How Often Do You Brush a Triceratops Fossil's Teeth?

Taking care of a 65 million-year-old Triceratops fossil is a delicate task. We ask Katie from our Collections department how, and how often, it gets cleaned in this Pulsar podcast brought to you by #MOSatHome. 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

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ERIC: From the Museum of Science in Boston, this is Pulsar, a podcast where we answer our favorite visitor questions. I'm your host, Eric. And recently, we posted a video on the museum's social media of our collections staff cleaning our 66 million year old triceratops fossil, Cliff.. And someone asked: how often do you need to do that? So I thought it would be the perfect opportunity to chat with Katie, our Assistant Curator, about the cleaning routine for our colossal fossil. Katie, thanks for joining me.

KATIE: Thank you for having me.

ERIC: So this video is so cool. You're literally brushing off a real triceratops fossil. How often do you need to do that?

KATIE: So with Cliff, we need to clean him about every three months. He can go a little longer, he doesn't need as much cleaning as some other artifacts.

ERIC: So is it just, same as everything else, dust building up? Is there anything special going on with a fossil?

KATIE: So with a fossil, no, it's mostly dust building up. But when we clean, we take that time to actually examine all the parts of the fossil to make sure if there are new cracks that we haven't seen before, anything that looks suspicious, he doesn't really have to deal with pests at all. So that one, we can take a break with.

ERIC: Termites and moths not interested in fossils?

KATIE: No, they don't like Cliff.

ERIC: So the tools that you were using in the video, they look fairly normal. Is it just kind of like small brushes and a vacuum cleaner?

KATIE: Yep, just a small brush and a vacuum cleaner, a soft bristled brush. Nothing too high-tech at all.

ERIC: So you have to do it every once in a while to make sure that it, you know, maintains its integrity and everything. But you don't want to do it too much, right?

KATIE: Correct. So we clean the dust off because dust can be harmful actually, because dust has skin cells in there, kind of, air pollutants as well. So that can damage the fossil. But then actually, if you do it too much, your mechanical movements can actually damage the fossil as well. So that's why we only do it every three months.

ERIC: So it's kind of crazy to think that this fossil sat under the ground for 66 million years, still looks this good, and we have to be really careful with exactly how often that we clean it. Not too often because we don't want to damage it, but not...not very often because that wouldn't be great either.

KATIE: Yeah, it's funny to think and when you think about archaeologists, they use dental picks and tools to take the fossil out of the ground. And here we are just being so careful to make sure Cliff lasts another 60 million years or whatnot.

ERIC: Yeah, hopefully. This is a huge job. I mean, in the video, you have a ladder because the triceratops is massive, it's the size of a small elephant. Is it a big job? Does it take all day?

KATIE: It actually doesn't take all day, it only takes about two hours. That actually seems like a lot for cleaning. But so we spread it out in the mornings before the museum opens, just to be thoughtful to our visitors. We don't want dust flying around everywhere. And usually I split it between two days. So I'll do half one day, half the other day. And what you didn't see in that video is usually at the end, I climb onto the fossil base and I'm standing underneath like in the rib cage area to get the inside of the ribs.

ERIC: So just a couple hours to clean that whole thing. Do you still have to take your time and kind of like focus? I'm sure you're not, like, listening to music while you're doing it. You said you were inspecting it as you go.

KATIE: Yeah, no, I'm not listening to any music, just the the loud hum of the vacuum cleaner.

ERIC: Are there any parts that are more or less delicate than others? I mean, you've got tiny little bones, some of the bones ware like the size of a human, there's the horns. Is it just kind of all the same job? Or do you need to change your technique from the beak to the frill?

KATIE: I'd say it's mostly the same technique the entire time, except for when you notice possible cracks. Cliff is actually painted. So there might be cracks in the paint or cracks in the fossil itself. So around those areas, you want to be very careful so you don't do anything else. Usually I just avoid those areas.

ERIC: What's the protocol if you find, like, a new crack or something? Is there, like, a dino team rescue that you can call?

KATIE: I wish. No, I actually just take a picture of it. Look at my condition report that I have for Cliff. I actually just updated it while we were closed to the public. And make sure it's not new, it's not getting bigger. I even note, like, the size too, just so we can keep an eye on it.

ERIC: So how is it holding up? Is it in pretty good condition? Is it still really great? Is it, you know, more cracks every time you look at it?

KATIE: I'd say it's in pretty good condition. I haven't noticed any changes, which is great, especially being closed for all that time and not getting the visitor attention that he so really deserves.

ERIC: Yeah, it's great to be back open again and see the kids come up to it and just look at this gigantic fossil. So it's awesome that we can try to make it last as long as we can so that as many people can enjoy it. Is it, maybe, the most delicate thing you have to take care of out of all the collections? I mean, I know we have a lot of things that are extinct mounted, all that kind of stuff. But is this the one that you're thinking in your mind the most, like, I really have to be careful while I'm cleaning this, this is irreplaceable?

KATIE: Oh, that's a really good question. For the routine cleaning Cliff is pretty delicate, but still really sturdy because the fossils are rocks, basically. The part about Cliff that makes me the most nervous is the rib cage area. They like to sway a little bit as you clean them. So I'm very careful around there. The tail bones as well, those are delicate too. But I'd actually say the craziest thing I've ever had to move or clean is the Blaschka glass models, which if you ever want to talk about that we can totally talk.

ERIC: Oh, that'd be a whole other episode. Yeah, any of those things that are glass models, they're so complex and yeah, I imagine it's the same thing. You have to maintain them, you have to clean them, dust can't build up, but they're irreplaceable. You can't just go to a store and get another one.


ERIC: So what's it like to actually be inside of the triceratops looking around at the rib cage knowing that it's super delicate and you have to pay attention to but you get that, like, goosebumps feeling of: I'm in a triceratops right now?

KATIE: Oh definitely. My favorite part is actually cleaning the inside of cliffs mouth. I feel like a dinosaur dentist.

ERIC: So it really is just kind of, like, brushing the teeth.

KATIE: Yeah, basically.

ERIC: Do you have like a comically large toothbrush? Or is it more like a paintbrush?

KATIE: No, the same brush I was using in that video for the whole thing.

ERIC: So one kind of big, fuzzy brush. Not anything special? Not any, like, you don't have to go to the dinosaur store to buy special tools.

KATIE: No, but if you know a dinosaur store, let me know.

ERIC: So same as archaeologists, you have to just be delicate while you're taking it out of the ground, super delicate while you ship it, and then examine it and then even after you mount it. Is it your favorite thing to clean at the museum?

KATIE: Oh yeah, Cliff doesn't complain. He is very quiet and appreciates the cleaning, I hope, and not as crazy to clean as taxidermy.

ERIC: Oh, that's a whole other episode.

KATIE: Oh yeah.

ERIC: Well, Katie, thanks so much for telling us all about Cliff's upkeep routine. I'm sure we'll have more visitor questions about all of our collections in the future.

KATIE: Thank you.

ERIC: You can visit Cliff the triceratops in person in our Blue Wing at our Colossal Fossil exhibit. And for more on the extinction of the dinosaurs from home you can check out Episode 52 of this podcast, What If the Dinosaurs Hadn't Gone Extinct?, as well as our Sparks of Science video Did the Dinosaurs Disappear? Until next time, keep asking questions.

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