Our Triceratops fossil, Cliff, did not live in New England. So what kind of dinosaurs did? We ask two local experts, Mark Agostini and Dr. Mark McMenamin, to tell us what fossils have been recovered from our own backyard.

We ask questions submitted by listeners, so if you have a question you'd like us to ask an expert, send it to us at sciencequestions@mos.org.

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Various images of fossils found in Massachusetts.

You can read the full scientific paper on the Nash specimen here!

ERIC: From the Museum of Science in Boston, this is Pulsar, a podcast where we dig up answers to the most interesting questions we get from our visitors. I'm your host, Eric, and we are lucky enough to have one of the most complete triceratops fossils known to paleontology on display in our exhibit halls. We've answered visitor questions about this fossil, nicknamed Cliff, such as how do you brush its teeth? But since Cliff was discovered in the North Dakota Badlands, a famous fossil hotspot, visitors have asked: what about New England? What dinosaurs roamed this part of the earth? And what evidence do we have that can tell us about them? While the Museum of Science has had Cliff on display for just over fifteen years, we have another specimen in our collection that was presented to us in 1864, when the museum was known as the Boston Society of Natural History. This sandstone slab originally unearthed in Connecticut dates from the Jurassic period. Within this slab of rock known as MOS 2001.248 are the fossils of several bones of a small dinosaur that roamed ancient New England two hundred million years ago. To learn more about the dinosaurs of our backyard, and even the research that is still being conducted on the fossils in our exhibit halls, I turned to two local dinosaur experts. Mark Agostini is a Ph.D. candidate at Brown University in the Department of Anthropology, and Mark McMenamin is a Professor of Geology at Mount Holyoke College. We discussed the New England dinosaur tracks and fossils that have been found so far, the never-ending search for more evidence, and even a serendipitous dino discovery. Mark and Mark, thanks so much for coming to the museum today and being on the podcast.

MARK A: Thanks for having me.

MARK M: We're happy to be here.

ERIC: So today we want to talk about the dinosaurs of New England, and we just don't have that much evidence of them. Not many fossils of their skeletons. Why is that?

MARK M: Well, there's a lot potentially exciting about geology and paleontology here in New England. The main problem has been the glaciation which has covered over our bedrock exposures with lots of glacial till.

ERIC: So those glaciers kind of took away our ability to see layers of time? Like, are there fossils, but they're way under the ground, and we just couldn't get to them?

MARK M: That's exactly right, Eric. The fossils are there. We just have to dig for them to get them.

MARK A: And historically speaking, you get westward expansion later, going into the, you know, 1860s, 1870s. And that's really where you get the paleontological discoveries of the West, you know, the Cope and Marsh Bone Wars and things. But where paleontology really got its roots was here in New England with folks like Edward Hitchcock, who was a theologian and also a very gifted scientist. And he is the person credited with really describing the fossil footmarks, or footprints that are really the main indicator of dinosaurs having lived here in the eastern seaboard, particularly New England.

MARK M: Yeah, Hitchcock was an incredible milestone. He compared the abundant tracks in the Connecticut Valley to those of birds, which was an idea that was kind of rejected in his time, but it's had a return, shall we say?

ERIC: Yeah, the last couple years, it's dinosaurs and birds. We know a lot more about that connection than we used to.

MARK A: And Hitchcock was indeed ahead of his time, you know, pointing to this avian connection to birds. It's kind of interesting, because the people that really took dinosaurian paleontology, they maintain this kind of more reptile connection. But the avian connection is sort of pushed away for many years until it's kind of revamped much later in time.

MARK M: So now we know that birds are in fact, living dinosaurs. That's just an incredible revelation. And their early evolution is something we'd like to learn more about. And that's why the Connecticut Valley strata are important. They're early Jurassic in age. And that's right where we need to know more about dinosaur evolution. So we need to get to work finding those guys.

ERIC: One of the things in New England that we definitely have is footprints. Can you talk a little bit about why we have those footprints? Is it a particularly good area for them?

MARK M: Well, it was a particularly good area for preserving those types of ichnofossils, the footprints or tracks, because of the fact that the supercontinent Pangea was ripping apart. It formed a rift valley, lakes formed, the dinosaurs were walking along the shore of the lakes, and these lakes would bury themselves over time preserving the tracks. The problem with our wonderful track record is that you're never quite sure who made the track. Different dinosaurs can make the same footprint impression. So there's some uncertainty as to who the cast of characters were in our early Jurassic dinosaur fauna.

ERIC: Now when you have a fossil footprint, can you get a good date of when the footprint was made?

MARK M: We're pretty sure about the age of the rocks. So it's right around two hundred million years is the age for the Portland formation that contains so many of the great footprint impressions. Unfortunately, dinosaur bone material has been much harder to find. It does appear, we know it's there, as sand casts and sometimes the actual bone material. For example, the material that led to the naming of our state dinosaur Podokesaurus holyokensis.

ERIC: That's right, we have an official state dinosaur here in Massachusetts. Tell us about that fossil specimen.

MARK M: Podokesaurus was found in 1910 within a mile of the Mount Holyoke campus by my predecessor there, Mignon Talbot. And it was a spectacular specimen, lacking its head, but with a lot of the post-cranial skeleton. Sadly I use the past tense 'was' because the specimen was destroyed in a fire at Mount Holyoke in 1917. A terrible loss for us.

MARK A: And it goes to show how rare that type of preservation is. I believe, correct me if I'm wrong, but that specimen, the exact origins of it, geologically, is not known because it was glacially deposited. Right?

MARK M: That's correct. It was a glacial float boulder.

ERIC: So not only was it that old, and the process of fossilization does all kinds of things that you have to untangle, but then the boulder that had the fossil was picked up by a glacier and just dragged across northern North America?

MARK M: That's correct. So the ultimate bedrock provenance of that specimen is somewhere to the north of where it was actually found. And we're working now to try to track down the exact bedrock source because there's certainly more dinosaurs in that same style of preservation, if we can find the layer.

ERIC: So our state dinosaur, if you saw it walking down the street today, what would it look like?

MARK M: Podokesaurus is a great example of the potential of paleo-artistic reconstruction. So we don't know what its head looks like. So that requires some speculation. I think if you were to see a live Podokesaurus, it would have a very bird vibe. And the first thing you would say is, well, that's a really strange looking partridge. And then you look more closely and, wait a minute, it's got teeth.

ERIC: Now, Mark A., you recently made a discovery of the type that we hear about all the time in science. You accidentally found something pretty awesome. And that brought you here to the Museum of Science to get a closer look at one of the fossils that has been in our collection for over 160 years. Can you tell us the story of the discovery first?

MARK A: Basically, there was a quarry in South Hadley & Granby, Massachusetts called Nash Dinosaur Tracks. And this was a very interesting family, the Nashes, that had their own dinosaur track quarry in their backyard, and it was a veritable business for the better part of 70 years. And it was founded by Carlton Nash, who was an amateur geologist, and he had three sons. One of them Kornell Nash, took over the family business in the late 90s. And he was, you know, actively quarrying tracks. And he did a lot of great scholarly work, but it was a commercial enterprise. And it was widely supported by the scholarly community in Western Mass, it wasn't necessarily seen as a bad thing, because people were at least not going and trying to find them themselves, say, on state land and things. So it was it was an outlet for people to be able to own their own piece of that prehistoric past. Kornell passed away in 2019. And I was close to the family. And I was interested in acquiring some of the specimens that Kornell had set aside. And outside their museum was a very large, about eight foot by four foot slab, of redstone sandstone, and it had all these dinosaur tracks on it. And I noticed immediately that it was probably from Connecticut by having gone to the Amherst Natural History Museum. And the preservation was like I'd never seen before. And so I basically inquired to buy it with the purpose of donating it to a museum just for the tracks alone. And when I got into my car, and mind you I had a sedan, so we cut the slab, you know, and I cut the section that had the best tracks, but that still amounted to a 350-pound block of red sandstone that was some six feet by three and a half feet long, you know? And my car was riding like a Cadillac, you know, trying to get out with it.

ERIC: Like a normal trip to IKEA.

MARK A: Yeah, no, just a regular buying trip. But I noticed that when I got home, it was dark. And the light in the back of the trunk cast a shadow over the slab. And I saw on the left hand margin of the slab, this kind of odd shape. It was slender, and it was kind of bent back like a bone and and even had like a condyle, like a contact point where one bone joins another bone. And I said, I'll be damned. I think that's a bone. And I had seen a replica of something comparable from that locality at the Nash Museum before, and that is MOS 2001.248, which is a really historical specimen. It was discovered by William Barton Rogers, who actually went on to found the Massachusetts Institute of Technology. His brother, Henry Darwin Rogers, was a geologist. They both had backgrounds as geologists, but back then, you know, if you were a polymath, you did everything. And he was a mathematician and engineer, but he found it outside of an old fort in Rhode Island. They were doing some reconstruction with brownstone. And brownstone from Connecticut was used widely in New York and Boston, you know, the old brown stone?

ERIC: Yeah, when I read brownstone, I was like, I bet that's where the buildings come from.

MARK A: Yeah. And in fact, the quarries in Connecticut, in Middletown and Portland, Connecticut, those were the sources of this material. And it was also the source of many of the fossil discoveries in New England. Basically, he saw in the building rubble a stone that had what he saw as bones. And it turned out that they were bones. And it was a significant find, because it showed the affinity with dinosaurs to birds at the time, and this was in 1865. And basically, that's the only other example of this type of fossil that we have.

MARK M: When Mark A brought this specimen to my attention, it was immediately clear that this was something important, because I was aware of your specimen, MOS 2001. And so this was a second example of this. But even more important, because it was a combination of both the bone pseudomorph plus tracks on the same slab. And that's just wonderful, because you've got them together on the same piece. You don't have to make any inferences if they're from the same bed, they are definitely from the same bed.

ERIC: Is it rare to find both at the same time on the same specimen?

MARK M: That is a unique specimen, correct me if I'm wrong, in the world?

MARK A: Yeah. When I had a hunch that it was a bone, I reached out to the person that I knew who was the person to kind of confirm or deny the discovery, Paul Olsen at Columbia. I was emailing him and I was eager to get a response. And he said, I think it is a bone. Because he had seen all these things. And he's a very talented person for the Newark super group from which the specimen hails. He also intimated that it was unique in the world, this association of tracks with this type of non-body fossil preservation.

MARK M: So a huge discovery and a real step forward as we try to learn more about the early Jurassic dinosaur fauna, which as I mentioned, is critical for the understanding of dinosaur evolution. And birds, of course.

ERIC: So super cool, super unique specimen. What were your conclusions? What could you learn from it?

MARK A: Well, I think the one of the takeaways is that for the longest time, the MOS specimen was singular. Is this some kind of amazing fluke of paleo environmental preservation? Well, the answer seems to be no. We found another one. So much of science is when you aren't looking for it, you're not finding it. But now that we know that there's at least a sample of two, we even have one that preserves tracks alongside it, that says something about how, perhaps, frequently it can preserve because tracks formed very frequently. So maybe there's a lot more bones out there. If we can get a bone that's more diagnostic. What we found was a was a metatarsal and then perhaps some ribs scattered in. So if we can find something like skull bones preserved this way, it might really help build a taxonomic definition of you know, what podokesaurus looked like here and what the New England dinosaurs look like, because it remains a mystery.

ERIC: So your new find, Mark A., the Nash specimen. It's also on public display now so folks can go see it?

MARK M: That's on display now publicly at the Bruce Museum in Greenwich, Connecticut. I wanted to make sure that it got back to its home state. So that's where it is, just outside of New York City.

ERIC: Mark, and Mark, thanks so much for talking to me all about New England fossils and some current research going on with them.

MARK A: Thank you, Eric. Thanks for having us.

MARK M: Thanks, Eric. A pleasure.

ERIC: Next time you're at the Museum of Science, be sure to visit the Blue Wing to see Dinosaurs: Modeling the Mesozoic, where you can see the MOS 2001 specimen on display. And while you're home, subscribe to our environmental newsletter Earthshift to keep up to date on the latest dino discoveries. Until next time, keep asking questions.

If you liked this episode, be sure to check out:

Why Did Dinosaurs Have Feathers?

Did T. rex Eat Stegosaurus?

What if the Dinosaurs Hadn't Gone Extinct?

Theme song by Destin Heilman

Various images of fossils found in Massachusetts.