Sunday, July 20, 2014

Saltasaurus: Prehistoric Animal of the Week

Enter Saltasaurus loricatusSaltasaurus was a sauropod dinosaur that lived in what is now Argentina, during the late Cretaceous period, between 70 and 66 million years ago.  It was small for a sauropod, measuring about forty feet from snout to tail.  Its genus name translates to "Salta lizard/reptile" in reference to Salta, a city near where it was discovered. 

Saltasaurus loricatus reconstruction by Christopher DiPiazza.

Saltasaurus is a pretty well studied sauropod.  There are many bones of it on the fossil record, but its real claim to fame was its skin.  Paleontologists found out, thanks to some beautifully preserved fossil remains, that Saltasaurus would have actually had small nodules of bone embedded in its skin.  We see these same sort of structures, called osteoderms, in modern crocodilians and other kinds of dinosaurs, most notably the ankylosauroids.  Never before had sauropods ever been known to have had armor!  It was always assumed that sauropods could get by with just their size, and perhaps tails as weapons.  It is is theorized that Saltasaurus had this dermal bone armor to help protect itself from predators since it indeed wasn't as large as some of its relatives.

Saltosaurus osteoderm fossil.

Saltasaurus belonged to a group of sauropods called the titanosaurs.  Since the discovery of Saltasaurus, other titanosaurs are commonly reconstructed with osteoderms too.  Like all sauropods, Saltasaurus would have stripped leaves off of branches with its teeth, which were only in the front of its mouth.  Titanosaur teeth were long and rod-shaped.  It also had a rather wide, barrel-shaped body, which probably was used for breaking down and fermenting all that tough plant material it was eating all the time.  Since its teeth weren't designed for chewing, Saltasaurus would have swallowed all its food whole and allowed its huge stomach chamber to do all the digesting for it, which would have required a lot of space and energy.  Just think of modern cattle and how big their stomachs are. (four chambers!)  There is a solid chance that sauropods like Saltasaurus also would have been very gassy animals because of this.  (teehee farts!)

Saltasaurus eggs have also been discovered.  They were almost perfectly round and only measured about five inches long in diameter.  Even more interesting, many clutches of these eggs have been discovered all nearby each other and even on top of each other year after year.  This suggests that like many modern reptiles, like certain turtles and birds, mother titanosaurs like Saltasaurus would have laid eggs at the same time in the same place each season.

Saltosaurus egg on display at the Museum of Ancient life in Utah, USA.

Saltasaurus, as well as titanosaurs as a whole, are important to paleontology because they proved that sauropod dinosaurs persisted successfully up until the very end of the Mesozoic era, 65 million years ago.  Prior to their discovery, it was believed that most sauropods died out at the end of the Jurassic period and were replaced by other plant eaters like the hadrosaurs and ceratopsians.  We now know that this is only true for the northern hemisphere.  In what is now South America, Africa, and Australia, sauropods were still the reigning plant eaters of their time!

That is all for this week!  As always please comment below or on our facebook page.  Have a request?  Let me know!

References


Coria, R.A. and Chiappe, L.M. 2007.Embryonic Skin From Late Cretaceous Sauropods (Dinosauria) of Auca Mahuevo, Patgonia, Argentina. Journal of Paleontology v81(6):1528-1532 doi:10.1666/05-150.1


Idols and Idolatry

Who is your idol?

I found myself asking this question to myself in the wake of the public scrutiny of the behavior of theoretical physicist Richard Feynman (I recommend reading Janet Stemwedel's in-depth examination of the situation). In short, he made important contributions to his field and is considered a brilliant scientist, but his actions towards the women he associated with professionally were extremely disrespectful, and arguably harmful to the goal of inclusion and fair treatment of women in science. Many in the field look to Feynman as a role-model or idol, and have responded harshly to the critiques.

The World English Dictionary defines idol as
"1. a material object, esp a carved image, that is worshipped as a god,
2. Christianity, Judaism any being (other than the one God) to which divine honor is paid,
3. a person who is revered, admired, or highly loved."

Dictionary.com has a different version of definition 3 for idol: "any person or thing regarded with blind admiration, adoration, or devotion. Madame Curie had been her childhood idol."

Both versions of the definition for idol carry with them an unrealistic burden to apply to any one person, and that burden comes with a heavy responsibility. Theoretical physics is not the only academic field in which idols exist. Every field has people who are treated as idols. There are idols in paleontology.

I had a couple of idols growing up, and I was fortunate in that I admired scientists who are also good people before knowing anything about their non-research conduct: they are ethical, fair-minded, and generous people. My early admiration of these scientists stood the test of time and my maturity. I still admire them, even though I have grown enough to realize that, although they are great scientists and great people, they will never be above scrutiny or critique. No one is.

Idols and role-models can be a potentially positive influence for young people looking to enter the sciences. They can inspire the younger generation to study. If their role-models write or appear for the public, they introduce young people to science concepts they might not otherwise encounter until their post-secondary education. Role-models inspire students to explore, to challenge old ways of thinking, and make the sciences so engaging that the students can see themselves participating.

There is a fine, fuzzy line between a role-model and hero worship, between a mentor and an idol. Idolatry can lead to mimicry, and while mimicry is supposedly a type of compliment, there are many examples in nature of toxic organisms being mimicked. It may be a heavy-handed analogy, but in the case of students, they may not immediately realize that the person they model themselves after is displaying behaviors that do more to erode the cooperative and inclusive goals of the scientific community than to uphold them.

I have come to find the idea of promoting someone to idol status disturbing. While we can cite examples of scientists who repeatedly demonstrate positive academic and community ethics, we should not promote the idea that any one should strive to "be like" another researcher. When a person is idolized, it is too easy to dismiss their less than noble actions for fear of tarnishing the shiny image, and those who critique the idol are portrayed as destructive. I have heard many say (and have stated this myself in my naive days) that it doesn't matter who the scientist is as a person as long as their academic work is sound, and that all that matters in the end is the product. I may have believed this once upon a time, but now I firmly believe this statement is a pile of steaming horse-apples.

Stemwedel hits the rock squarely with the Estwing:

'Do we have a scientist who is regularly cruel to his graduate student trainees, or who spreads malicious rumors about his scientific colleagues? That kind of behavior has the potential to damage the networks of trust and cooperation upon which the scientific knowledge-building endeavor depends, which means it probably can’t be dismissed as a mere “foible.”'


I realize that a scientist can be what I would colloquially describe as a jerk, a sleaze, or as dancing down the slippery slope of ethically dubious behavior and have also produced notable work. For example, I can't refuse to cite someone's paper just because I think how they treat their graduate students is despicable. However, their scientific contributions do not excuse or lessen the negative impact of their behavior on their community. They have set the stage for the conduct of future students on a shaky foundation. This should not be ignored.

How a scientist behaves towards their colleagues and subordinates professionally and personally is as important to the science community as their body of work, if for no other reason than they are maintaining the trail that the next academic generation will follow. All of the good within the community that currently exists is because of the attitudes fostered by our predecessors that we, knowingly or unknowingly, have internalized and are projecting as normal. The same applies to the negative actions that happen within our community. Whether we like it or not, whether we want the responsibility or not, our actions in and out of the field/lab are demonstrating what is normal for our field. We are demonstrating what we accept as acceptable behavior. It becomes our responsibility as soon as we start interacting with students.

It is also our duty to publicly criticizing behavior that we would not want to see demonstrated in our future students, regardless of the work conducted by the person/people. We have the responsibility to denounce the behaviors that sow mistrust, uncertainty, and even fear in the scientific community, and work harder to prevent them. If we do not want to see our future students 1) treat their peers or subordinates without personal respect, 2) treat underrepresented groups as inferior, 3) sabotage, undermine, or otherwise inhibit the work of their peers or subordinates, we have to model the type of behaviors that we want to see passed on to the next generation of students. We cannot excuse bad behavior as "part of the package" of doing research just because "it's always been done this way." If we receive criticism for our behavior, we have the responsibility to listen, examine, and change to foster a positive community.

In the end, the only people who are responsible for the climate we foster in our scientific community are ourselves. Sooner or later, someone is going to look up to you: who do you want them to see? More specifically, if you were on the receiving end of your actions towards your peers and subordinates, would you feel welcome in your scientific community?

Thursday, July 17, 2014

Field Work in New Mexico 2014

Greetings everyone!  It is time again to recap how Gary and I's time went last week doing field work in the badlands of New Mexico.  If you have not already, be sure to review my post about it from last year and also take time to read Gary's post from last week about his experiences excavating and prepping a specific fossil.

Sadly I can't give you detailed descriptions on everything we were able to dig up, nor can I post photos of prepped fossils that have not been published.  (I wish I could there are so many exciting new things over at the Mesalands Dinosaur Museum!) I can, however show you bits and pieces of our experiences over there that might give you a feel of what it was like. 

First things first lets look at the nature of the place.  As you know my background is heavily engrossed in biology, specifically the animal sciences, so whenever I visit a new ecosystem I am extra attentive to the creatures I can find around me.  Last year I saw two kinds of lizards.  This year I found another kind that I instantly recognized, a beautiful Collard Lizard!

Collard Lizard, Crotaphytus collaris, I managed to photograph in the field.

Collard Lizards get their name because of the black coloration that forms a ring around their necks.  Despite the fact that I didn't see any last year, they were the most common lizard I saw this year.  At the dig site I could Identify at least two individuals (a male and a female) who would appear nearby at least once per day.  The site must have become their territory sometime within the last year. 


I also managed to see a few Whiptail Lizards.  These guys have beautiful spotted patterns on their skin, and possess an extremely long tail.  (Which is how they got their name.)

One of the several Whitpails we also saw out there.  This one was eating a caterpillar.

On one of the last days there I found a solifugae!  (Not a dead one like last year) The little arachnid was running across the motel carpet!  Despite the alien (even creepy) appearance of this animal, I made sure to gently let her go on her way outside.  Arachnids are not generally harmful to humans and play an important role in hunting other small invertebrates. (cockroaches and mosquitos for instance) 

Solifugae I found in our motel room.  They can grow a LOT bigger than this.

 Speaking of cool invertebrates eating other invertebrates, we saw many beautiful dragonflies while in the field.  They would cruise around over the site in large groups, no doubt hunting the mosquitos and gnats that were pestering us.  Thanks, guys! 

This striking orange individual favored our truck's antenna as a perch.

 Once we actually started digging it wasn't long before fossils started turning up.  I was privileged enough to get the opportunity to help excavate a juvenile Typothorax armor plate.  We have found many plates from these amazing reptiles before, some over a foot wide!  This one, however was the same shape as one of the larger ones (so we know its not just from another part of the body on an adult) just tiny.  Video!


Gary made a pretty rare find while he was removing rocks from the site, a freshwater clam!  Remember, this site used to be the bottom of a lake 200 million years ago.  We find plenty of Redondasaurus, Typothorax, Shuvosauroids, and Coelophysis, LOTS of fish, but not too often do we actually find mollusks.  We almost mistook the clam as just another rock at first!  Video!


Overall it was a pretty successful week!  Gary came up with the idea that anyone working paleo out in the field should take "field selfies".  Lets do this! 

Gary Vecchiarelli
Our friend Donny, who is an intern at the Mesalands Dinosaur Museum, and currently working on phytosaur research!
Christopher DiPiazza (me)
Even paleontologist, Tony Martin, got in on the action from Montana!

That's all for this week!  Be sure to check out our facebook page for even more photos from the trip!  I have a few more videos I may put up there, as well! 

Sunday, July 13, 2014

Geisonoceras: Prehistoric Animal of the Week

This week we will be checking out an invertebrate which leaves behind some of the most beautiful fossils ever!  Enter Geisonoceras!

Life reconstruction by Christopher DiPiazza.

Geisonoceras was a cephalopod mollusk, related to modern octopus, squid, cuddlefish, nautolus, and the now extinct, yet highly successful ammonites.  Like them it would have possessed a soft, muscular body with tentacles and a sharp beak, as well as a hard outer shell.  It was most likely a predator, hunting trilobites and other arthropod prey.  Geisonoceras is a genus that contained many species which spanned over much of the world's oceans in a broad time long before the first dinosaurs, from roughly 460 to 390 million years ago.  This ranged across two two periods in prehistoric times called the Ordovician and Devonian.  The shells of this amazing mollusk range in size from a few inches to several feet long.  The name Geisonoceras translates to "Geison Horn".  A geison is a long architectural structure seen on ancient Greek buldings.  Geisonoceras possessed a long, slender, horn-shaped shell so the name fits! 

A rather large Geisonoceras fossilized shell on display at the Mesalands Dinosaur Museum in New Mexico.  If you look closely you can see that the stand for this fossil also contains smaller specimens within it!

The shell of Geisonoceras was long and pointed, and would have grown with it from birth.  However, the animal only lives in the first few chambers of the shell, as it is divided into walled sections that become more numerous, making the shell longer as the animal ages.  The shell also contained a hollow tube that spanned its length called a siphuncle.  This structure could be filled with water to control the overall density of the animal, allowing it to control its longitudinal movement in the water. 

That is all for this week!  As always feel free to comment below or on our facebook page!  Stay tuned for more coverage of Gary and I's trip to New Mexico for Triassic field work!

References

Walter A Sweet, 1964. Nautiloidea -Orthocerida, Treatise on Invertebrate Paleontology Part K, Endoceratoidea, Actinoceratoidea, Nautiloidea. Geological Society of America and Univ Kansas Press. Teichert and Moore (Eds)

Wednesday, July 9, 2014

A Taste of Fieldwork!


What is field work like for a budding paleontologist?  When it comes to the general public, a lot of folks believe it is as easy as finding a complete skeleton buried only under a few millimeters of dirt.  Perfectly preserved in a rigor mortis pose where the head is bent back towards the tail.  Although dinosaur skeletons can be found in great shape, paleontology rarely works this way.  Not to mention, field work can often turn up animals that lived at the same time as dinosaurs, but are not dinosaurs.

 photo tublr2.gif

Currently, I am in New Mexico hunting for Triassic beasts with the amazing Mesalands Dinosaur Museum. I have been a paleontology student during research here for many years in conjunction with my studies back home where I study geology.  That being said, I believe this would be a great time to take you though a day in the life of working in the field.  I have been fortunate enough to have made many fantastic discoveries over the years. I can not go into detail about most of what I have found because these discoveries are still being researched.  However, my professor and mentor has given me permission to use one find as an example for this aticle's topic!

During the summer of 2011, I found something magnificent.  My day in the field started off like many others.  I awoke at the crack of dawn and for good reason.  Getting an early start in the field means cooler weather for digging.  Temperatures out here can reach into the 100s!  Drinking plenty of water is key in order to not suffer from the heat.  I had just come off the heels of making a great find, so I was eager to start prospecting a new area within our site.  That is one subject I should touch on briefly.  Having an extensive background in geology is a vital key in the field.  Knowing the landscape and what time period your in makes tracking down a potential spot to dig a bit easier than aimlessly digging around.


It wasn't long before I began cautiously digging on the edge of our dig site.  It is very important to be careful when excavating a site.  Whacking away at rocks until you find something is not the way to go. Removing sediment and rock a little at a time is what it is all about.  Starting from the top and basically working your way down.  One piece at a time.  A strong amount of patience and skill will assure you do not damage whatever may be beneath the surface.  It wasn't long until luck had struck me again with a find.  At first, I believed I had found a tooth.  I couldn't be more wrong.  I would soon find out that my "tooth" was indeed something more wonderful.


Immediately after making a discovery, it is important to alert whomever is in charge of the field site.  In this case, my professor, mentor, and good friend, Dr. Axel Hungerbuehler.  At this point, precise measurements and documentations are made.  It is important to have proper recordings of what is found in the field.  This information is vital for later analysis of your find.  Orientation, level of elevation, and where precisely a fossil was found are just a few examples of documenting a find.  From this point on, getting the find out in one piece was all that went through my mind.  I diligently began working the rock around the find. Being careful to not displace the matrix in which my fossil was surrounded by.  Working off the over layers of rock is a good idea, but losing up the surrounding rock is also.  The Triassic stone in my area fit together more or less like a puzzle. By removing a corner piece a rock about a foot away from my find made it easier to remove rock closer to it.  Little by little, you need to think 10 steps ahead while trenching around a fossil.  Moving one piece may upset another and so on.  


You can see in the above picture that more and more of what was thought to be a "tooth" was now taking shape.  Sometimes you are lucky and the matrix will pop off your find in the field.  Although a Estwing hammer is shown in this photo, it was only used for scale.  Dental tools, small brushes, and very fine tipped tools were used in removing the surrounding rock.  On my belly, being very patient, I continued to trench around my amazing find.  For the first time in millions of years, a bone from an extinct animal was about to see the light of day again.


Soon my find was beginning to take shape.  A rib, but from what type of animal?  Where we excavate produces many extraordinary beasts.  Although dinosaur finds can be made, you are also likely to find other sorts of extinct animals.  In this particular case, we had what could possibly be a gastralium or belly rib of a Typothorax.  To the untrained eye, this animal can appear like an armored dinosaur.  In fact, Typothorax coccinarum was not a dinosaur at all and from a group called aetosaurs.  To further read about this animal, click HERE to see Chris's post.  He does a great job in describing this amazing animal.

Life reconstruction of Typothorax by Christopher DiPiazza.

After two days, my rib was finally exposed.  Two days!  Did I mention patience should be your best virtue in the field?  Yes, you must have patience.  It is very exciting to make a find, but you must take your time.  During the process of digging and after, special products were applied to keep the bone preserved.  You have to remember, this rib was seeing the light of day for the first time in millions of years.  When first exposed, it almost looked wet and appeared as if it was fresh off the animal.  When air hit it, the bone started to dry out almost immediately and it became very fragile.  Not all bones found in the field are robust and strong.  The video that follows is me removing the matrix from this magnificent find while a colleague looks on.

video

Below you can see the rib pretty much free, but before taking any further steps, we had to secure it.  Protecting fossils with a plaster jacket is sometimes needed.  This will ensure the bones safety until getting it back to the lab.  Once at the museum, we can take further actions to preserve a find.


In the following video, you can observe one of the crew members putting a field jacket on my find.  Our field truck rattles and shakes like crazy when climbing up the steep cliffs surrounding our site.  The next step will be to further protect the bone with padding and get it ready for the rough ride home.  There are no paved roads into where we go, so we don't want fossils getting banged around. We managed to get this rib out on the very last day.  Talk about perfect timing.  Next stop, the lab!

video

Once back at the lab we unwrapped the rib and the prepping began.  However, time was running and I would soon have to return home.  I would not have time to prep my find completely, but during my leave, the good professor carried on.  When I returned for my next field season, I was shown the finished work.  Wow, was all that ran through my mind.  There it was in all its glory.  Cleaned and prepped.  



Special thanks to Dr. Axel for his amazing work and help.  He is brilliant man, my mentor, and I will always be his appreciative student.