Q&A with Dalton Meyer ’25 PhD

From his earliest days, Dalton Meyer ’25 PhD (Earth and Planetary Sciences) knew he wanted to be a paleontologist. While dinosaurs were his first love, his curiosity led him to study mosasaurs, a group of giant lizards that evolved to become marine. A serendipitous meeting with a Yale researcher brought him to New Haven for his PhD studies.

In December, his dissertation was among the 40 awarded distinction, an honor given when all readers unanimously recognize the work as outstanding scholarship. The Graduate School conferred 197 PhD degrees in December. 

In a new Q&A, Meyer talks about how he unraveled a mystery in the evolutionary family tree of lizards and the importance of collaboration.

Tell me more about your research and key findings.

My dissertation was focused on lizards, but the findings are broadly applicable to a lot of the history of life. In biology, it’s critical to understand how different organisms are related to one another in the evolutionary family tree. There are several different ways that we can deduce that tree: Some of it can be done using molecular data, like DNA, protein sequences, things you can get from living things. For extinct organisms, you have to rely on the fossil record, which only preserves their anatomy.

However, sometimes those data disagree. And this isn't surprising—it happens fairly often—but within lizards in particular, there's a huge disagreement between what different kinds of data are telling us. Lizards are extremely diverse—there are over 12,000 living species of lizards, including snakes, and they have a fairly decent fossil record. So, while we've got this disagreement, there's a plethora of data we can use to try to find areas to solve that problem. I wanted to find out if we can use lizards as an example to figure out ways to solve this problem more broadly. Part of my dissertation focused on looking at living lizards and studying the anatomy of their ankles and wrists to try to find new pieces of information to infer their evolutionary history. And the other part was looking at different fossil species.

One of the fossils we examined was from Dinosaur National Monument near Vernal, Utah. It’s about 150 million years old, from the late Jurassic period. In the 1990s, researchers had identified it as a kind of skink relative, which is also found in England and Europe. And that was a very reasonable conclusion at the time. The fossil is kind of squashed. Using modern methods, including micro-CT scanning (a three-dimensional X-ray), we were able to isolate the bones, reconstruct the skull, and figure out the anatomy in greater detail than previous researchers. And that's when we realized that this is something that was unknown to science—it's a new species, and that it's one of the earliest relatives of geckos that we have in the fossil record.

I chose the name Helioscopos, which means sungazer, because it's got this hole in the top of the head, like a third eye. It's a light-sensing organ that's connected to the pineal gland in the brain. Ancestrally, all things with a backbone have that organ. Most animals today have closed that hole up, but most lizards still have it open. But modern geckos are, by and large, nocturnal. When the ancestor of modern geckos evolved to become nocturnal, it also closed that hole up. So, our animal preceded that; it was probably still active during the day, reliant on the sun, so that distinguishes it from modern geckos.

Did you have to travel to Utah to work with this specimen, or was it in the Peabody's collection?

I have gone out to Utah to see it, but that was actually after we did most of the study. When we were conducting the study on this specimen, it was using digital 3D data from the micro-CT scans, which is available for access by researchers, so I was able to look at and study that fossil in New Haven, while the fossil itself was still at the museum in Utah. A lot of the digital data from my dissertation came from other institutions who partner with a global consortium. I also generated a lot of new 3D data of specimens from the Peabody Museum.

How did you first become interested in this topic?

As far as I can remember, I've always wanted to be a paleontologist, since I was a small child. And dinosaurs were definitely my first love in paleontology, and I am finally getting to work on dinosaurs now. But when it came time to look at graduate school, I thought about what kind of scientific questions I was interested in. I find dinosaurs extremely interesting, but at that time, I couldn’t think of any questions that are central to dinosaurs that I needed to study. At the end of the age of dinosaurs, there was a group of lizards that evolved to become marine, and they became extremely gigantic—they're the mosasaurs. If you go to the Peabody, there's a mosasaur called Tylosaurus that's hanging up in the new atrium gallery, chasing the turtle. And if you've seen the new Jurassic World movies, the swimming creature in that is a mosasaur. They're a giant lizard. But one of the many debates in lizard paleontology is what are the closest relatives of mosasaurs? There are some researchers who think that they are closely related to snakes and others who think they're closely related to monitor lizards, like the Komodo dragon. Those are the two big camps. And initially, I thought, I want to figure that out. I want to solve that mystery. This is a really cool and interesting mystery involving lizards. There's a lot of modern stuff I can compare it to, so that was my plan coming into graduate school. And then in very short order, as I was learning more about lizards, I discovered that this mystery is bigger than mosasaurs. It goes across the entire family tree. I decided that I was more interested in the entire scope of this problem, rather than just one aspect.

How did you end up at Yale for your graduate studies?

Toward the end of my undergraduate studies at Colorado State University, I started looking at graduate school programs. I had a list of schools and researchers in paleontology. I was reading papers about mosasaurs, and a bunch of authors came up, including Yale Professor Jacques Gauthier (my advisor). Around that same time, I went to the Geologic Society of America conference in Denver, and I met some Yale graduate students at a recruiting booth. I said, I'm interested in vertebrate paleontology, and one of the students suggested that I talk to Professor Gauthier. We connected via email and later met in person at the Society of Vertebrate Paleontology conference in Calgary. We talked about my ideas and his research, and he encouraged me to apply to Yale.

The Peabody reopened in 2024 after an extensive renovation. Did the closure impact your access to the collection?

I arrived in 2018, and the Peabody closed in 2020. It was a really interesting experience being here for the Peabody renovation because I got to see it beforehand, which was really cool as someone who had been interested in paleontology for my whole life. I knew about the Peabody Museum, and I had seen photos of the displays, but I had never made it that far east to visit it. I finally got to see it when I came to do my interview.

It was tremendously educational to be around for that renovation. They had to move all the collections into temporary holding space. But during that whole process, they were still accessible to students and researchers. That was a huge priority for the museum, and I think they did an incredible job, because throughout the entire PhD process, regardless of what status the museum renovation was in, I was able to go to the collections, find the specimens I needed, take them out on loan, look at them, and study them.

And then being able to see the renovated Peabody after it was finished, being a part of that was incredible, both historically and personally. The old exhibits were definitely out of date, but historically very interesting, and now we've got this brand-new exhibit that is cutting edge. So that's been a wonderful experience. I think it was ultimately a very lucky time to be doing a Paleo PhD at Yale during that renovation.

Did you have opportunities to share your research with broader audiences while at Yale?

Yes, I did several outreach events at Yale. My first year, a group of graduate students put together a natural history lecture series for the community. After the museum reopened, I participated in student research spotlight program at the Peabody and gave group tours. They also have a great program where people who work in the collections do public outreach, talking about the specimens they work with.

It sounds like you had a strong relationship with your advisor. Did you have other collaborators or close colleagues at Yale?

The PhD cohort I came in with was really tight knit. The whole EPS program really shines with the relationships among the students and the postdocs. The postdocs in my lab were extremely helpful as mentors, teaching me research methods and collaborating on projects together.

Those relationships also opened other doors. For example, I have collaborators at other institutions, including at Stony Brook and Princeton. Getting that kind of experience was fantastic.

What are your career plans?

Right now, I’m a lecturer at Roanoke College, which is a liberal arts college in Salem, Virginia. I'm teaching natural science courses across biology, earth, and environmental science. Another great thing at Yale is that I was able to do all the research I could, but I also had a huge diversity of teaching experiences. It wasn't just grading papers; I was involved with running labs and helping out with lectures, which prepared me well for this career stage that I'm in now. I think my ideal permanent role is to be in a position that has an emphasis on teaching, but also doing research and helping support undergraduate research, which is especially important for young scientists who are getting ready to pursue a specialized graduate education.

Is there anything else that you’d like to share?

When I interviewed at Yale, a faculty member told me, “You can do anything here.” And I think that was such a true thing to say. I felt incredibly supported in my research and in finding opportunities to teach. It was not a program where you were competing with other students for resources or attention for projects. There were so many opportunities to collaborate and build communities across campus. Yale is just a really great place.