Victoria:
Our guest this week is Dr. Karen Chin. She is an associate professor and curator of paleontology at the university of Colorado Boulder. Most of her research focuses on reconstructing Mesozoic ecosystems, which not only include dinosaurs, but also snails, beetles, worms, fungi, and other less popular organisms that lived with the Mesozoic dinosaurs.
Dr. Chin: is best known for her research on fossilized dinosaur dung. This unusual line of inquiry provides information about ancient animals that is unavailable from other types of fossils.
Dr. Chin’s work has been highlighted in various media venues, such as National Geographic, Discover, Nautilus, the Washington Post, and the Nova television show.
This week’s questions were submitted by students at Bromwell elementary in Denver, Colorado, and by the listeners through emails and on social media.
Dr. Chin:, thank you so much for talking to us today.
Dr. Chin:
It’s a pleasure to be here, Vikki.
Victoria:
(Mark: What does fossilized dinosaur poop look like? Does it look like poop?)
We’ve got a lot of good questions about dinosaur dung from the students. This first question is from Mark. What does fossilized dinosaur poop look like? Does it look like poop?
Dr. Chin:
That’s a good question to start off this session. I’d say that fossilized poop, or we call fossilized poop coprolites. Fossilized poop from medium-sized animals, like say dog-sized animals, can indeed look very much like modern poop, although it may be different colors: it can be white, black, red, depending on the minerals in the rock. But if you’re looking at fossilized dinosaur poops, since most dinosaurs, or I shouldn’t say most, many dinosaurs were very large. If you’re looking at poop from very large dinosaurs, that often doesn’t look at all like poop because it is so large that it didn’t hold the shape that originally had and can be broken up into many pieces. So it’s easy to recognize fossilized feces from dog-size animals, but dinosaurs it’s a little more difficult.
Victoria:
(Milo: Did dinosaurs just poop anywhere, or did they go to special spots, like my dog in our backyard?)
Okay. Here’s a good follow-up question from Milo. Did dinosaurs just poop anywhere, or did they go to special spots, like my dog and our backyard?
Dr. Chin:
Okay. I suspect that most dinosaurs pooped just about anywhere they felt like it, like most living animals. But poop, our feces, can carry some dangerous parasites can make animals sick. So most animals naturally try to avoid their own poop. For example, when horses live in a corral, where they’re penned up, and they can’t get away from their poop. They usually tend to put it in one place, so they don’t keep running into it. So this means that if dinosaurs lived in a small area for an extended period of time, such as maybe when they were laying eggs, they probably left their poop in places that would not contaminate their food.
Victoria:
Hmm. That’s interesting. I never knew that about horses.
Dr. Chin:
Yes. Yes. If you have wild horses, they will poop anywhere. But if you pen them up, they do have different pooping behavior.
Victoria:
(Gabi: Did other animals ever eat dinosaur poop? (My dog loves to eat kitty litter…))
This next question is from Gabi. Did other animals ever eat dinosaur poop? Like my dog loves to eat kitty litter.
Dr. Chin:
Well, we do have fossil evidence that dung beetles and snails ate dinosaur poop. And I wouldn’t be surprised if other animals, maybe even small mammals, ate dinosaur poop as well. It can sound a little bit gross to some people, but remember that for some animals, dinosaur poop is their preferred food. So, it’s not gross to them and they think it’s just as good as eating a hamburger to us.
Victoria:
(Finn: Could you tell what other dinosaurs were eaten by carnivorous dinosaurs from the poop?)
Finn wants to know, could you tell what other dinosaurs were eaten by carnivorous dinosaurs from the poop?
Dr. Chin:
In most cases, we can’t tell the exact food from the material in a dinosaur poop. If there are pieces of bone, maybe if there’s a very distinctive piece of bone or distinctive tooth, we could tell who the victim was. But In most cases, we can only say, okay, this looks like dinosaur bone, or maybe this is dinosaur bone from a certain broad group of dinosaurs, like plant eaters. But most of the time, at this point, we just can’t tell.
Victoria:
(Jennie: Is a pile of poop unique to one dinosaur, or is it all kind of the same? Can you tell if one dinosaur pooped in one place and then the same one pooped in another place?)
All right. Here’s another question about things you can or can’t tell from looking at poop. Jennie wants to know, is a pile of poop unique to one dinosaur, or is it kind of all the same? Can you tell if one dinosaur pooped in one place, and then the same dinosaur pooped in another place?
Dr. Chin:
Okay, well, we can recognize general types of dinosaur poop. So, if we see some, we can say, oh, that’s poop from a carnivorous dinosaur; or in other cases, well, that’s poop from a dinosaur that ate leaves. But those are just general observations that we can make. If we see one pile of poop, and we say, well, this is a poop from say a carnivorous dinosaur. And then we see another pile of poop. We can’t tell if those two different piles of poop were made by one dinosaur because we don’t know how much time passed in between when the two piles of poop were deposited, and we don’t know if another dinosaur came along and poop near the first one. So we can’t tell piles of poop from individual dinosaurs, but we can recognize different types of dinosaur feces.
Victoria:
(Carla: What did dinosaur poop smell like?)
That makes sense. Here’s a series of some funny questions. This first one is from Carla. What did dinosaur poop smell like?
Dr. Chin:
Well, we don’t know exactly what dinosaur poop smelled like, but I think it probably smelled a lot like the poop of living animals that ate similar things. For example, if we smelled lion poop, this is hypothetical, okay. If we smelled lion poop, that might smell a little bit similar to maybe T-Rex poop, who was also eating other animals. And if we had a poop from a plant eating dinosaur, well, that might smell a little bit similar to elephant dung when an elephant was eating plant tissues.
Victoria:
Like sort of, if the students go to a zoo, and they smell poop at the lion enclosure or the elephant enclosure.
Dr. Chin:
Exactly. Exactly.
Victoria:
(Margaret: Did dinosaurs hate the smell of their own poop?)
All right. This is a follow-up question to that from Margaret. Did dinosaurs hate the smell of their own poop?
Dr. Chin:
Well, that’s an interesting question. I don’t know if we could say they hated the smell of their own poop. But since poop can carry the parasites we talk to and make animals sick, most animals try to avoid our own poop, and that includes humans. And I think one of the functions of bad smelling poop is that it does help us avoid it. So I think most animals, including dinosaurs, including living animals and extinct animals, like dinosaurs, probably would have tried to avoid their own poop. And that’s probably because they didn’t like the smell of it, but I don’t know if I’d say they hated it.
Victoria:
Yeah. It’s hard to tell emotions, like hate, from the fossil record.
Dr. Chin:
Exactly. On the other hand, some animals do like to smell poop of other animals because they can get certain cues, things that we can’t tell, behavioral cues or the state of the physiology of the animal that left the poop. So they do smell it. So I don’t think they hated it, but I think in general they would try to avoid it.
Victoria:
(Meredith: How big could the biggest piles of dino poop get?)
Okay. This is a question from Meredith. How big could the piles of dinosaur poop get?
Dr. Chin:
The biggest piles of dinosaur poop from one animal that deposited the poop at one particular time, in terms of the fossils we found, the biggest ones we found are about seven liters in volume. And I’d say that it’s much bigger than a basketball. That’s pretty big. That’s a big pile of poop. But I suspect that in the future, it is quite possible that we will find even larger piles of poop from gigantic dinosaurs, like apatosaurus and diplodocus, we just haven’t found bigger piles of poop yet. Possibly because they didn’t stay together after they were deposited, or it could also be that we just don’t recognize them.
Victoria:
(Barbara: Does their poop show that their digestive systems were basically a lot like modern animals?)
All right. Barbara wants to know, does their poop show that their digestive systems were basically a lot like modern animals?
Dr. Chin:
From what we can tell, it does look like feces from ancient animals looks a lot like what we see in feces of modern animals. We can’t always tell who produced a fossilized poop, so we may not know which animal we should link it with. And it’s true that even in modern animals, some animals digest their food very well and other animals don’t digest their food very well. So, when we study fossilized poop, it looks like we have the same range of digestive processes that were happening in ancient animals. And in most cases, we usually hypothesize that this means that their digestive systems were pretty similar.
Victoria:
(Jack: Are there undigested things in the poop?)
This is a good follow-up question speaking of digestive processes. Jack wants to know, are there undigested things in the poop?
Dr. Chin:
Yes, there are, Jack. Yes, there are undigested, what I would call dietary residues, I find in fossilized feces. There may be bits of bone, or bits of leaves, or bits of shell that we recognize. And those do give us great clues as to what things that ancient animal ate.
Victoria:
(Teresa: Have you found any dinosaur vomit?)
Alright, speaking of waste products of dinosaurs, Teresa wants to know, have you found any dinosaur vomit?
Dr. Chin:
Okay. I don’t think I have ever found any dinosaur vomit. But, other paleontologists have found what appears to be fossilized vomit.
In some cases, as with coprolites, you don’t know exactly who produced it: it could have been from dinosaurs, or it could have been from other animals. But when you think about modern animals or living animals, especially living dinosaurs like birds, there are some birds that intentionally vomit things, and that includes birds of prey, like eagles and hawks. And that’s because they eat things, and they don’t want to carry around all of that, the stuff they can’t digest, like fur and bones. And so they eat things and they vomit out the things that are not digestible.
And it looks like some of the fossils that people have been finding, even a recent scientific paper just published within the last month or two, people are beginning to recognize fossilize vomit in the fossil record.
When we say vomit, usually we think about vomit when we’re sick, right. But in many cases for animals, vomit, to actually regurgitate their food or the undigestible parts of their food, is very natural.
Victoria:
Hmm, that makes sense, like my cat will vomit hairballs. He doesn’t want to digest his fur.
Dr. Chin:
Right? Yes.
Victoria:
(Addy: How can you tell fossilized poop from regular fossils or even rocks?)
This next question is from Addy. How can you tell fossilized poop from regular fossils or even rocks?
Dr. Chin:
That is a great question, Addy. Lots of people show me things that have a poop shape, show me rocks that have a poop shape, and they think, oh, well, is that a coprolite? And I probably have an easier time telling fossilized poop from regular rocks than most people, but sometimes even I can’t tell. And that’s because there are many poop-shaped rocks. And so you have to say, well, what are the characteristics that actually defined fossilized feces. And so I look at several different criteria.
If they have lots of chopped up bits of organic material in them that looks like it was from eating, if they were dietary residues, that indicates that could be fossil feces, if there’s no other way that you would get all of those organic chopped up bits accumulated into one small mass.
I sometimes also look at the chemistry, because the chemistry of the diet is sometimes reflected, or actually I should say, is usually reflected in the diet and fossilized feces.
I look for shape, but shape is not always a great feature to look for. It may be with those medium size animals, I talked about like dog-size animals. But if you’re looking at giant feces, that can be all broken up. and they may not have any distinctive shape at all.
And sometimes we look for a distinctive burrow. Because as we already talked about, some animals do like to feed on faces, and they make distinctive burrows within feces.
So I examined all of those different characteristics to try to tell fossilized poop from rocks that have nothing to do with the feces at all.
Victoria:
That sounds like fun, sort of like a mystery that you’re solving.
Dr. Chin:
It is a mystery. Yes. And sometimes even after studying some specimens, I may still think I’m not quite sure.
Victoria:
Tricky ones.
Dr. Chin:
Yes.
Victoria:
(James: Have you had to study how lizards poop to learn about dino poop?)
Okay. This next question is from James. Have you ever had to study how lizards poop to learn about dino poop?
Dr. Chin:
Well, actually I have, it’s still sound funny, but I have read about and looked at pictures of all kinds of poop to help me understand fossilized poop. But most of the poop I look at or read about are from much larger animals than lizards because I do study many dinosaur feces. If I was near Indonesia so that I could look at feces from great big lizards, like the Komodo dragon, that would probably be very useful. But most of the time I read about other kinds of animal poop in order to learn about dinosaur poop.
Victoria:
(Jamie: Why would you look for fossilized poop instead of things like teeth and claws?)
That makes sense. This next question is from Jamie. Why would you look for fossilized poop instead of things like teeth and claws?
Dr. Chin:
Well, there are lots of paleontologists that study bones, teeth, and claws, and you can tell a lot about ancient animals. You can tell about, when you look at their bones, you can tell about what they look like, how the kinds of muscles, whether they had really robust muscles that they might’ve used, and whether they were meat eaters or carnivores, you can tell a lot by looking at the skeleton elements of ancient animals.
But there are things that you can’t tell by looking at the bones, and I like to study trace fossils, which are our fossils that tell you more about the behavior and activity of animals. And that includes things like fossilized poop or coprolites, it includes fossil burrows and fossil tracks. And sometimes trace fossils are more difficult to study because we don’t always know who made the track, or the burrows, or the poop. But they do tell us different things about ancient life.
And we need to study both of the bones and the skeletons of ancient animals and plants. And there are trace fossils in order to get a more complete picture. Well, we’ll never have a complete picture, but in order to get a better picture of what ancient ecosystems were like.
And I just particularly am interested in what animals ate. So if I’m interested in animals ate, what better place to look then fossil poop.
Victoria:
(Sarah: Do museums keep a lot of dinosaur poop in their storage?)
But it’s fun. Sarah wants to know. Do museums keep a lot of dinosaur poop in their storage?
Dr. Chin:
Well, actually dinosaur poop is pretty rare. There are lots of fossil feces from a lot of different animals, say fish, or mammals, or other animals that people have found. But poop that was definitely produced by a dinosaur is pretty rare. So I would say that many museums often have coprolites or fossil poop in their storage, but not too many have definite dinosaur poop.
Victoria:
(Marcello: What were snails, beetles, worms, fungi like during the time of the dinosaurs?)
Okay. Switching gears a little bit. Marcello wants to know what were snails, beetles, worms, and fungi like during the time of the dinosaurs?
Dr. Chin:
We are still trying to learn about how the little guys like invertebrates, like snails, beetles, worms that you’re talking about, that were living with the dinosaurs. We are beginning to learn more about them. And surprisingly, what we’ve learned so far is that many of those animals were quite similar, as far as we can tell, to animals that are living today. We have found interesting burrows produced by dung beetles in dinosaur dung. But they often are similar to the kinds of tunnels produced by living beetles. We have found snails in dinosaur dung that were actually breeding in dinosaur dung, and they look a lot like some of the snails we have living today. Fungi, you mentioned fungi, we have evidence that some of the dinosaurs were eating wood that was already rotted by a kind of fungi called white rot fungi. And we have lots of different types of white rot fungi living today.
So we haven’t found any organisms that have been colonizing the dinosaur dung that we are quite surprised about, but we have been surprised sometimes about what the dinosaurs actually ate. For example, we were surprised to learn that some herbivorous dinosaurs actually intentionally ate rotted wood. And some also appeared to intentionally eat some kind of crustaceans, possibly crabs. So some of their dietary choices, their food choices, are surprising. But we’re still trying to figure out exactly what the different kinds of animals and plants that lived with dinosaurs were like.
Victoria:
That is very cool. All right. We’re going to switch gears a little bit. The next set of questions, instead of being about dinosaurs or dinosaur poop, are all about you and your career.
Dr. Chin:
Okay.
Victoria:
(Bailey: What is your favorite part about being a scientist?)
So this first one is from Bailey. What is your favorite part about being a scientist?
Dr. Chin:
My absolutely favorite thing about being a scientist is doing research. I love doing research and discovering new things that nobody ever knew before I did my work.
Victoria:
(William: How old were you when you knew you wanted to be a scientist?)
That’s fun. All right. William wants to know how old were you when you knew you wanted to be a scientist?
Dr. Chin:
Okay. I always loved studying animals and plants and science when I was your age, you guys are in the fourth grade. I did like to go out and look for insects and learn about the different names of plants and animals. But I don’t really think, I thought about the possibility that I could be a research scientist and make new discoveries until I was actually in my twenties.
Victoria:
So you’ve got plenty of time to figure out what you want to do.
Dr. Chin:
Yes. You have lots of time. I think you want to go out and learn about lots of different things. Some people like science, some people like language, some people like history, you have to experience so many different things before you find what it is that you want to do for the rest of your life. And even then, you might change.
Victoria:
(Tatiana: What is your favorite book on paleontology?)
All right, this next question is from Tatiana. What is your favorite book on paleontology?
Dr. Chin:
Oh, Tatiana. That’s an almost impossible question. I don’t think I have a favorite paleo book, but I love books. I love all kinds of paleo books. I have zillions of books on dinosaurs, books on invertebrate fossils, books on trace fossils, books that study how fossils were preserved, all kinds of books. I also like and collect books that describe living animals and plants, because in order to learn about ancient animals and plants, you have to study the ones that are living today.
Victoria:
(Billy: What it is like to be on TV?)
All right. Billy wants to know, what is it like to be on TV?
Dr. Chin:
Being on TV program is kind of funny because they may have to do several takes. They will film you, and then they’ll decide, okay, let’s try that again. Or else I will start talking, and then I will make a mistake, I’ll trip over my tongue, and I’ll say something wrong, and we have to keep doing it again.
And it is funny too. It is funny to think that you’ve got a camera on you. So it’s kind of fun, but it is kind of unusual. It’s not like real life. And then you see the finished product and you think, oh, I should have done this, or I should’ve said that, I wish I had done this better.
Victoria:
Oh, man. Is it easier being on a podcast than it is being on TV?
Dr. Chin:
Yes, it is easier being on a podcast. I don’t have to worry about if my hair is sticking straight up.
Victoria:
(Lea: What is the hardest thing about what you do?)
Alright. Lea wants to know what is the hardest thing about what you do?
Dr. Chin:
I think the hardest thing about my job is trying to keep up with all of the many different kinds of responsibilities that I have, teaching, and making lectures, and grading papers, and working with students, doing research. And that doing research includes spending time in the lab, maybe I’m studying things under a microscope, maybe I’m preparing fossils so that I have to do certain analyses on them. My job as a museum curator, where I take care of fossils, and I have to help keep up with all of the paperwork and documentation that is necessary in museums. And then I also answer a lot of questions about fossils. So there’s so many different things. That is the hardest thing about my job, is trying to get everything done.
Victoria:
(Daniel: What is your favorite snack?)
This is a fun follow-up question from Daniel. What is your favorite snack?
Dr. Chin:
Okay, Daniel, I love this question cause it’s easy. Popcorn. Popcorn is my favorite snack.
Victoria:
(Molly: What is your favorite museum that you’ve worked at?)
Okay. Molly wants to know what is your favorite museum that you’ve worked at?
Dr. Chin:
Okay. I’m going to have to give you two answers for this question. I certainly love the University of Colorado Museum of Natural History where I work right now, but I also really enjoyed working at the Museum of the Rockies in Bozeman, Montana. There are different kinds of museums. But I just think museums are wonderful. And these are two of my favorite ones.
Victoria:
(Kobi: What is your favorite dead animal and what is your favorite living animal?)
Okay. This question, another favorite question, is from Kobi. What is your favorite dead animal? And what is your favorite living animal?
Dr. Chin:
All right. You guys asked really hard questions. There are too many animals to choose from, so I’m going to give you…
Okay, extinct animals. I liked the herbivorous dinosaurs, that would include duck-billed dinosaurs, but also the giant sauropods, like apatosaurus and diplodocus.
Extent animals, okay. Probably my favorite are whales. I know that’s really different from dinosaurs, but I just love whales. And I also love some living dinosaurs, or actually many living dinosaurs, like puffins, arctic birds that are just so funny-looking and cute.
Victoria:
They are cute.
Dr. Chin:
And I also love other dinosaurs like penguins.
Victoria:
(Sheamus: Who is your favorite scientist dead or alive?)
Also cute. Yes. Okay. One more favorite question. This is from Sheamus. Who is your favorite scientist? Dead or alive?
Dr. Chin:
Another, another challenging question. There are so many cool scientists, but I think I’d have to say that my favorite scientist of all time is Charles Darwin. And that’s because he taught us so much about life, and evolution, and also about life through time.
I’ll also have to add that my father was also one of my favorite scientists. He was a material scientist, so he didn’t study the kinds of things that I do, but I thought he was pretty cool.
Victoria:
(Ciara: What else do you do as a professor besides look at fossil poop?)
Wow, okay. Ciara wants to know, you’ve touched on this a little bit, but if there’s anything you want to add, what else do you do as a professor besides look at fossil poop.
Dr. Chin:
Yes. We spend a lot of time preparing lectures, and teaching, and grading, and doing curation fossil or specimen curation in museums, which means that we may be cataloging certain specimens or deciding which kinds of specimens we keep.
When I get to go on the field, I spend a lot of time looking for fossil, and then cataloging those, studying those.
And I do spend a lot of time in the lab, and yes, much of the time I’m looking at fossil poop, but I could be looking at other kinds of things also.
And then I do answer questions from people, and I go to a lot of committee meetings.
Victoria:
(Karina: What do you do after you come home from work?)
All right. Well, this is our last question, and it kind of fits perfectly with what you do at the end of the day. Karina wants to know what do you do after you come home from work?
Dr. Chin:
Okay. Well, I suppose it depends on what time of year it is. If it’s in the summer, I like to go out and look at the garden with my husband. We have a really, well, I think it’s a nice garden. And then I really liked to relax by during dinner, and usually watch a little TV. And then I usually like to go back and do some more work before I go to bed.
Victoria:
Sounds like a relaxing evening.
Dr. Chin:
Yes.
Victoria:
All right. Well, that is all of our questions. Thank you so much.
Dr. Chin:
Thank you so much for asking me to participate. All of the questions were good. Some were fun. Some were insightful. I’m just glad that you guys are interested in science, and all of you kids out there, not just these kids in this class, but all of you keep asking questions about how the world works.
Victoria:
That is so important.
Dr. Chin:
I think so.
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