A Water Bear In Amber

Today’s article is about [water bears]! What in the world is a water bear?? They are incredible, tiny creatures that are closely related to arthropods (animals like insects and spiders). They have other charming names like ‘moss piglets’ and more officially, tardigrades. These little animals are both adorable and amazing. They are able to survive in the most extreme conditions, like the vacuum of space, and intense radiation. And look how cute they are!

Here’s one swimming.

They were even featured in the TV show Octonauts.

A clip from The Octonauts.

This week, a new species was published that was found in a piece of amber from the Miocene (~23-5 million years ago) of the Dominican Republic. Amber is fossilized tree sap. When the sap is liquid, it drips from the trees and small organisms (like insects, pollen, and occasionally small birds and lizards) get trapped in it. When the sap hardens, it can turn into amber and anything trapped inside becomes a fossil. The authors were examining the ants trapped in this piece of amber for months before they discovered the tiny water bear. It is only one of a handful of tardigrade fossils.

Figure 1 from the article showing the water bear from the side.

The authors named this one Paradoryphoribius chronocaribbeus. They ran an analysis of evolutionary relationships to figure out what genus this little fossil belonged in. Because of its unique features, they realized that even though it belonged to a recognized group, it was a new species. So they named it ‘chrono’ meaning ‘time’ for the fossil’s age, and ‘caribbeus’ for where it was discovered.

Artist rendition of the water bear (by Holly Sullivan, Figure 6c from the paper).

Let’s hope we find more!

Dinosaur DNA!

Last week, a very exciting [paper] was published. Not only did this study show individual cells in a fossil from the Early Cretaceous (133-120 million years ago), but those individual cells show DNA preserved inside!

On the left is the specimen of Caudipteryx, showing the location of the sample in yellow (from Figure 1 of the paper). A reconstruction of Caudipteryx is on the right (art by Matt Martyniuk).

The fossil in question is a specimen of Caudipteryx, an oviraptorosaurid from the famous Jehol Biota of China. The Jehol Biota comes from a site of exquisite fossil preservation. Many of the specimens that come from there are at least partially complete (the bones are still placed how they would have been in life, or “articulated”).

The authors took a sample from the articular cartilage of the right femur (upper leg bone). Articular cartilage is a layer of softer-than-bone material that protects the ends of the bones from rubbing together where they come together in a joint, like the knee. They divided their sample into 3 sections and used different high-resolution imaging techniques and staining methods to look at the microscopic details inside.

The most impressive result was from their second section. They first dissolved all of the bony material leaving only the softer cartilage behind. Then they cut the piece into thin sections that light can pass through, and stained them. The stain fuses with cell membranes, DNA, and all of the stuff outside of the cell (“extracellular matrix”) in different colors. They did the same thing with a similar piece of a modern chicken bone for comparison.

Photos of the second piece of bone after the staining process. The purple circles are the chondrocytes and the pink central circle is the nucleus. The dark threads inside the nucleus are chromatin. On the left is the fossil, on the right is the chicken. (Figure 4c-f of the article).

They found well-preserved ‘chondrocytes’ (the cells that make cartilage), with nuclei inside. The nucleus in a cell is what holds the DNA. Inside the nucleus was darker material, in strands, which the authors describe as chromatin – a form of DNA that’s more condensed than the typical stretched out double helix. They found DNA inside of a dinosaur fossil from ~130 million years ago!

The authors do make it clear that it is unlikely that we will find DNA sequences inside a fossil of this age. The sequences are what make up the instructions for building organisms. So for right now, we (thankfully!) can’t recreate Jurassic Park. But this study shows us that with new imaging techniques, we can learn even more about these ancient organisms.

Caves and Tools

In Morocco (Africa) 120,000 years ago, a wildcat, a jackal, and a fox met in a cave. What were they doing there? And what do humans have to do with it?

Today’s post is about [human culture]. And fossils. Most of what I post here is about what fossils can tell us about how, when, and where an animal lived. Fossils can tell us so much about the biology of now extinct animals. But that’s not all they can tell us. In some cases, the bones record what happened after the animal died.

The cave location in Morocco, Africa. (Figure 1b from the paper)

The Contrebandiers Cave in Morocco has sediment layers inside that date back to 120,000 years ago. Caves make excellent shelters, so as animals and plants use the shelter or get trapped there, they are fossilized and can be discovered later. Within the Contrebandiers Cave, explorers found the fossilized bones of a golden jackal, sand fox, wildcat, and several cow-like animals.

Some of the animals found at the cave. (Attributions on the image, retrieved from Wikipedia)

But these animals were not just hanging out together, they had been brought there by the humans (Homo sapiens) that lived there at the time. According to the markings on their bones, the animals they hunted and brought back to the cave were skinned in order to make clothing. Clothing itself does not fossilize easily because the fur it was made from breaks down very quickly.

An example of how ‘spatulate’ scraping tools were made and how they were used. (Figure 4 from the paper)

The animal bones weren’t the only evidence of skinning. There were tools present in the cave as well. Tools made from animal bones and shaped in specific ways by ancient human hands. Humans today still use similar tools and methods for skinning, so we don’t have to guess what the tools were for. This cave preserves the oldest evidence of formal bone tools and the production of clothing by modern humans (Homo sapiens)in Africa.

Side note: This is the first scientific paper I’ve read that has an “Inclusion and Diversity” statement at the end. The authors state, among other important points, that they ‘actively worked to promote gender balance in our reference list.’ I am grateful that the journal includes that statement and for the author’s work.

Apex Predators Don’t Like to Share

It’s been a long time, friends. I have reached a point where I believe I can dedicate time to this wonderful space again. I’d like to start off with a paper published in August of 2021 about a new carcharodontosaurian dinosaur from Uzbekistan.

A map showing Uzbekistan, outlined in red, and the fossil site as a red dot.

 Carcharodontosaurs (kar-karo-DONT-o-soars) were large bodied meat-eating dinosaurs that roamed from the Late Jurassic (around 150 million years ago) to the early Late Cretaceous (around 90 million years ago). After that, carcharodontosaurs seem to fade away and others rule instead. We’ll come back to why that happens in a bit.

This new specimen of carcharodontosaur is named Ulughbegsaurus uzbekistanensis. The ‘Ulughbeg’ part of the name comes from the fifteenth century Uzbekistani astronomer Ulugh Beg, and ‘uzbekistanensis’ to indicate the country of discovery. The only piece of the dinosaur they found is a part of the maxilla, the part of the upper jaw that holds teeth.

The partial maxilla of Ulughbegsaurus uzbekistanensis (Figure 1 from the paper).

The authors ran a computer analysis to find out what kind of dinosaur this bone belonged to based on characteristics of the bones. The analysis was run in two different ways and both agreed that it matches more closely to carcharodontosaur dinosaurs than to others.

This discovery is from a place and time that we did not have this group of dinosaurs, but more importantly is the size of the jaw piece in comparison with other predatory dinosaurs of that area. The length of the maxilla can tell you the length of the femur (the upper bone of the leg) because the two bones grow in related ways. The length of the femur can give you an estimate of the body size. This jaw tells us that the dinosaur was over 7 meters (21 feet) long and weighed over 1000 kgs (2200 pounds).

When the largest carcharodontosaurs existed, the other predators that lived alongside them were smaller. While they existed, carcharodontosaurs occupied the apex (highest point) on the food web and other larger bodied carnivores could not compete. Once the carcharodontosaurs vanished, it gave other predators a chance to fill their ‘niche’ (a niche is a role in the environment). It was only after their disappearance that tyrannosaurs became the giants Tyrannosaurus rex in North America and Tarbasaurus baatar in Asia. After the carchardontosaur extinction in South America, the abelisaurids took over. The environment only ever has space for a few giant predators.

A New Bird from New Zealand

Last week, a [paper] was published that described a new species of bird from New Zealand. New Zealand is an island nation in the Southern hemisphere, near Australia:

A map of New Zealand, with a star showing where the fossil was discovered. From Google.

New Zealand doesn’t have a huge fossil record, especially of birds, so this new discovery is exciting for several reasons. It adds to the record of bird fossils in the Southern hemisphere and in New Zealand, and comes right after the announcement of a discovery of a giant parrot from the same nation. This bird, however, is from a line of extinct birds called the Pelagornithids.

Protodontopteryx ruthae, the new species of pelagornithid. Made by Derek Only/Canterbury Museum.

These birds are known for having little ‘tooth-like’ pegs on their beaks. These are not teeth, however, just part of the edge of beak, hence how they got their name ‘pseudoteeth’ (=’false teeth’). They range in size from wingspans of 3 meters to 5-6 meters and were some of the largest birds to be able to fly. Their size restricted them to fly only in places with lots of wind, on which they would mostly glide.

The new species, Protodontopteryx ruthae, was smaller than all the others, with a wingspan of 1 meter. This smaller size indicates that this species may have been able to fly more actively than its larger relatives. In addition to the wings, the authors also describe the skull, hips, vertebrae, and the bones that connect the arms to the body, called the pectoral girdle.

The specimen of Protodontopteryx, photo on the left, CT image on the right. From Figure 1 of the paper.

Protodontopteryx is important for a few other reasons. Since it has pseudoteeth on its beak, it shows that those pegs evolved before the adaptations for gliding. It was found in sediments that are older than the locations for the other pelagornithids, and an analysis of evolutionary relationships indicated that it is a more basal (or earlier) member of the group. These two facts tell us that Protodontopteryxis the oldest and evolutionary earliest pelagornithid that we know, in addition to being the smallest. Let’s hope we find more amazing bird fossils in New Zealand!

Archosaur Air Conditioning

Today on DrNeurosaurus I want to talk about a [study] that came out in July of this year, but has recently been going around the media. This isn’t the typical study I talk about where some new fossil is discovered and described and celebrated for its novelty (new-ness) and scientific value. This is a different kind of study.

The authors wanted to take a closer look at a structure in the head of many archosaurs. You might remember archosaurs from other posts – they’re a group of animals that include the living crocodylians and birds, their ancestor, and all of its descendants:

This tree is modified from the one found [here], on Archosaur Musings.

All of these animals have openings in the top of the skull, that previous scientists thought were home to jaw muscles. The authors looked at these openings in over 100 specimens of lizards, turtles, crocodylians, and birds using CT, MRI, dissection, and other methods.

A crocodylian skull with the openings labeled. in the top of the skull. Source unknown.

They found that in many cases, the openings didn’t have muscles all the way through. Instead, the openings contained blood vessels just under the skin. When the authors looked at extinct animals like non-avian dinosaurs and extinct crocodylians, they did not find any evidence of muscles in those locations. Using comparison to living animals, they suggest that these openings housed blood vessels instead. But for what purpose?

Well, that depends on the animal. In animals with display structures like frills, those blood vessels could provide nutrients to the structure. 

A Triceratops. Its frill is a display structure – a structure that is used to communicate with other members of its species. From the Natural History Museum, London.

In animals without those structures, the blood vessels would act as a way to regulate their body temperature. To test this, the authors used thermal imaging cameras to take photos of living crocodylians. They found that those openings were cooler than the body in hot temperatures, and hotter than the body in cool temperatures. This suggests that their hypothesis (idea) has support!

Figure 11 from the paper: an artist rendition of thermal images of Daspletosaurus, Deinonychus, and two croc-line archosaurs. By Brian Engh.

Using lots of specimens and imaging methods, the authors were able to discover something completely new about animals we’ve known for a long time, including ones living today!

Opal, Ornithopods, and Australia

In early June, a discovery was published that made me say ‘Oh, cool!’ out loud. To be fair, a lot of things make me say that, but this discovery was rare.

In New South Wales, Australia, the bones of a new species of ornithopod (duckbill) dinosaur were unearthed in an opal mine. 

Map of Australia showing where the Shipyard Opal Fields are. From Google Maps.

The dinosaur is now called Fostoria dhimbangunmal(pronounced: fos-TO-ria dim-ban-GOON-mal) after Robert Foster who discovered the bone bed, and after the words for “sheep yard” for the Sheepyard opal fields where the bone bed is located. The words for sheep yard come from the language of the Yuwaalaraay, Yuwaalayaay, and Gamilaraay peoples, who are native peoples from Australia. 

Australia does not have a large fossil record of dinosaurs, so the discovery of Fostoriais important towards understanding what the continent was like in the Mesozoic. The description of the new dinosaur comes from potentially 4 individuals – they found four shoulder blades, three of which were right shoulders, which means there were at least 3 different animals there. Besides the shoulder blades, they found many elements of the arms, legs, vertebral column, and skull. And here’s the part that made me say “Oh, cool!”: the bones are preserved in opal! Opal is known for being a gemstone and is actually the national gemstone of Australia. In the case of these dinosaur bones, it’s a shade of blue, but it can come in a variety of colors.

Photo of one of the bones of Fostoria, preserved in opal. You can see a bit of translucent blue at the top. Photo by Robert A. Smith, Australian Opal Centre.

The bones that were found are all different sizes, representing animals of different ages that were living together. This is the first discovery of a dinosaur herd from Australia! And it’s preserved in opal! How neat is that?

A Young Paleontologist Goes Viral

Hello! It’s been a long year since you heard from me. Since you heard from me last, I moved to a new city (Boston!), had a baby (who now turned 1 year old), started a new job (Suffolk University!), bought a house (#adulting) and moved again. I’m finally able to make time for DrNeurosaurus again, so hopefully I still have some readers out there.

We’ve missed a lot of great news in the past year:

  • Baby pterosaurus, or [‘flaplings’] were probably able to fly
  • [Feathers] evolved way earlier than we had imagined
  • The head of a [wolf] was found in Siberia dating to 30,000 years ago, and it almost looks like it could be sleeping
  • A new bat-winged dinosaur: [Ambopteryx]
  • And many more!

Sadly I don’t have the time to review all of these, so instead today we’re going to talk about a young paleontologist from India.

Aswatha with a fossil. From The Better India (linked below)

She recently went viral on social media as the youngest paleontologist from India, so you may have heard of her. Her name is Aswatha Biju and she’s just 12 years old. At 5 years old, she saw a picture of an ammonite in an encyclopedia and her interest in paleontology took off. Her parents brought her to the [Egmore Museumwhere she could see ammonites and other fossils and she kept wanting to go back.

Aswatha giving a lecture. From The Better India (linked below)

From there, she started learning more about fossils and paleontology. She visited places where she could collect fossils and now has over 70! She’s become such an expert in Indian paleontology that she’s been invited to give seminars at schools and universities. Aswatha is well on her way to becoming one of the most knowledgeable paleontologists about Indian fossils. 

You can read more about her story at [The Better India].

Hello!

Remember me? A lot of things have happened since you last heard from me. I moved to a new city, had a baby, and got a tenure-track job. 2018 was quite the year. I’m hoping that 2019 is the year that I can make time to post on DrNeurosaurus again. However, since I’m still trying to make it through my first year in my new job, I will be posting less frequently, but I think I can do this once a month.

To that end, if you just can’t wait to hear from me, you don’t have to! Tonight, at 7pm eastern time, I will be live-streaming myself playing Jurassic World Evolution on Twitch. I can answer any questions on the dinosaurs you see, or general paleontology questions in REAL TIME! So come hang out with me tonight: twitch.tv/drneurosaurus.

Where in the World is DrNeurosaurus?

Hello friends. It’s been a while since I posted. I have not forgotten about you! I’m about 2 weeks away from meeting the tiny human I’ve been growing and have been running pretty low on energy. You may or may not know that the team involved in running DrNeurosaurus is just me. That means I don’t have any backup author to write posts when I can’t, and my recent life changes have made that more frequent than I would like.

Even though I’ve wanted to write posts each of these past weeks, I have not been able to. I will be returning to regular posting, but I need a few months off first. I will be starting a new job and caring for a new family member, and don’t anticipate much free time in the coming months. When I do return (hopefully in the early Fall), I will try to post at least once a month. As things normalize, I will hopefully be able to return to more frequent posting. See you soon!