, with a black stripe on their back. Females are usually brownish, with a dark brown stripe on their back

Andries Ophof from the Netherlands made this video.

Biggest ever oviraptor-like dinosaur discovery in China


This video says about itself:

Oviraptorid fights to protect nest – Planet Dinosaur – BBC

26 July 2013

A female Oviraptorid guards her nest from attackers large and small, but can do nothing about the threat of nature itself.

Narrated by John Hurt, Planet Dinosaur tells the stories of the biggest, deadliest and weirdest creatures ever to walk the Earth, using the latest fossil evidence and immersive computer graphics.

From Sci-news.com:

Beibeilong sinensis: Paleontologists Identify New Species of Cassowary-Like Dinosaur

May 10, 2017 by News Staff

A team of paleontologists from Canada, China, the United States and Slovak Republic has identified a partial clutch of large dinosaur eggs with a closely associated baby dinosaur skeleton as an embryo and eggs of a new, large caenagnathid oviraptorosaur, Beibeilong sinensis.

Beibeilong sinensis (meaning ‘baby dragon from China’) lived in what is now central-eastern China during the Late Cretaceous, about 90 million years ago.

It is described by the paleontologists based on dinosaur eggs and an associated embryo that were collected in China’s Henan Province in 1993.

The unprepared specimen was imported into the United States in mid-1993 by the Stone Company, which exposed the embryo and eggs during preparation.

The specimen was featured in a cover article for National Geographic Magazine, and the embryo became popularly known as ‘Baby Louie’ in recognition of Louis Psihoyos, the photographer for the article.

“This particular fossil was outside the country for over two decades and its return to China finally allowed us to properly study the specimen and name a new dinosaur species,” said team member Prof. Lü Junchang, a paleontologist at the Institute of Geology, Chinese Academy of Geological Sciences, and lead co-author of a report published this week on Beibeilong sinensis in the journal Nature Communications.

Along with the dinosaur embryo, the Baby Louie fossil contains between six and eight very large eggs.

These eggs were given their own scientific name, Macroelongatoolithus xixiaensis (meaning ‘large elongate stone eggs’).

“The eggs are up to 18 inches (45 cm) long and weighed about 5 kg, making them some of the largest dinosaur eggs ever discovered,” the researchers said.

“They were found in a ring-shaped clutch, which was part of a nest that was about 6.5-10 feet (2-3 m) in diameter and probably contained two dozen or more eggs.”

Lead co-author Darla Zelenitsky, a professor at the University of Calgary, and her colleagues Philip Currie and Kenneth Carpenter first began examining the Baby Louie fossil shortly after it arrived in the United States.

They noticed the eggs and embryo skeleton looked similar to those of oviraptorosaurs, a group of meat-eating dinosaurs that superficially look like cassowaries, but the eggs were far too large to have been laid by any known species of such dinosaurs at the time.

“Although the identity of the dinosaur embryo could not be determined due to its state of preservation, I had recognized that the large eggs in the nest belonged to an oviraptorosaur, based on various characteristics of the eggshell,” Prof. Zelenitsky said.

“This meant that Baby Louie’s parents must have been truly gigantic, far larger than any known oviraptorosaur species at the time.”

“Dinosaur embryos, because they are so small and are only present for a short time interval in the egg, are very rarely preserved as fossils. So discovering a fossilized dinosaur embryo is equivalent to winning the lottery,” Prof. Zelenitsky noted.

“Baby Louie is the only embryo of a giant oviraptorosaur known in the world,” she said.

Ring-shaped nests of eggs of smaller oviraptorosaur species have been found with the adults sitting in the centre of the nest, so an adult Beibeilong sinensis probably shared similar behaviors.

With their parrot-like skulls, feathers, and two-legged stance, Beibeilong sinensis, weighing in at around 3 tons, are the largest dinosaurs likely to have sat on their nests to brood their clutch of eggs.

See also here.