Crosbysaurus from Utah – Author Interview

Today, we published “The first occurrence of the enigmatic archosauriform Crosbysaurus Heckert 2004 from the Chinle Formation of Southern Utah”. In this blog post, Robert Gay comments on his research and experience publishing with us.

Robert J. Gay

Robert J. Gay

PJ: Can you tell us a bit about yourself?

RG: I am a high school biology and paleontology teacher at Mission Heights Preparatory High School, a small public-charter school in rural southern Arizona. I have a bachelor’s degree in biology from Northern Arizona University in Flagstaff, Arizona. I run the nation’s only public school paleontology program; we have collections, students are actively engaged in field and laboratory research, and (obviously) eventual publication. I am also pursuing a Master’s degree at the University of Arizona in the Culver Lab, looking at ways to apply population analysis software to morphological data with the hopes of eventually applying these techniques to fossil populations. Additionally I’m working on a project with the Museum of Northern Arizona looking at possible collections biases within their extensive collection of Kayenta Formation fossils. Fun facts about me? My earliest memory is of my mother reading to me from a dinosaur book when I was two years old, my favorite extinct animal is Dilophosaurus, and I have several paleontology-related tattoos.

Isabella "Bella" St. Aude

Isabella “Bella” St. Aude

PJ: Can you briefly explain the research you published in PeerJ?

RG: While in the field last May my coauthor found several small, unusual archosaur or archosaur-like teeth near our camp. She initially suspected that these were “baby dinosaur” teeth based on the fact that they were A) very small and B) unlike the phytosaur and metoposaur teeth we were recovering in droves. Phytosaurs (a group of crocodile-like archosaurs) and metoposaurs (giant amphibians with toilet-seat-like heads) both have very distinct teeth, mainly conical and generally robust. Bella’s teeth were obviously different so she brought them to my attention. I knew right away that these things weren’t phytosaur or metoposaur so we looked at them more closely back in “the lab.” It became clear that at least one of the teeth (the one we have written this paper on) belonged to a poorly-known archosauriform known as Crosbysaurus. This is an animal that likely looked something like a plant-eating crocodile, but since no remains of it besides the teeth have been found we don’t really know for sure.

We very quickly realized that this animal had never been reported from Utah before. I’ve been doing fieldwork in the Moab area with Andrew RC Milner and the St. George Dinosaur Discovery Site for several years now and we have yet to come across any teeth like this. A literature review supported this. We were very excited because not only is the the first occurrence of this animal in Utah, but it also represents the northernmost location this animal has been found. Several other paleontologists use Crosbysaurus as a biostratigraphic index taxon and since the area we are working, Comb Ridge, has seen little stratigraphic work it may prove useful in providing a relative age for the lower part of the Chinle Formation in this location. To that end our final accepted manuscript includes the first detailed stratigraphic section of Comb Ridge. Previous work has been on a large scale and focused only on the upper section accessible by road cuts. We think that this stratigraphic section coupled with a good stratigraphic position of the tooth will be useful to other researchers as well as our own future work.

PJ: Do you have any anecdotes about this research?

RG: I am a big proponent of trying to get more women into STEM fields. It has been refreshing for me that the trips we have had so far have had an equal gender ratio. I hope this trend continues not just here, but throughout their post-secondary careers. I’ve seen the stats that say women in undergraduate programs tend to be roughly equal in numbers to men, but decline as you “move up” through the ranks. Anyway, it is nice to know that at least in our program women and men are getting the same exposure to the field.

PJ: What surprised you the most with these results?

RG: I was most surprised with two things: the unusual morphology of our Crosbysaurus tooth and the stratigraphy. The tooth we describe in the paper is different from pretty much every other Crosbysaurus tooth in the literature. Perhaps the oddest feature is the mesial (or forward-facing) edge of the tooth. All other specimens of Crosbysaurus in the literature have denticles along the entire mesial surface, from tip to base. These mesial denticles are then subdivided into accessory denticles. This would be like your serrated knife having small serrations on each large serration. Our tooth doesn’t have this at all. The mesial denticles are not subdivided and they are restricted to the portion of the tooth closest to the tip. This isn’t some accident of preservation. Below the last mesial denticle the enamel of the tooth is intact. So that told us the denticles were not just worn off; they were never there in the first place. There are some other minor differences in the profile of the tooth and the number of accessory denticles on the distal (or backward-facing) denticles between our tooth and other Crosbysaurus teeth as well, but none were as striking as the mesial denticles. In fact Bella and I had a few discussions about whether this tooth represents a new species of Crosbysaurus based on those differences and the geographic distance between it and otherCrosbysaurus specimens. In the end we decided to simply say it was Crosbysaurus sp. because A) the idea of a “species” in paleontology is rather contentious B) there are already quite a few tooth-based taxa from the Triassic that have been lumped and split. It didn’t seem like adding another name to the mix, based on one isolated tooth, would help the situation. C) without non-dental remains we have no idea if the different part of Crosbysaurus‘s jaws had different tooth shapes. Most Triassic archosauriforms do not seem to have much heterodonty, but we can’t rule it out either. Animals were doing weird things in the Triassic Period.

The second surprising result was the stratigraphy. The Utah Geological Survey has the Chinle Formation at Comb Ridge mapped in as Petrified Forest Member pretty much exclusively. If you look at the preprint revisions you’ll see that this was our assumption as well. Other authors have looked at the upper section of Comb Ridge and said that it is the Owl Rock, or the Rock Point, or the Church Rock member. We feel that the upper member is in fact Church Rock, in line with Martz et al. (2014), but the lower member is definitely not anything that has been proposed before. This isn’t too surprising since no one seems to have looked at it in depth. Doing the full measured section definitely changed how we are seeing this portion of Comb Ridge. This summer we are doing fieldwork, supported by the Canyonlands Natural History Association, to help figure out the relationship between the lower member at Comb Ridge and the surrounding areas. It doesn’t look like the Cane Springs of further north. Is it equivalent to the nearby Monitor Butte Member? Maybe. Two weeks of detailed paleontological and stratigraphic fieldwork should help get closer to answering that question.

Illustration of Crosbysaurus by Robert Gay

Illustration of Crosbysaurus by Robert Gay

PJ: What kinds of lessons do you hope the public takes away from the research?

RG: There are two things I hope the public can take away from this. One is that science isn’t some ivory-tower pie-in-the-sky endeavor that only wealthy academics (getting rich off of their grant money) participate in. Here we have high schoolers not just engaged in fieldwork, but like my coauthor, engaged in all aspects including testing a hypothesis and publishing the results. We aren’t a well-off school. We raised the money for this project by bake sales! Bake sales to do science! Students were selling cookies and muffins every day after school to get the money to get out and do the fieldwork. With the right support and guidance, some types of science (like paleontology) can be accessible to anyone.

The second is that science is constantly changing. That’s one thing I love about preprints (and open review) is that you can see how ideas have evolved based on feedback, new publications, etc. As I mentioned above we originally concluded that the portion of the Chinle Formation our tooth came from was the Petrified Forest Member. That has completely changed as we came across new information and performed additional experiments (measuring our stratigraphic section). It is okay to be wrong as long as you recognize and correct your mistakes. I always ask my students, “Would you rather know you are wrong or think you are right?” Almost all say they’d rather know if they are wrong. The public needs to understand that if new evidence shows up scientists (and “science”) will change or potentially even reverse earlier positions they held. That’s okay. I think there is a lot of public distrust in science because non-scientists don’t understand that basic premise of science.

PJ: You’re a high school teacher. What did your students take from this experience?

RG: Science is a lot of work. Most science students think that science class is hard, no matter what (my coworker who teaches chemistry gets this from his students’ parents constantly, “Chemistry class was so hard for me!”). What most of them don’t realize is that science class in high school (and even to some degree as a college undergrad, especially for non-majors) is just scraping the surface of what scientists are doing. Taking my students into the field and getting them to collect the data I required from them there opened their eyes. Preparing the specimens back at the school was more work than they thought. Finally writing up the paper and responding to reviewers and feedback on the preprints involved far more research and work than students had expected. Several of my students still want to go into a science career after going through this program. I think that this sort of exposure to real world science will help them make informed decisions about their post-secondary careers. College is expensive and if they are unaware of what sort of work it takes to do science, but want a science career then we haven’t served them well.

PJ: Where do you hope to go from here?

RG: Since last May we have gone back to Comb Ridge once to measure a stratigraphic section and once to prospect for fossils. Unfortunately we as a school don’t have an vehicles, let alone SUVs, so our rental vehicles were not able to get us to the localities I had planned to prospect so we found very little. We will be returning in May (when the roads should be better) to continue our prospecting. We received a grant from the Canyonlands Natural History Association to run a field school this summer with eight students, myself, and a field assistant. We will be in the field for two weeks with a primary aim of screening the microsite where this Crosbysaurus tooth came from (named The Hills Have Teeth by my coauthor and other students), prospecting for new localities, and measuring detailed stratigraphic sections along the entire western face of Comb Ridge.

Students are also working with me on a manuscript about one of the other unusual teeth discovered last year. I hope that we can submit a manuscript as a preprint by the end of May.

I also intend on continuing my work with Andrew and others in the Moab/Canyonlands area. Knowing the fossils and geology of that area well will continue to be useful in trying to make the regional correlations with our work at Comb Ridge.

PJ: If you had unlimited resources (money, lab equipment, trained personnel, participants, etc.), what study would you run?

Well, in addition to everything mentioned above, I’d be looking at detrital zircon dating along our measured sections, paleomagnetism work, stratigraphy along nearby Elk Ridge to try and correlate the lower member of the Chinle Formation, tons more field time to prospect for (and hopefully excavate) other specimens, including more complete organisms. I’d also spend a lot more time prospecting the Kayenta Formation along the top of Comb Ridge. This summer we will spend a day or two doing this, but I want to make sure we don’t miss anything. If we can get good dates and generally good strat sections across Comb Ridge it should go a long way into tying this little slice of the picture (which hasn’t really been studied) into the larger picture of the end of the Triassic on the Colorado Plateau.

PJ: How did you first hear about PeerJ, and what persuaded you to submit to us?

I heard about PeerJ over a year ago. I believe it was a tweet from Andy Farke. At the time I was running a biology class looking at the local plant life in a mountain park and thought that it would be perhaps neat to submit their findings as a preprint. When I saw that PeerJ offered the option of a preprint I decided to run with it. I saw that paleontology was one of the topics covered and have enjoyed reading the preprints in that area. I knew that when I had more paleontological research ready to go to review I would give PeerJ a shot. I am a big open access advocate, especially being at a small institution like Mission Heights. Having my students (to say nothing of my colleagues and the general public) be able access the articles I write can only help them learn about the scientific process.

PJ: Do you have any anecdotes about your overall experience with us? Anything surprising?

The reviewers comments were very helpful. So much so that they shifted our entire geologic understanding of the area and resulted in our detailed strat column. The speed, especially on our final decision, was very quick. That’s a nice surprise! We submitted our last major revisions, got back minor revisions, submitted the minor revisions, and got our “accepted” decision within a 24 period. The other revisions took longer to process on our end, but the initial decision was also very quick while still being very thorough. I’ve heard some people complain that open access journals sacrifice review quality in order to get speed. I didn’t find that to be true in our case. Another bonus for open reviews: people who have concerns about whether the peer reviews were satisfactorily rigorous can look through the review history!

PJ: Did you get any comments from your colleagues about your publication with PeerJ?

Yes. In addition to Facebook and e-mail comments on our preprint, we received two pieces of feedback on PeerJ’s site directly. Both were good, though the second bit of feedback we received was after the manuscript had started to go through review and lots of the comments we got in that feedback had already been addressed. In fact that is why we released another version of our preprint – so that the most recent changes could be seen and people would know that our thinking (and the content) had changed a bit. It might be nice in the future if PeerJ had a notification like “this preprint is current in peer review”, similar to the “read the peer reviewed version” that already exists. That way viewers would know that changes might be coming. Nonetheless, we did receive good feedback.

PJ: Would you submit again, and would you recommend that your colleagues submit? 

Yes to both. My colleague Andrew and myself currently have a preprint on an armored tetrapod from the Kayenta Formation in Utah out on PeerJ ( that we hope to revise and send to review soon. In addition, part of our grant agreement with CNHA for our summer fieldwork is that results are preferentially published in open access journals. I anticipate that at least some of our results will be submitted to PeerJ.

PJ: Anything else you would like to talk about?

Some of my students also recently made comments on several PeerJ preprints. I was reviewing the comments today with my students and many of them had their feedback “accepted” by authors. Some of the comments were grammatical in nature, but others were about the core science of the preprint. A few authors even replied to the student comments. I think that not only is it good for students to see that they can interact with scientists, but their contributions can be valuable. They may be approaching these issues in a slightly different way than the authors and that can be helpful for everyone involved.

PJ: In conclusion, how would you describe PeerJ in three words?

Fast. Rigorous. Open.

Join Robert and thousands of other satisfied authors, and submit your next article to PeerJ.

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