Interview with Paleontologist: Melanie During

Melanie During is a vertebrate paleontologist, currently employed as a research
assistant at Uppsala University in Sweden. She is Dutch and recently moved to Sweden
to begin her new job, while she continues to search for a fitting PhD program. Melanie
has a BS in Earth Sciences from the University of Amsterdam and a MS in
paleoclimatology from the VU (Vrije Universiteit) Amsterdam. A life-long fascination with
extinct fauna and evolution drove her to independently familiarize herself with vertebrate
morphology and comparative anatomy through elective courses (i.e. at Utrecht
University). During her bachelor and master education, she performed research on the
geochemistry, trackways, and vertebrate body fossils of Dutch early Middle Triassic
records exposed in the Winterswijkse Steengroeve quarry complex. This quarry, it’s
fossils and the citizen scientists who have been collecting there for more than 50 years
drew her to become increasingly involved in the excavations and research. Since 2015,
she acts as board member of the Workgroup Muschelkalk Winterswijk that seeks to
connect professional paleontologists with enthusiastic citizen scientists. This quarry also
led her to meet her life-partner, with whom she returns to the quarry every year to help
assist in the annual student excavations. For her master’s thesis, she studied fish and
dinosaur fossils from the unique Tanis locality (North Dakota, US). Here, latest
Cretaceous fossiliferous seiche deposits directly associated with the K-Pg boundary
event are preserved in exquisite detail. For this project she was able to do an
experiment at the European Synchrotron Radiation Facility (ESRF) in France, where X-
ray micro-computed tomography (μCT) and virtual segmentation was used to study
fossils without preparing them from the rock. This work, which is currently being
prepared for publication, was awarded the Dutch Escher Prize for the most outstanding
master thesis in Earth Sciences. Melanie studies tetrapod evolution broadly, but is
specifically interested in adaptations and extinctions. Specifically, the rise of the marine
reptiles prior to that of the dinosaurs during the Triassic, and the extinction of the
dinosaurs at the end of the Cretaceous, and how the selectivity of the K-Pg extinction
could be explained. She is still at the beginning of her career and is currently looking for
a vertebrate paleontological PhD program in Europe.

Pretending to be Mother Mary with a ¼ scale model of a T-rex skull.

Photograph by Juliën Kavish Lubeek.

Question 1: What was your first sign of interest in paleontology that you can
remember?

MD: As a young girl I was always playing outside and collecting rocks, spiders, bugs and
other things from nature. One day when I was around 7 years old, the municipality in
which I lived decided to replace the shells on the paths in the local park that I crossed to
get to school. As I walked to school the next day, I arrived hours late with pockets full of
shells, which I collected by carefully walking next to the path. As I was curious to some
of the shapes that I had never seen before, I went to the library and started comparing
the pictures to the shells I had found. When I finally found the comparison to some of
the shells, these turned out to be fossils, some of which even index fossils, for the
Miocene or the Eocene- and a fascination was born.

Question2: Did you have any family members or other people in your life who
served as role models when you were younger? 

MD: No, as a young girl I mostly played outside alone because no one in my family
understood my tendency to bring home dead things or rocks.

Question 3: Do you have any now?

MD: Oh, I have many by now. From citizen scientists, such as my ´surrogate mother´ Tineke
Lammerse to professionals such as Dr. John de Vos or to commercial paleontologists
as Pete Larson. They have all shown eager to teach me, take me out into collections or
into the field and discuss the fossils.

Excavating a piece of Triceratops parietal near Newcastle Wyoming in 2015.

Photograph by Pete Larson.

MD: Hmm, it would be hard to identify specific things or actions. If I would want to explainQuestion4: What specific things or actions do you feel most helped you get to the
point in your career where you are now?

how I got my Masters, from a low socio-economic background and three foster homes, I
think it is due to my stubborn perseverance.
My current position is that of a research assistant at Uppsala University in Sweden,
while I am also frequently hired to lecture to middle school, high school- and undergrad
students. All of these activities stem from my tendency to want to share my passion and
grasping onto every form of outreach that I could find.

Question 5: It seems that much of your work is with Triassic fossils.  Was this
something you specifically wanted to work with and sought out?  Or did it choose
you?

MD: In a way it chose me, since I am from the Netherlands, which has relatively few in-situ
fossils. The first time I visited the Winterswijk Limestone Quarry was in 2014, and for my
bachelor thesis I studied a section of 270 footprints from Rhynchosauroides peabodyi,
which are extremely plentiful in this quarry. The Triassic period is such a phenomenally
strange time; just after the largest known mass extinction and just before the dominance
of the dinosaurs-it is a period of rapid evolutionary radiation enabled by the great
number of empty niches.
Directly after handing in my bachelor thesis, the annual Winterswijk student excavation
commenced and I was in! Subsequently I wrote my first ever publication on a strange
vertebra from a durophagous placodont, I studied the bulk geochemistry of the entire
stratigraphy (to be published later this year) and I joined the citizen scientists working
group (Werkgroep Muschelkalk Winterswijk) in order to enhance collaboration between
collectors and researchers. Although I have also worked on the K-Pg extinction for my
master thesis and am currently working on late Devonian material, the early middle
Triassic marine reptiles of the Germanic Basin will always be among my favorite study
material and I look forward to working on them in the future.

Lifting a slab of fossiliferous Muschelkalk together with Dr. Dennis Voeten in

2019. These big slabs were subsequently passed on to students who would use their

hamers and chisels to make them smaller and look for fossils. Photograph by Prof.

Anne Schulp.

Question 6: What has been your favorite project so far?

MD: Beyond a doubt that would be my master thesis, which is still unpublished, so I cannot
say too much about it. However, I can mention that I worked on the material from Tanis
(North Dakota), where the last day of the Cretaceous was preserved in phenomenal
good condition. The material contained so many ´firsts´ for me, including: first time I
studied fossils that were buried as they died, first time I found soft tissues, first time I got
to use synchrotron μCT analysis and 3D modelling techniques, and the first time I
managed to directly answer the research question I initially asked prior to any analyses.
In other words, a little patience and I’ll happily share it with the world once the paper is
out.

Question 7: What are you working on right now?

MD: I am currently employed in the lab of Per Ahlberg at Uppsala University in Sweden,
where I model synchrotron microCT data of Late Devonian coprolites, which aid in the
PhD project of Hannah Byrne. Hannah is currently studying the biotic transition at the
Devonian-Carboniferous boundary, and coprolites are very informative if you want to
figure out who ate whom. For those unaware, coprolites are fossilized excrement, or
poop. It´s a shitty job, but somebody´s gotta do it –pun intended ;).
This research assistant position is a perfect bridge between my masters and my future
PhD, I am further developing useful skills and working in a great team where I will
expand my network. I admit I am somewhat picky when it comes to PhD positions and
the ones I want are heavily competed for, therefore hopefully this job will increase my
chances and I am definitely not bored or unhappy in the meantime

“Preparation day” 2017, a day for the Workgroup Muschelkalk Winterswijk in

which citizen scientists and professionals share their findings and discuss preparation

methods. Photograph by Jos Lankamp.

Question 8: I know you have a pretty great twitter account.  How do you think
social media plays into your profession? 

MD: Wow, thank you! In all honesty I have only recently passed the 1000 followers mark, but
it went relatively fast from there. My social media is an enormous outreach outlet to me,
trying to offer motivation and encouragement to current students, offering evocative
information to potential future paleontologists and sharing some inside information with
my international colleagues. It has offered me a direct link to journalists and
paleontologists whom I would otherwise have never met. The majority of my invited
lectures actually come from sharing my field-experiences directly on twitter and this has
a direct effect on my lecturing experience. One day I hope to create paleontological
documentaries and I am 100% sure that having an extensive online network will help
with that.

Excavating Triceratops material (at least a Femur and Tibia are clearly in

view) for Naturalis in the summer of 2015. Photograph by Prof. Anne Schulp.

Question 9: Where has paleontology taken you geographically?  What is your
favorite place you have spent time in so far?

MD: Oh wow, well I’d have to separate a few things then. So, paleontology has taken me
places for study and work, it has taken me places for conferences, it allowed me to
meet my partner Dr. Dennis Voeten who I visited in many places, and it has taken me
places for fieldwork.

I have done the majority of my education in the Netherlands, in Utrecht and in
Amsterdam, with an internship at the Black Hills Institute for Geological Research in
South Dakota, US. Currently I am employed in Uppsala, Sweden. I have attended
conferences in Grand Rapids, MI, US; Berlin, Germany; Opole, Poland; Lyon, France;
Munich, Germany; Brussels, Belgium (and several in the Netherlands). I have met
Dennis Voeten in Winterswijk, while he was doing his PhD in Olomouc, Czech Republic
and Grenoble, France, where I traveled to frequently, and I have done fieldwork in: the
Netherlands, Belgium, Germany, France, Spain, UK, Scotland, Poland, US.

Question 10: Do you ever get criticized on any of your work?  How do you react to
it?

MD: Oof, yes, often enough. I find that criticism on my work is actually tremendously helpful.
Although I may not always agree with the criticism, I`m very welcoming to other points
of view and sometimes it shows me that I just did not explain my reasoning well enough
and there is something to gain.
Criticism on my work is actually not the only criticism I get, and I have had a great deal
of criticism directed at my work, which was actually criticism on my flamboyant
personality, my big mouth or my non-academic activities. That sort of criticism has
caused me a great deal of sadness several times and I have both learned to make sure
that I take all the necessary academic steps to prevent them, as well as the develop
broader shoulders and wave my pink hair prouder than I ever have before.

Question 11: Where there any forms of media or entertainment that you think
helped fuel your interest in paleontology?

MD: Hmm, well, my interest in paleontology is continuously fueled through (social) media
today and in the past 10 years. As a child however, I grew up without cable and with
expensive dial-up internet and I didn’t even see the Jurassic Park movies before
becoming an adult. The public library was all I had and it certainly fueled my interest.

Melanie “riding” a T-rex Stan replica during her internship at the Black Hills

institute for Geological Research. Photograph by Peter Larson.

Question 12: Some people say that paleontology doesn't do any real good for
humanity and is just a "for fun" field.  What are your thoughts on this view? 

MD: Honestly paleontology will likely never cure cancer or solve today’s great problems of
humanity. Calling it a “just for fun” field, however stems from looking directly at the
current world’s problems and then at what paleontology does to solve them, which is
cherry-picking.
Paleontology, like many of the STEM fields, focuses on the cores of long-term
problems. Bit by bit and step by step, as the centuries go by, we learn and understand
more about life on Earth. These are never-ending fields, and we will likely never answer
all the questions, since the answer of one question typically results in more new
questions. In the process, however, we have learned that the Earth is round, and it’s the
third planet in our Solar System, which is about 4.6 billion years old and has inhabited

life for about 3.8 billion years. Life has experienced at least 5 mass extinctions and over
99% of all species that ever lived are now extinct. Diseases such as we humans suffer
today, are found back in fossil bones dating back to at least the Triassic (about 240
million years ago) and are therefore nothing new. Paleontology is the non-written history
of Earth´s life´s past, it has already happened, and studying this history provides us with
an insight in the future, a future that includes climate change and mass extinctions.

Dissecting a modern Ostrich for comparative osteological analysis, in 2016

in my backyard in Amsterdam North, photograph by Sander Liem.

Question 12: Who was the first paleontologist you met?  How did that go?

MD: The First paleontologist I ever met was Dr. John de Vos, at the time curator at Naturalis
Biodiversity Center (the National Natural history museum) in Leiden and Teylers
museum (oldest museum in the Netherlands) in Haarlem. He gave a guest lecture in the
elective course “Big History”, during the course I asked just a bit too many questions
and he quickly suggested I talked to him after the lecture. After the lecture I happily
came up to him and he gave me his card: “Send me an email and I’ll give you a tour
through the museums, you can be a paleontologist too, don´t let anyone tell you any
differently!” Needless to say, I followed his advice. After the two tours through the
museums he introduced me to several more Dutch paleontologists, including Prof. Jelle
Reumer who supervised my subsequent bachelor thesis.

Question 13: Why do you think prehistoric animals are so influential to humans?

MD: In a way they test your imagination. When I studied the footprints of Rhynchosauroides
peabodyi, I was studying at least 13 individual trackways, some overlapping and some
clearly deposited later than others. I could not help but imagine a soft of Persian Gulf,
where all these reptiles would wander over the tidal flats.
Paleontology takes you back to times when nature was still unaffected by humans, I’m
not saying it was much better then, because for instance Winterswijk was a hypersaline,
dry and hot environment during the early Middle Triassic. Yet imagining that on this
Earth, where you now walk and find a fossil, this animal actually walked around and
lived out its entire life under very different and yet very similar circumstances. What was
it? Under what circumstances did it live? How did it move? What did it eat? How did it
die? Are the most basic questions and every answer will lead to more questions. It just
tickles your brain a little. In my case it makes me extremely curious and it is that
curiosity that makes for such fanatic paleontologists.

Melanie together with Prof. Anne Schulp, drawing out swimming traces in the Winterswijkse Steengroeve in 2015.  Photograph by Remco Bleeker.

Question 14: What is your favorite prehistoric animal? Why?

MD: Oh dear, every time a child raises their hand after my lecture to ask me this question, I
fall completely silent. Honestly, this is one of the hardest questions there is and I´m
genuinely afraid I give a different answer every time I get it.
Therefore, today I will say it´s the Placodont, a shell-crushing marine reptile from the
early Middle Triassic, with big fat pachyostotic bones and elaborate palatal dentition (flat
and wide teeth all across the roof and bottom of its mouth).

However, tomorrow I may say Nothosaurus, or Triceratops, perhaps the day after I’ll say
Oviraptor or Titanosaurus. Although I’m mostly fond of Mesozoic reptiles, I’m not really
focused on which one is my favorite and as long as it has a spine, I’d be interested in
studying it.

Melanie during the fieldwork for her master thesis in ‘Tanis’ North Dakota

(US). Photograph by Jackson Leibach.

Question 15: If you could go back in time and observe any prehistoric time
period/community, what would it be?  Why?

MD: I would love to observe the K-Pg extinction, although I expect that to be a little painful to
witness. It ties in with all my interests, from Earth Sciences to astronomy to
paleontology and it has literally kept me up at night wondering how this catastrophe led
to such a discriminating mass extinction.

Question 16: Back to the time machine.  If you could bring back any animal from
earth's history back to modern time to observe alive, what would it be and why?

MD: The very first living organism.

Question 17: What is your favorite museum?  Why?

MD: Teylers Museum in Haarlem. It is the first and oldest museum in the Netherlands and to
this day largely maintains its original architecture, interior and collection. Teylers
Museum is the only museum in the Netherlands that has been open to the public
continuously since 1784. It is home of the “Haarlem specimen” of Archaeopteryx*,
which John Ostrom himself could borrow when he thought it was misidentified as a
pterosaur. The museum was also extremely welcoming to house the 14 th annual
meeting of the European Association of Vertebrate Paleontology (EAVP), for which I
was in the organization committee. To this day, this is one of the most remarkable
experiences of my life, seeing 200 paleontologists make their way through 19 th century
cabinets full of fossils and other scientific curiosa to attend conference sessions.

*most recently it has been identified as Ostromia crassipes, but it would not surprise me
if this is not the last name it will ever have.

The group photo of the 14 th annual EAVP meeting at Teylers Museum in

Haarlem in 2016, Melanie is located in the bottom left (pink hair, green top).

Question 18: What are your hobbies?  (doesn't have to be paleontology-related)

MD: Hobbies? I don’t have time for hobbies?! -No I’m joking, I absolutely think hobbies are
vital for life.
Let’s see, other than paleontology, my time is spent on:
-Singing (in bands, on stage, or just at home while doing the dishes)
-Acting (in commercials or films)
-Painting, drawing and crafting in general.
-Sewing. I made a dinosaur dress for my thesis defense and try to make clothes every
now and then. My machine will finally come to Uppsala next week and I’m trying a fun
new project I named:” Everything can have pockets” where I attempt to give all my
clothes pockets.
-Repairing. Whether it’s a flat tire on my bike or my car needing new brake-pads, I like
figuring things out and getting my hands dirty.
-Going out to festivals, rock shows or parties. Fun is to be had!

Wyoming at night with the Milky way in 2015. photograph by Servaas Neijens.

Qianzhousaurus: Beast of the Week

This week we will be looking at an unusual theropod that earned the nickname, "Pinocchio rex".  Check out Qianzhousaurus sinensis!

Qianzhousaurus was a meat-eating dinosaur that lived in what is now southern China, during the late Cretaceous, between 72 and 66 million years ago.  From snout to tail it measured about twenty nine feet long.  The genus name translates to "Guangzhou Reptile" in reference to Guangzhou, the city near where its bones were discovered.

Life reconstruction of Qianzhousaurus sinensis by Christopher DiPiazza.

Qianzhousaurus was a member of the tyrannosaurid family, so it was actually a very close relative of the famous, Tyrannosaurus rex.  However, Qianzhousaurus was much more lightly built and probably a faster, more agile runner than its more famous relative.  Most notable, however, is Qianzhousaurus' extremely long, narrow snout.  This snout was proportionally longer than that of any other known tyrannosaurid's.  The exact funtion of such a feature is mostly a mystery, but perhaps it specialized in hunting a different sort of prey than what commonly assumed for a tyrannosaurus.  A narrow snout may have helped Qianzhousaurus snap up smaller, faster prey, or continue to pursue small prey even if it was hiding in a burrow or other small space.  The longer snout may also have been an adaptation for scavenging, being able to reach more pieces of meat in hard-to-reach crevices on a carcass other carnivores wouldn't have access to.

Hooded Vultures form Africa use their specialized bills, which are much longer and narrower than those of other vultures, to reach pieces of meat off carcasses their competitors cannot access.  Qianzhousaurus' snout may have served a similar purpose.  (photo taken by me at the Berlin Zoo.)

Inside of Qianzhousaurus' jaws would have been long, sharp teeth, which were certainly ideal for processing meat.  It also had small ridges down the top of its snout and a thin, triangular bony crest right between its eyes which may have been extended with keratin in life to form a decorative structure of some sort for intraspecies display.

Skull of Qianzhousaurus from Junchang's 2014 paper.  Note the small ridges over the nostril and triangular crest just before the eye socket.  These structures may have been covered in more extensive keratin to form a display structure in life.

No arms were ever found from Qianzhousaurus, unfortunately.  That being said, if it was indeed a true tyrannosaurid, it likely only would have sported two fingers on each hand, like all of its relatives.

That is all for this week!  As always feel free to comment below or on the facebook page!

References

Junchang Lü, Laiping Yi, Stephen L. Brusatte, Ling Yang, Hua Li & Liu Chen, 2014, "A new clade of Asian Late Cretaceous long-snouted tyrannosaurids", Nature Communications 5, Article number: 3788 

Adratiklit: Beast of the Week

This week we will be looking at a newly discovered dinosaur that also breaks a few records!  Let's check out Adratiklit boulahfa!

Adratiklit was a plant-eating dinosaur that lived in what is now Morocco, in Northern Africa, during the middle Jurassic period, about 168 million years ago.  The genus name translates from Berber to "Mountain Lizard" and the species name is for Boulahfa, the part of Morocco where it was found.  From snout to tail it could have measured roughly twenty feet long, but this is only based on fragmentary remains.

Life reconstruction of Adratiklit in watercolors by Christopher DiPiazza.  This is mostly educated guesswork since only a few bones are known.

Adratiklit is exciting because it is the oldest known member of the stegosaurid family, being from the middle Jurassic, 168 million years ago.  Stegosaurids, of which Stegosaurus is the most known member, were plant-eating dinosaurs that had proportionally tiny heads, bony plates on their backs, and spikes on their tails.  All other known members from this group lived several million years later, in the late Jurassic, around 150 million years ago give or take a few million years depending on the taxa.  The other interesting thing about Adratiklit is that it lived in what is now northern Africa, an area that no stegosaurid has ever been found in before.

A vertebra from Adratiklit.  Image from Maidment's paper listed below.

Adratiklit is only known from a few bones, including vertebrae and a humerus.  That being said, paleontologists were still able to identify these bones as being from a stegosaurid of some kind thanks to a number of diagnostic characteristics.  Based on the details of these bones, they were also able to deduct that Adratiklit was most likely most closely related to stegosaurids that lived in Europe, like includes the long-necked Miragaia and the slightly less mysterious Dacentrurus.  There were other stegosaurids that lived in Africa, like the extremely spiky Kentrosaurus, but its bones were found in what is now Tanzania, which despite being on the same continent, is geographically very far away from Morocco.  In fact, Morocco is actually a bit closer to Europe than it is to Tanzania.  (People often forget how gigantic Africa is.)

Since Adratiklit is only known from such fragmentary remains, a lot of the specifics of how it looked in life are a mystery.  Since it was a stegosaurid, we can assume it had plates and spikes growing out of its back and tail, but their shape, lengths, and arrangement, all of which vary depending on the taxa, we can only guess.  Did it have mostly plates and only four spikes on the tail like Stegosaurus?  Perhaps it had more spikes all the way up its back like Kentrosaurus?  Did it have a long neck, like Miragaia?  Maybe we'll find out one day if more of this amazing dinosaur is discovered?

References

Maidment, Susannah C. R.; Raven, Thomas J.; Ouarhache, Driss; Barrett, Paul M. (2019-08-16). "North Africa's first stegosaur: Implications for Gondwanan thyreophoran dinosaur diversity". Gondwana Research.

Reconstructing Hadrosaurus for the Academy of Natural Sciences

As you may have known from my facebook, instagram, or Twitter, I had the honor and privilege of working for the Academy of Natural Sciences, in Philadelphia, producing a life-sized reconstruction of the famed dinosaur, Hadrosaurus foulkii, to accompany their mounted skeleton in March this past year.  Doing a professional piece of this dinosaur, that was discovered in my home state and has been one of my favorites since childhood, has been dream come true and the whole experience was fun and educational for me from beginning to end.  Part of the process was me getting interviewed about Hadrosaurus and paleoart.  As is the case with any filmed interview, there was a LOT that I said that needed to get cut so it would fit in the small segment that is now on loop for the public to view at the exhibit.  The final cut that is currently being played at the museum is linked below.  Today I would like to share with you the entire process, and some more detailed tidbits that you may not get by visiting the exhibit, alone.

The reconstruction is part of the annually rotating "Drawn to Dinosaurs" part of the exhibit at the Academy.  Every year, a different artist is hired to produce a life-sized life reconstruction of Hadrosaurus on the wall behind the skeletal mount in chalk.  The idea behind the concept is to showcase how different paleoartists can have greatly differentiating visions of the same animal but still be equally scientifically accurate.  It also is a great opportunity to visually showcase new discoveries about dinosaur anatomy each year, instead of having a permanent reconstruction that will inevitably become outdated as time goes on.

I actually reached out and applied to the Academy two years ago with a proposal to do the job, but was initially turned down for that year.  It's easy to get frustrated in times like that, but it's so important to stay positive and keep moving forward.  This field is filled with countless skilled artists each with their own styles and backgrounds.  I feel it's more productive to celebrate and get inspired by my peers, instead of seeing them as competitors or rivals.  Their success has no affect on the quality of my work.  Only I am in control of that.

The next year I proposed my ideas to the Academy again.  This time with a sketch of what I planned to do if given the opportunity.  Having seen the Hadrosaurus reconstructions from years past by other paleoartists, like Jason Poole and Ray Troll, I wanted to make sure mine was different, but still scientifically accurate.

Concept sketch proposal I sent to the Academy of Natural Sciences for how I'd depict Haddie.

A few months later I received an email saying I had been chosen!  (It was actually a response to original proposal from the year before) I had about six months to prep myself and prepare to create the physically largest piece of paleoart of my life. (twenty five feet long and fifteen feet tall to be exact)

Fortunately, I was already comfortable drawing Hadrosaurus with regards to the proportions and colors.  I did, however, feel a need to practice with using the medium I was required to use the day of, chalk, which I had little experience with outside drawing on the sidewalk as a kid.  I popped into the museum on two separate days and played around with the chalks they had on hand on a chalkboard in one of their back rooms.  First I thought that since I would be working on a black background, I would try filling in the light spaces with the chalk and leaving the shadows and dark spaces as the black of the board, which is the opposite of what I do with most other mediums, which take place on a white background.  Ultimately, I still found it easier (for me) to simply to fill in the entire body with the base color and then work in the shadows with darker colored chalk.

One of the practice doodles I did playing around with chalk on a rolling blackboard leading up to doing the life-sized Hadrosaurus.  This version uses the black of the board for the darks and shadows, which I ultimately did not do for the final product.

The day finally arrived for me to put Hadrosaurus on the wall!  Many times when you see large pieces that take up most of or an entire wall in museums, it is created on a smaller scale by the artist, first, then blown up digitally and printed at a larger scale to be hung up.  Not the case here.  I had to draw the dinosaur directly onto the wall, all twenty five feet of it!  Further, I wasn't doing this behind the scenes.  This was taking place live over the course of two days on the actual exhibit, while the museum was open to the public, during an annual special dinosaur-themed event!  So thousands of people walked by and watched me.  Many had questions as I was working, too, which I had a lot of fun answering.  The Academy set up a camera that was filming me from beginning to end.  You can see the time lapse of the entire process below.

Among the thousands of people who came by to watch, there were a few familiar faces I was most happy to see.  Almost my entire team from my work at a nearby middle school stopped by.  Paleoartist, and longtime mentor of mine, Larry Felder made the trip over to show his support.  The Academy's resident dinosaur paleontologist and paleoartist, Jason Poole, was a steady presence and was extremely helpful with his input on the environmental pieces of the scene, having done this piece four years prior.  Paleontologist, Ted Daeschler, also was frequently checking in and kindly made a point to express how much he was enjoying my work.  Lastly, my family, including the person I was most excited to see, my wife, came by to show their support.

From left to right: Larry Felder, Me, Jason Poole.

I made a point to include lots of important details in this reconstruction of Hadrosaurus.  They aren't necessarily listed in the information under the exhibit and they may not even be visually obvious to everyone walking through.  Luckily, if you're reading this, I can list them for you.

Colors

The first three versions of this piece from the prior years all showcased a mostly green color scheme.  I really wanted to show something different, but still totally plausible.  I decided to stay mostly true to the  colors I chose for Hadrosaurus from a painting I did back in 2015.  This color scheme uses drastic countershading brown and white, with black markings on the face.  This was partially inspired by various birds that live in wetland/brackish water environments which would have been similar to the places Hadrosaurus may have been frequenting in life.  It also reminds me of many of the cool marsh birds I see when I spend time at the Jersey Shore, geographically very close to where Hadrosaurus actually roamed millions of years ago.

First painting I did of Hadrosaurus showcasing this color scheme from 2015.

The alternating bands on the tail is consistent with a lot of animals today, and when seen in reptiles, produces an illusion when the animal is moving.  As a long form with bands moves horizontally, it becomes difficult to the viewer to pinpoint where the form ends and begins.  This may have been a helpful adaptation for Hadrosaurus when dealing with potential predators.  Lastly, we actually have fossil evidence, thanks to exquisitely preserved mummified skin of a close relative of Hadrosaurus, Edmontosaurus, discovered in 1999, of a banding pattern on the tail.  The specimen has different sized scales arranged in a banding pattern, suggesting there may have been different colors there in life.

If you look closely, you can see the permanent outline of the underlying profile of the dinosaur that I ultimately made longer and thicker.

The black and white stripes on the legs could have been a communication adaptation for signaling to members of the same species, like a potential mate, or young.  We know thanks to fossils from a close relative of Hadrosaurus, called Maiasaura, that baby dinosaurs from this family were able to walk around on their own from a very small size.  A parent may have wanted its young to follow him/her for safety, like we see many species of ground birds do today, but the size difference between parent and young would have been extremely drastic, and therefore actually dangerous for the young in a way.  A parent Hadrosaurus may have had a rough time keeping track of all its brood at times.  There is also a chance mom/dad could accidentally squish one of its own young if not paying attention enough.  If the parent had bold markings on the feet and legs, it could act as a beacon at the level of its babies that could stay visible even in areas with thick vegetation that would otherwise hinder visibility.  We also know that animals alive today use black and white stripes to help deter biting insects.  A recent study on zebras show that the drastic striping pattern confuses flies that would otherwise suck blood from the larger animals.  Prehistoric dinosaurs probably had to put up with parasites and bloodsuckers, just like large animals do today, so a pattern like this may have been helpful on this front.  This is all just a hypothesis, of course, but it's fun to think about.

My Hadrosaurus has red and pink coloration on the snout and throat.  This is simply for display.  Many animals alive today, including relatives of dinosaurs, like birds and other reptiles, use bright colors like this to communicate fitness to rivals and potential mates.  I also gave my version an extensive dewlap, the loose skin under the chin and neck, similar to those you can see in many modern lizards for display, as well.

The black stripe over the eyes is an adaptation to being out in the sun.  Since dark pigments absorb light, having dark colors over the eyes helps cut glare from the sun so the animal can see more easily when it is bright out.  Many animals utilize this adaptation today that live in open environments, like the marshy floodplains Hadrosaurus may have frequented in life.  Even baseball and (American)football players put black paint on their faces during games for this exact reason!

Black markings near the eyes help minimize glare from the sun that would reflect into the eyes.  It is a common adaptation with animals that spend time in flat open spaces with little shade.  For the same reason, many athletes put black paint on their faces when they're playing on an open field.

Beak and Scales

The beak of my reconstruction is much longer and more down-turned than what you would see on the skull.  Thanks to mummified specimens of other kinds of hadrosaurid dinosaurs, like two separate specimens of Edmontosaurus, we know they would have had an extra layer of hard tissue over the beak that was made of keratin in life.  In fact, it turns out that these dinosaurs, despite being nicknamed "duck-billed dinosaurs" because of the shape of the beak of the skull alone, probably had beaks that were less flattened like that of a duck, and more downturned in life because of this layer of keratin.

We now know that hadrosaurid beaks were longer and more downturned than what the skull suggests.

My reconstruction of Hadrosaurus, as well as the four reconstructions that were done in the same place before me, have a single row of rectangular scales down the length of the back.  This isn't a coincidence.  This is based on the fact that paleontologists found a mummified specimen of a close relative, called Brachylophosaurus, which preserved impressions of these structures down the animal's back.  I took a few liberties with the shape of these, especially around the head and neck, making them more spine-like, than rectangular, since Hadrosaurus was still a different species, and therefore probably didn't look exactly the same in every way.  These structures may have been for display or they could have helped break up the dinosaur's shape making it more difficult to track by potential predators.

You can see the faint outlines of where the plate-like dorsal scales would have been on the mummified dinosaur, "Leonardo" in the top photo, compared to the similar structures I gave Hadrosaurus in the bottom photo.

We know thanks to multiple mummies of relatives of Hadrosauarus, that these dinosaurs were covered in non-overlapping scales that looked like mosaics.  Despite how much I wanted to do this on my reconstruction, I only had two days to complete it and therefore not enough time to draw in every single scale.  However, I chose to draw many scales over much of the dinosaur, giving the illusion, especially when viewed from several feet away or further, that the dinosaur was completely covered in them.

Cast of fossilized skin from the tail of a hadrosaurid mummy on display in front of the Hadrosaurus skeletal mount at the Academy of Natural Sciences with my wall art.  Original specimen is in the collections of the American Museum of Natural History, in New York.

If you look really closely at the leg, you may notice a several scales arranged in a shape that might look like an angry black cat.  This may or may not be a secret homage to my cat, Petrie.

If you look closely at Haddie's leg...you might see Petrie!

One particular specimen of an Edmontosaurus regalis shows us an impression of what the skin on the neck would have looked like, which had proportionally larger, wider scales.  I made a point to show something similar to this on my Hadrosaurus, as well.

Comparison to the fossilized neck skin imprints from Edmontosaurus regalis from Bell's 2013 paper.

Muscles

There is a permanent basic outline of the dinosaur on the board for the artist to draw over, just to keep the shape and general pose intact.  However, because of some recent discoveries, I needed to greatly extend my drawing past this outline.  Thanks to many of these mummies that have been mentioned already, we know that hadrosaurids were much bulkier and more heavily muscled than previously thought.  The neck of my reconstruction is much thicker than the outline and shows plenty of folds and wrinkles as the dinosaur bends its neck upwards.

Until recently, if you looked at dinosaur reconstructions, you might notice that the legs would be separated from the tail, like you might expect for any animal, including lizards and crocodilians.  Thanks to some beautifully preserved mummies of hadrosaurids, however, we now know that there was a huge muscle connecting the back of the leg to the base of the tail on each side of the dinosaur.  this makes more sense, since these animals were much heavier, bipedal, and therefore needed more power in that region to walk around.  If you look at the muscles of modern birds that are strong runners, like ostriches, or even chickens and turkeys, you will see the same muscles.

The tail in general on my reconstruction is much thicker overall.  The ischium, the bone in the pelvis that is angled downwards and backwards under the dinosaur, would have been completely covered by flesh in life, despite sometimes being visible in older reconstructions.  We know thanks to the famous Edmontosaurus mummy, nicknamed Dakota, that these kinds of dinosaurs had very thick tails like this.

Environment

I wanted to include other organisms that Hadrosaurus may have interacted with in life in my reconstruction.  We know thanks to beautifully preserved specimens of other hadrosaurids that still had their last meal in their stomach cavities, that these dinosaurs were eating pine needles in life.  We have fossils from trees similar to modern redwood trees from the same general time as Hadrosaurus, so I included a small tree based on this, for my Hadrosaurus to munch on.

We know, thanks to a pretty extensive fossil record, that birds were alive and well during this time.  We don't have many fossils from this time in North America, and even fewer that show any characteristics that give us a good idea of what they looked like in life, but we know they were definitely around in some form.  I liked the idea of a symbiotic relationship between birds and larger dinosaurs, like certain species of birds have today with other large animals.  Oxpickers, native to Africa, are specialized in eating blood-sucking parasites off of large animals, so I created a bird based off of them with regards to beak shape, but with different colors, to accompany my Hadrosaurus.  Again, this is mostly educated guesswork of something that could have been, but isn't necessarily supported by hard evidence...yet.

There is currently no fossil evidence of birds specifically adapted to symbiotically eating parasites off of prehistoric dinosaurs, but the possibility is always there.

I included another species of bird behind my Hadrosaurus as well.  Since we know Hadrosaurus was frequenting a brackish marshy habitats most likely, I wanted to see if there were any sort of shorebirds or wading bird fossils found from that time.  Turned out there are fossils in the form of tracks from a wading bird, similar to modern herons and storks, from China during the early Cretaceous, millions of years before Hadrosaurus.  Since birds are so widespread, I decided, with some input from Jason Poole, that a wading bird similar to this would be totally plausible and safe to include in my reconstruction.  The birds I depicted have the diagnostic long legs and long toes like the tracks show.  I took more liberties with the neck and beak, however, to be a bit less specialized.

We have fossil evidence that wading birds were flourishing by the time of Hadrosaurus.

Lastly, I included possibly my favorite invertebrates, horsehoe crabs.  Horsehoe crabs we know have been around since hundreds of millions of years before the first dinosaurs.  Since there are horshoe crabs frequenting the shores of New Jersey today, it is possible their ancient ancestors were doing the same back then.  I drew inspiration from the countless horseshoe crabs I've found washed up at the Jersey Shore, many of which had entire communities of barnacles and bivalves living on their shells.

Now you know a bit of the thought behind my Hadrosaurus at the Academy of Natural Sciences.  As I stated earlier, this is a yearly exhibit, so in March of 2020, it will be replaced by the work of another artist, so if you ever find yourself in or near Philadelphia in the next year, make a trip over!

References

Bell, P. R.; Fanti, F.; Currie, P. J.; Arbour, V.M. (2013). "A Mummified Duck-Billed Dinosaur with a Soft-Tissue Cock's Comb". Current Biology. 24 (1): 70–75.

Caro, Tim, et al. “Benefits of Zebra Stripes: Behaviour of Tabanid Flies around Zebras and Horses.” PLOS ONE, Public Library of Science, journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0210831.

Morris, William J. (1970). “Hadrosaurian dinosaur bills — morphology and function“. Contributions in Science (Los Angeles County Museum of Natural History) 193: 1–14.

Murphy, Nate L.; Trexler, David; Thompson, Mark (2006). ""Leonardo," a mummified Brachylophosaurus from the Judith River Formation". In Carpenter, Kenneth (ed.). Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs. Bloomington and Indianapolis: Indiana University Press. pp. 117–133.

"Mummified Dinosaur Unveiled". National Geographic News. 2007-12-03. Retrieved 2007-12-03.

Osborn, Henry Fairfield (1912). "Integument of the iguanodont dinosaur Trachodon". Memoirs of the American Museum of Natural History. 1: 33–35, 46–54.

Xing, Lida, et al. “Reanalysis of Wupus Agilis (Early Cretaceous) of Chongqing, China as a Large Avian Trace: Differentiating between Large Bird and Small Non-Avian Theropod Tracks.” Plos One, vol. 10, no. 5, 2015, doi:10.1371/journal.pone.0124039.

Vespersaurus: Beast of the Week

Today we will be looking at a truly unique, recently discovered species of dinosaur.  Let's check out Vespersaurus paranaensis!

Vespersaurus was a theropod dinosaur that lived in what is now Brazil, during the Cretaceous Period, about 90 million years ago.  From snout to tail, Vespersaurus would have measured a little over six feet long.  The genus name translates from Latin to "Western Reptile" in honor to Cruzeiro do Oeste (which means Western Cross), the town where the bones were uncovered. 

Vespersaurus paranaensis life reconstruction in watercolors by Christopher DiPiazza.

Vespersaurus was a member of the noasaurid family.  Noasaurids were theropods that primarily flourished in the Southern Hemisphere during the Cretaceous period and are within the larger, more diverse ceratosaur group, which includes more famous dinosaurs, like Ceratosaurus and Carnotaurus.  Unlike these larger relatives, however, noasaurids tended to be much smaller, and more lightly built, with longer necks and proportionally smaller heads.  Another, recently more popular noasaurid, and therefore much closer relative to Vespersaurus, was Masiakasaurus, which was found in Madagascar and had a distinctive, down-turned lower jaw with teeth that jutted out forward.  Because so little of Vespersaurus' skull was found, it is unknown if it had a similar down-turned jaw or not.  If it did, Masiakasaurus may not be that unique, and the trait might just be a more widespread ancestral adaptation to the noasaurid family.

Articulated foot of Vespersaurus.

When it came to Vespersaurus' legs and feet, however, it truly was unique.  In fact, Vespersaurus' feet are unlike anything ever seen before in reptiles, let alone dinosaurs!  Vespersaurus had what are called functionally monodactyl feet.  This means that the animal was only using one toe on each foot to actually walk.  In the case of Vespersaurus, it had the first digit of each foot was higher on the leg and didn't touch the ground (typical for nonavian theropods), but the second and fourth digits, which normally would touch the ground in other dinosaurs, were unusually thin and would have been carried off the ground when walking.  All the weight was put on its third digit.  Amazingly enough, prior to the discovery of Vespersaurus' bones, paleontologists found very strange tracks from Argentina which show what appears to be a theropod dinosaur walking on its central toe.  These tracks are a bit older than Vespersaurus, and they possibly could have only simply appeared to have been only walking on one toe, and the side toes just weren't making as deep of an impression, but they are still important to note.  We know dromaeosaurids, the group that includes Velociraptor, carried one specialized toe off the ground and walked on two, and there are modern birds (also dinosaurs) that have only two toes on each foot, like ostriches, but only one walking toe in dinosaurs is completely unheard of until this.

One-toed theropod track, possibly an earlier relative of Vespersaurus.

Vespersaurus certainly had unique feet for a dinosaur, and even a reptile, but this sort of foot plan HAS evolved before...just in a different group of animals.  In fact, it happened in a very popular group of animals that everyone knows, horses!  Everyone knows horses only have one hoof per foot, which is just one big toe.  Fortunately, we have a very detailed fossil record of horse ancestors, which shows that millions of years ago prehistoric horses were walking on three toes, and over time the side toes grew shorter and eventually became useless, leaving everything to the middle toe, ultimately resulting hooves we recognize today.  It makes me wonder if Vespersaurus had not gone extinct if its descendants would have had only one toe per foot, too.  Since Vespersaurus lived 90 million years ago, tens of millions of years before the mass extinction event that wiped out the non-avian dinosaurs, maybe there was a later, more derived noasaurid that has this foot plan that paleontologists just haven't found?

Illustration of prehistoric horse foot bones.  Oldest to youngest from left to right.  Note how side toes become smaller and eventually disappear, leaving a singular, walking toe.(image from Outlines of Zoology, by J. Arthur Thomson.)

So why the unusual one toe on each foot?  Well, if we go back to horses, which have a convergently similar adaptation, we may get some clues.  We know horses evolved these feet to run faster.  When the weight of an animal's foot is on a more concentrated spot, it provides more resistance against stress when weight is applied on it, and therefore results in a stronger runner.  Looking at the rest of Vespersaurus' known bones, it makes sense that it would have been a very fast runner.  It also lived in an arid desert environment, with lots of open space, where being able to run long distances more easily would certainly be an advantage.  What environmental pressures would have caused Vespersaurus to have evolved such an extreme running adaptation?  Unfortunately the diversity of fossils from the site Vespersaurus was found in is still limited, Vespersaurus being the only known dinosaur so far, so we have no idea what kind of predators it would have had, if any.  On the other end, Vespersaurus had small teeth that were short, but serrated, so it was possibly at least eating some meat.  Perhaps Vespersaurus was really good at chasing down small prey? It's still a mystery!

Tooth of Vespersaurus.

That is all for this week! Comment below with your thoughts!

References

Glut, Donald F. (2003). "Appendix: Dinosaur Tracks and Eggs". Dinosaurs: The Encyclopedia. 3rd Supplement. Jefferson, North Carolina: McFarland & Company, Inc. pp. 613–652.

J. Arthur Thomson, M.A., LL.D. Outlines of Zoology (New York, NY: D. Appleton & Company, 1916)

Langer, Max Cardoso; de Oliveira Martins, Neurides; Manzig, Paulo César; de Souza Ferreira,, Gabriel; de Almeida Marsola, Júlio César; Fortes, Edison; Lima, Rosana; Sant’ana, Lucas Cesar Frediani; da Silva Vidal, Luciano; da Silva Lorençato, Rosangela Honório; Ezcurra, Martín Daniel Ezcurra (2019). "A new desert-dwelling dinosaur (Theropoda, Noasaurinae) from the Cretaceous of south Brazil". Scientific Reports. 9.

“Mechanics of Evolutionary Digit Reduction in Fossil Horses (Equidae).” Proceedings of the Royal Society B: Biological Sciences, royalsocietypublishing.org/doi/full/10.1098/rspb.2017.1174

Alanqa: Beast of the Week

Today we will be looking at an interesting pterosaur, Alanqa saharica!

Alanqa was a pterosaur that lived in what is now Morocco in Northern Africa, during the late Cretaceous Period, about 95 million years ago.  It was a relatively large pterosaur, with an estimated wingspan of up to twenty feet in the largest known individual.  The genus name translates to "phoenix"in Arabic in reference to the mythical bird.  When alive, Alanqa was most likely a meat eater.

Alanqa saharica life reconstruction in watercolors by Christopher DiPiazza.

Alanqa isn't known from too much fossil material, mostly beak and a vertebrae, but judging by these pieces, and comparing them with the proportions of other more completely known pterosaurs that were related to Alanqa, we can get a decent estimate of its overall size.  Alanqa was a member of the Azhdarchid family of pterosaurs.  Azhdarchids were primarily dominant during the Late Cretaceous and produced the largest animals to fly of all time, let alone the largest pterosaurs.  They are characterized by having proportionally huge skulls (longer than their torsos) with long tapering beaks devoid of teeth.  Many also had extremely long, but not very flexible, necks.  Azhdarchids are also thought to have been comfortable walking on land, even though evidence shows they could fly very well and for long distances, too.  A modern analog that is often made for them is today's storks and herons. (Although it is important to note that birds are NOT the same as pterosaurs.  They are purely convergent to each other.)  The extremely large Quetzalcoatlus, is the most well-known member of this family.

Part of Alanqa's beak.  Image from Ibrahim's 2010 paper.

The front of Alanqa's beak was narrow and pointed, like an extremely large pair of tweezers, great for targeting and plucking prey out of specific places, which typical for azhdarchids.  However, farther back in Alanqa's jaws were protrusions growing from the upper and lower parts of the beak, that would come together as the jaws closed.  It reminds me of the tool used to crack lobster shells, to be honest, and this very well may be what these unique adaptations were used for!  Alanqa very well may have been a specialist in eating prey with shells, like crustaceans, mollusks, and maybe even turtles?  It's also a possibility that Alanqa was an efficient scavenger and used these bony structures to crack open bones to get to the marrow inside?  I can imagine Alanqa wading around in shallow water with the narrow tip of its beak submerged, moving from side to side or probing into the mud as it uses its sense of touch to scan for any hiding prey.  When it finds something it grabs it with the tweezer-like front of its jaws then cocks its head back to maneuver the food item to the back, where it is cracked to pieces and swallowed!  This is all just speculation, of course.  But the fact of the matter is Alanqa did have a cool, unique adaptation of some kind in the back of its jaws.  We may never know for sure its purpose!

This is basically Alanqa's face...just tiny and made of metal.

That is all for this week!  As always feel free to comment below!

References

Ibrahim, Nizar; Unwin, David M; Martill, David M; Baidder, Lahssen; Zouhri, Samir (2010). "A New Pterosaur (Pterodactyloidea: Azhdarchidae) from the Upper Cretaceous of Morocco". PLoS ONE. 5 (5): e10875.

Martill, David M; Ibrahim, Nizar (2015). "An unusual modification of the jaws in cf. Alanqa, a mid-Cretaceous azhdarchid pterosaur from the Kem Kem beds of Morocco". Cretaceous Research. 53: 59.

Witton, Mark P.; Habib, Michael B.; Laudet, Vincent (15 November 2010). "On the Size and Flight Diversity of Giant Pterosaurs, the Use of Birds as Pterosaur Analogues and Comments on Pterosaur Flightlessness". PLoS ONE. 5 (11): e13982. 

Dakosaurus: Beast of the Week

You may know that we have reviewed a Godzilla dinosaur on here before.  This week we will be looking at yet another prehistoric beast with connections to the "King of the Monsters."  Check out Dakosaurus andiniensis!

Dakosaurus andiniensis lived in the oceans that once covered what is now Argentina during the Late Jurassic to the Early Cretaceous, between 145 and 140 million years ago.  Dakosaurus was a meat-eater in life, and measured about fifteen feet long from snout to tail.  The genus name, Dakosaurus, translates to "biter lizard/reptile" in reference to the creature's formidable teeth.  There are actually a few species within the Dakosaurus genus, but I want to focus specifically on the species, Dakosaurus andiniensis.  

Dakosaurus andiniensis by Christopher DiPiazza.

Dakosaurus was an extinct genus of crocodilian that belonged to the family called Metriorhynchidae.  Metriorhynchids were prehistoric crocodiles that were specially adapted to living in the ocean during the middle Jurassic through the early Cretaceous periods.  Their limbs were like flippers and their flattened tails even independently evolved flukes like those of sharks, dolphins, and their fellow reptiles, the ichthyosaurs and mosasaurs.

Fossilized skull of Dakosaurus andiniensis.  It looks mean!

Dakosaurus andiniensis had a uniquely short snout compared to the other species within its genus, giving it a particularly menacing look, to the scientists who studied it.  It is because of this unusually short, and boxy face, that this species of Dakosaurus was nicknamed "Godzilla" among the scientists who worked with it.

Dakosaurus' teeth were unique in that they were both laterally compressed and serrated.  This is a feature more commonly seen in certain kinds of meat-eating dinosaurs.  In fact, when the isolated teeth of Dakosaurus were first discovered, they were initially believed to have been from a Megalosaurus, not a crocodile.  The skull of Dakosaurus had openings towards the back, called fenestrae, that would have anchored powerful jaw muscles in life.  This, combined with the fact that its teeth were deeply rooted within the jaws, means that Dakosaurus would have been able to bite down with extreme force.  It is likely that an adult Dakosaurus would have been a top predator and was able to hunt most other animals it shared its habitat with, including other marine reptiles. 

Nobody is exactly sure how Dakosaurus would have reproduced.  There is specific fossil evidence that other prehistoric marine reptiles, like mosasaurs and ichthyosaurs, gave birth to live young in the water.   Dakosaurus' group, the crocodilians, however, only lay eggs in nests, however.  In fact, even broadening this group to all of archosauria, which includes crocodilians, in addition to dinosaurs and several other reptile groups, all we know of is egg-laying so far.  Going off this information alone, using closest relatives as a reference, Dakosaurus would have needed to haul out on land to lay its eggs.  However, a study looking at the anatomy of a more completely known metriorhynchid showed that the anatomy of the pelvis was more similar to that of other kinds of marine reptiles that we know gave birth to live young.  Despite that all known archosaurs lay eggs, it wouldn't be unheard of for one group of marine crocodilians to have evolved live birth, since we already can confirm it has happened multiple independent times in other groups of reptiles.

Closeup photo of the tail of a Dakosaurus, including imprints of skin.  You can also see scars the animal had in life left on its skin from external parasites, like barnacles, perhaps.  Photo from Spindler et al.'s research paper published in 2021.

Lastly we have fossil evidence of what the skin of Dakosaurus probably looked like!  Since it was a crocodilian, one might assume it had chunky chainmail like armor and scaly skin, like its modern relatives, but this wasn't the case.  It appears, thanks to a beautifully preserved specimen discovered in Germany, that Dakosaurus had smooth skin that lacked any visible scales or scutes.  This is consistent with other lineages of reptiles that evolved fully marine lifestyles, like ichthyosaurs and plesiosaurs.  This may have been an adaptation to be as streamlined as possible to better maneuver in the water.  

That is all for this week!  As always feel free to comment below.

References

Gasparini Z, Pol D, Spalletti LA. 2006. An unusual marine crocodyliform from the Jurassic-Cretaceous boundary of Patagonia. Science 311: 70-73.

Herrera, Y.; Fernandez, M.S.; Lamas, S.G.; Campos, L.; Talevi, M.; Gasparini, Z. (2017). "Morphology of the sacral region and reproductive strategies of Metriorhynchidae: a counter-inductive approach". Earth and Environmental Science Transactions of the Royal Society of Edinburgh: 1–9. 

Spindler, Frederik, et al. “The Integument of Pelagic Crocodylomorphs (Thalattosuchia: Metriorhynchidae).” Palaeontologia Electronica, 2021, doi:10.26879/1099.

Vignaud P, Gasparini ZB. 1996. New Dakosaurus (Crocodylomorpha, Thalattosuchia) from the Upper Jurassic of Argentina. Comptes Rendus de l'Académie des Sciences, Paris, 2 322: 245-250.