MR. KOJO NNAMDIFor most of us, the Potomac is just another scenic feature in a region rich in American history. But for paleontologists, the river and its shores are scientific pay dirt. Millions of years before the nation's capital was founded, massive beasts lived and died in this region, and their remains are surfacing just below our feet. From 15-million-year-old whales to sharks, dolphins and even dinosaurs, ancient history is coming back to life with the help of pickaxes and chisels.

MR. KOJO NNAMDIThere are fossil finds that are important enough to get coveted spots in the Smithsonian's display cases. And while we may not have any T-rex's to donate to the museum, local fossils are contributing to the body of knowledge scientists are constructing about how this area looked tens of millions of years ago. So what are paleontologists digging up? What challenges are they encountering, and what fossils can you find in this area?

MR. KOJO NNAMDIHere to help us figure that out is Matthew Carrano. He is curator of Dinosauria at the Smithsonian National Museum of Natural History. Matt, good to see you again. Thanks for joining us.

MR. MATTHEW CARRANOGood to be back. Thanks for having me.

NNAMDIAlso in studio with us is Dave Hacker, amateur paleontologist and fossil hunter. He's also a volunteer at the Dinosaur Park in Laurel, Md. Dave, thank you for joining us.

MR. DAVE HACKERGood to be here.

NNAMDIAnd joining us by phone from Martinsville, Va., is Alton Dooley. He is curator of paleontology at the Virginia Museum of Natural History. Alton, thank you for joining us.

MR. ALTON DOOLEYThanks for having me.

NNAMDIFor those of you enthusiasts who would like to join the conversation or those of you who would just like to find out what the heck we're talking about, call us at 800-433-8850. Are you a fossil hunter? What interesting finds are in your collection? 800-433-8850. You can send email to kojo@wamu.org. Matthew, we're lucky you're in this town to talk to us because I hear you've been spending a lot of time out in the North Dakota badlands digging for fossils. Put on your headphones so that we can all make sure that we hear Alton. Why are you out in the North Dakota badlands, and what are you finding?

CARRANOWell, at the Smithsonian, most of us go out once or twice a year to collect fossils, bring them back to the national collections. My research actually focuses on the environments and ecosystems that dinosaurs were part of. And so I collect what are called microvertebrate fossils, and these are collections of thousands of fairly small fossils associated with dinosaur skeletons that represent all of the other organisms in the environment, so amphibians and reptiles and birds and crocodiles. And that allows us to sort of flesh out a much more detailed picture of the places in the ecologies in which dinosaurs lived.

NNAMDIThe Natural History Museum has more than 46 million fossils. Why couldn't you just look in the storage vault for some of the fossils you need for the putting dinosaurs in their place exhibit?

CARRANOWell, we start with that, certainly, but the collections that we already have only get us so far. And in fact, most of the time working in the collections, we generate new questions. So looking at the collections we already have from Maryland, for example, we could tell that there was something really of interest here, but our collection was relatively small. So we were really keenly interested in augmenting that collection, and the same went for what we have from, say, Montana and North Dakota.

NNAMDIThis dinosaur exhibit is kind of a teaser, if you will, for a huge renovation that the museum is doing for 2019. Tell us about the work you'll be doing on the museum's dinosaur fossils over the next five years to get ready for this?

CARRANOYeah. It's a pretty enormous undertaking. It's actually the largest exhibit renovation the museum has ever done. And we will be dismantling the entire paleontology exhibit. Starting this fall through April, it will be closed until 2019. And when we open it again, it will be completely new. So we're taking down everything, every single exhibit, every single fossil. So the exhibit will be completely reorganized and reimagined and reflect the kinds of things we think are important about the ancient world now as opposed to what we thought 20 or 30 years ago.

NNAMDISounds fascinating. If you're just joining us and you'd like to join the conversation, call us at 800-433-8850. Where do you like to look for fossils? You can send email to kojo@wamu.org or send us a tweet, @kojoshow. Alton, we don't need to go out to the badlands to find big fossils. There's a lot going on closer to home, including in Virginia, where you recently excavated a whale on the York River that was once up to 50 feet long. What's the story behind this huge fossil?

DOOLEYWell, that's right. There are a lot of fossils in Virginia. Virginia's got a history of paleontology going back several hundred years. This whale that we collected recently on the York River came from the naval station on the York River. It was about a third of the skeleton and from a very large whale. We've recovered flippers, ribs, a lot the vertebra. And it comes from a period of time in Virginia's history where we don't have a good record of fossil whales.

DOOLEYVirginia has a lot of fossil whales, but they don't all occur during the same time periods. This one was about seven million years old, and it's gonna help us fill in the gap in our knowledge of how whales were evolving and what they were -- what their lifestyles were along the Virginia coast over the last 20 million years or so.

NNAMDIHow do you protect a find like this when you're not able to dig, and are there challenges locating it again after a season or more passes?

DOOLEYThere are in some cases, particularly with the variable climate that we have in Virginia. And when we're working near the coast, we have sometimes issues with tides and storms and things like that. In most cases, when we find a skeleton, one of the rivers in Virginia, we try to excavate it as rapidly as possible because they tend not to survive very long. In this case, we actually had to leave the whale for several months because it was found just before the winter, and the weather was too bad for us to excavate it.

DOOLEYSo we put a protective layer of a burlap and plaster over the whale onsite and left it there, re-buried it and left it there for a few months, and then we went back last spring and excavated it.

NNAMDIDave Hacker, you're an amateur paleontologist and fossil hunter, not a collector, which we'd like to make clear, and it's a hobby that you've been pursuing for decades. The last time we talked about dinosaurs on this show was in 2010, a little less than a year after the Dinosaur Park in Laurel, Md., opened. I know you spend a lot of time at that Dinosaur Park. Tell us a little bit about the site and what you've been finding there.

HACKERSo the Dinosaur Park is a early cretaceous site, so fossils were deposited there about 110 million years ago. So this is dinosaur times. It's a terrestrial site, which means that it preserves fossils from things that were living on the land or in the freshwater. So it's not a marine site like one that would have whales or things that lived in the ocean, which means that the conditions are much harder to -- are much more rare actually to get that sort of a situation. And so we have this site.

HACKERIt's the one site that's really producing good fossils that we know of in this area, and so it's important to protect it. And it became a park, as you said 2009 -- late 2009. And so what we do is we watch the exposed site for new fossils washing out. And we invite the public in twice a month, first and third Saturday of the month from 12 to four. And so I'm involved both in those public programs and in also just watching to see what comes out and looking for new fossils.

HACKERAnd when we do find new things, we assess them to see if they're -- is it an important fossil or is it sort of a typical fossil for the site. And pretty much every new fossil that comes out goes into a collection, either the park's own collection or into the Smithsonian's collections, depending on what it is.

NNAMDISo you have found fossils that can make Matthew say respect, fossils that are worthy of display cases at the Smithsonian.

HACKERYeah. And it's not all about display cases. Sometimes it's about display cases, and really more importantly, I think is to fill in the picture of what was going on here at that time and then fill in pieces of the scientific puzzle.

NNAMDIOn to the telephones. We'll start with Maureen in Arlington, Va. Maureen, you're on the air. Go ahead, please.

MAUREENYeah, hi. Once upon a time, about 32 years ago, I was a graduate student in geology at Cal State, Northridge and Dick Squires was my professor in paleontology. Perhaps the panelists on your show know of Dick. He did quite a bit of a world-renowned work in paleontology. But on a couple of expeditions, three or four-day weekends, we went into the mountains of Ojai, Calif., which if I recall correctly was Precambrian.

MAUREENAnd I walked away with a -- after a three-day weekend, walked away with quite a nice little collection of fossils that included (unintelligible) I had a regularis and an irregularis. I had a couple of fossilized bivalves. And I don't remember what else I had. I carried that collection with me for years and years and years. I packed it up with my books, told the movers to always be careful with it.

MAUREENAnd finally, last year, I gave it away, out of the goodness of my heart, to a geologist at the National Science Foundation, and he was quite appreciative of it. But my point is is that fossil collecting is a really keen way to fine-tune your mind and your sight for picking out details as you're hiking or walking along areas. And I would be curious as to whether members of your panel can discuss anything about the Precambrian existence up there in Ojai, Calif., if you've ever been there yourselves.

NNAMDIWell, you asked a couple of questions. Dave Hacker, I'll put the first question to you, and that is how she said -- how Maureen says it helps to refine the mind.

HACKEROK. I agree with that statement, (laugh) I would say...

NNAMDIWhat got you involved?

HACKEROK. What got me involved actually and it really wasn't decades ago. It was more like eight or nine years ago that I really got involved, always was interested in fossils. But we actually signed my kids up for a dinosaur camp, live with dinosaur camp, and of course, I was the one that got completely hooked, (laugh) not my kids. And so when I would start fossil hunting -- I had the same experience. It wasn't even really about actually finding the fossils. It was about looking, and it was about being out there by myself looking.

HACKERAnd so it's sort of a -- almost like meditating, sort of being able to focus on little things on the ground and noticing what's different than all the other rocks around. And I think most fossil hunters, when they start out, won't be finding much.

HACKERAnd then when you start being able to pick out that thing that's different, that tooth that's lying on the ground among the rocks and being able to actually see it from six or eight or 10 feet away where most people would just see nothing or just a bunch of rocks, it's a very interesting process that your mind goes through. So that's what I would say about that part of the question.

NNAMDIMatthew Carrano, the other part of Maureen's question?

CARRANOAbout the Precambrian of Ojai, I can't say that I know it specifically. You know, once you're, you know, sort of doing your graduate work, as our caller I'm sure knows, you tend to specialize relatively finely. So I work primarily on dinosaurs and on the period of time they lived in which is the Mesozoic Era, which is about 400 million years too late for what she's asking about.

CARRANOI can say, though, that Cal State, Northridge continues to have a strong paleontology presence and that I'm sure that the staff there are still tied into the local fossil, you know, scene which, you know, most of us are -- the local history is always important, I think, to whatever institution you're at and I think -- whether it's university or museums. So I'm sure they know and would be happy to talk about it.

NNAMDIMaureen, thank you very much for your call. You too can call us at 800-433-8850. Do you have kids going through a dinosaur phase, or do you go through a dinosaur phase a lot like Dave Hacker did after he was supposed to be putting his kids through the dinosaur phase? 800-433-8850. You can send us email to kojo@wamu.org. Alton, we were talking about a whale you dug up in Yorktown this year, but our listeners might also have read recently about another whale that's been emerging from cliffs along the Potomac in Stratford, Va. Why is this area, which is close to Robert E. Lee's birth place, so rich in fossil deposits?

DOOLEYWell, those deposits belong to a rock unit that's know as the Calvert Formation, and that it extends through Calvert County, Md., all along the shores of the Chesapeake Bay and up a lot of the rivers along the coast. And it's well-known for producing fossil whales. There are, for baleen whales, probably at least seven or eight species that are known from that unit, and many of them are known only from that unit.

NNAMDIAnd more -- and there -- and that's more than you can find just about any place else in the world, correct?

DOOLEYIt's right up there. There are few places that are comparable, but the Calvert Formation is one of the best studied units. Again, paleontologists have been working on that unit for nearly 200 years, and so we've learned quite a lot about it, although there are still all the things out there waiting to be discovered.

NNAMDIMatthew, why is our area so rich in fossils of ancient sea life? Why not dinosaurs?

CARRANOWell, you know, we have both actually, but because we're located near the coast, and we have been located near a coast for many tens of millions of years, as the ocean has risen and fallen, portions of our area have been inundated and therefore have been the recipient of sediment with animal remains in it. And that those periods come and go, and rock layers are put down and they -- and marine life, in particular, preserves often very well in these layers.

CARRANOAnd so we just happen to be kind of lucky geographically. Our issue with the dinosaurs is that a lot of the areas where we want to find those dinosaurs is vegetated or built up or in other ways inaccessible to us in terms of seeing the actual rock.

NNAMDIAlton, one of the world's richest deposits of ancient sea fossils is right outside Fredericksburg in Carmel Church, Va. You've been working at that site since you were an intern at -- it's my understanding, at the Virginia Natural History Museum. What have you been learning about why so many animals ended up there?

DOOLEYCarmel Church is a remarkable site. I've been working there over 20 years. We don't yet actually know why there are so many fossils in that one spot. The entire quarry that we're working in is only about 400 yards across, and we pulled tens of thousands of specimens out of that site over that time from over 50 different species of animals. Mostly marine animals but we get a few land animals, and there are also things that had washed out to sea.

DOOLEYAnd the big question that we're trying to answer, you know, when we first went to the site, we just wanted to know what was there. And now we've progressed to what we're trying to figure out not just what's there but why is it there, and it's really been a mystery to us. We've looked at other marine deposits from all over the world trying to find something that's comparable to Carmel Church in terms of the number of fossils and the way the fossils are preserved.

DOOLEYAnd so far we haven't really found anything else. So we're still excavating several times a year there, trying to collect more stuff and hoping that we will eventually have an answer to that question.

NNAMDIWell, here's a curiosity. You found a pile of camel teeth in the middle of a baleen whale's skull at this site. It's hard to imagine that camels once roamed these parts. How did these land animals end up in the same site as sea animals? Alton.

DOOLEYWell, this -- the Carmel Church where the camel was found was -- while it's a marine deposit, it was close to the shoreline 14 million years ago, probably within site of the shoreline. We think the water there was only about 60 feet deep. And occasionally, when land animals that live fairly close to the shore, close to where they died, their carcasses will wash out to sea and be preserved there.

DOOLEYThe camel was a strange one. We have known -- paleontologists have known for a long time that camels have lived in North America or actually, originally evolved North America and lived here for tens of millions of years. And camels only went extinct to North America a few thousand years ago. We had not previously found any camels in Virginia, but we kind of thought they would be here.

DOOLEYBut this particular one, we only found a few teeth from it, and somehow when it washed out the sea, those teeth ended up being dumped on the seafloor where there was already a dead baleen whale laying on the bottom. And so they ended up -- most of the teeth ended up sitting on the top of the head of this baleen whale. Again, we're not really sure exactly how other than, you know, just chance that it ended up, you know, laying on top of a dead whale.

NNAMDIWell, I can imagine that there are whole bunch of hypothesis about why this could be happening. Tell us a little bit about the hypothesis that you are eliminating.

DOOLEYOne of the first things we considered was that this might be a calving lagoon where baleen whales were regularly -- some species of baleen whales regularly congregating in order to have their calves. Some modern species of whales do that. But what we realized pretty quickly is that while we are finding a lot of whales, they didn't represent just one species. We have at least six different species of baleen whales there, and no one specie seems to dominate.

DOOLEYThere's also a -- an interesting mix of both mature adults, adolescents and young whales. We're finding them across all different age groups. So we have pretty much ruled out that idea. We also looked at the possibility that while there are a lot of skeletons there, they may not have all been there at the same time. In other words, that this layer at Carmel Church may have taken tens or hundreds of thousands of years to form and that we were just seeing the steady accumulation of skeletons over a very long period of time.

DOOLEYBut we're pretty sure that that's not the case either, at least not for a lot of these skeletons because of the details of the way they're preserved. Essentially, the skeletons are preserved with so many of the bones intact and still connected where they would have been in a living animal, that we can't easily use a gradual accumulation to explain the presence of all these whales. So we've largely ruled that out as well.

NNAMDIWell, good enough. Obviously, there's a lot of them...

DOOLEYI could go on.

NNAMDIThere's a lot of them out there. Matt Carrano, there's been a lot of press lately about commercial fossil collectors who've been making big discoveries out West, selling their finds to the highest bidder. The Smithsonian was asked a bit for a pair of dueling dinosaurs that were discovered in Montana but decided not to. Besides the price tag, what kind of challenges do fossils found by commercial hunters present to museums as you look to expand your collections?

CARRANOWell, I think the primary challenge is whether enough original information and original data has been retained with the fossil to make it of any scientific value. You know, the difference for a museum is that we're not just trophy hunting. We don't just want the biggest X, you know, in our dinosaur collection. We want something that also allows us to learn about ancient life.

CARRANOAnd if someone's just collected a fossil, dug it out of the ground, won't tell us where it's from, didn't take any data on the sediments, the position of it in the ground or anything like that, we've lost a lot of information that's really important to us and which we can never reconstruct. Now, commercial collectors span the gamut. Some of them are professional level in terms of the kind of information they collect. Some of them are essentially going out and just smashing, grabbing fossils and running out of the ground.

CARRANOSo every time you see one of these, you have to kind of evaluate as a museum whether it's the kind of fossil you feel might be worth some attention or one where you really have to sort of say, no, thank you.

NNAMDIGot to take a short break. When we come back, we'll be continuing this conversation on local fossil finds and dinosaur news. But you can still call us, 800-433-8850. If you have already called, stay on the line. We'll try to get to your calls as quickly as possible. If you have questions for our Smithsonian paleontologists or our other guests, 800-433-8850. I'm Kojo Nnamdi.

NNAMDIWelcome back to our conversation on local fossil finds and dinosaur news. We're talking with Dave Hacker. He's an amateur paleontologist and fossil hunter. He's also a volunteer at the Dinosaur Park in Laurel, Md. Alton Dooley is curator of paleontology at the Virginia Museum of Natural History, and Matthew Carrano is curator of Dinosauria at the Smithsonian National Museum of Natural History.

NNAMDIYou can call us at 800-433-8850. We'll go to Christina in Arlington, Va. Christina, you're on the air. Go ahead, please. Hi, Christina. Are you there? Christina? Come in, Christina. I was relying on Christina to help me with my next question. I guess I'll have to go after it on my own. What are the options for museums when you know there's a significant fossil on private land you would like to have? Starting with you, Alton.

DOOLEYWell, we were talking earlier about the effects of commercial collectors, and that is one place where having these big ticket prices on fossils has an adverse effect. Sometimes when people find fossils on private land, what they look for is, you know, how much money they can get out of that fossil. And in most cases, museums don't have that many to give. A lot of dinosaur fossils, things like a Tyrannosaurus skeleton, sell at auction for more than my museum's entire annual budget.

DOOLEYSo that certainly has a kind of a killing effect on us being able to get assessments from private property. Generally, what we rely on is the generosity of the landowners to give us permission to excavate and hope that they recognize the scientific importance of the specimens and the value of putting that specimen into the public trust where it will be available to people for a long period of time.

NNAMDIMatthew, what are some of the scientific challenges that come into play when you consider studying or acquiring a fossil that was collected privately? I think you may have mentioned some of them already.

CARRANOYeah. I think, you know, the data that go with the fossil, really, always our primary concern. You know, once you have the object, you can always study the object. But unless you have some certainty about its origin and that it is what you think it is, a lot of the conclusions you draw are always gonna be suspect. So -- and I think our other concern, which is sort of a parallel concern, is there are museums and museum collections which are themselves private across the country that are not public museums.

CARRANOAnd a lot of those collections are essentially assets. So, you know, we're a museum to founder financially. Those things could be sold. Scientifically, when you study something, you know, one of the premises is that object that you studied is always available for future researchers. And so one of the jobs we do at the Smithsonian is we hold things in perpetuity. So I study things that were on interest 150 years ago, and I question hypothesis that were made 150 years ago with those objects.

CARRANOIf I do something and come up with an idea with a fossil, in 200 years, someone else has to be able to look at the fossil. If they can't do that, then what I've said is really of very little use.

NNAMDIDave, you don't have a Ph.D. in paleontology, but you're out there digging in the same areas where the experts are. How do you keep these private-public issues in mind when you're digging?

HACKERSo we have a lot of material in Maryland and at the Dinosaur Park that is not probably what people have in their mind. They have skeletons and lots of associated bones, I think, in their mind when they think about dinosaurs. We have isolated bones and lots of small fragments usually. That's -- so thousands of isolated teeth, bones and fragments for any time -- one time or we might have two bones that go together.

HACKERSo we don't have this problem so much, all right? So a single claw or a single tooth is not worth $1 million, all right? It's not really worth a lot of money. So it's a lot easier for us to do the education piece and explain to people that it's important scientifically, it's important to get it into a scientific collection and when these questions of ownership or what's it worth come up. And it's very easy to get people on board, OK?

HACKERSo we might have people walk in and wonder what it's worth, or can I bring it home? And by the time they leave our four-hour program or even if they're there for half an hour, they'd much rather have their fossil go into the collection than to bring it home with them. So I'm not sure if I exactly answered your question, but...

NNAMDIYou did. How did you learn to dig these things up properly? Do you really need to hit the books before you start digging, before you start looking?

HACKERNo, but it really does help to have a picture in your mind of what some of the fossils look like. So what we do out at the Dinosaur Park is we show people fossils that came from there before they start looking for fossils so that they get a image, a search image, before they start looking. And I will correct one thing. We don't dig at the Dinosaur Park at all.

NNAMDIYou look.

HACKEROn the other sites wherein, you know, depending on the situation, maybe paleontologists do dig. But one thing people don't realize is there's a lot of looking, and digging occurs more when you know where things are. And so what we do is we've got a lot of exposed ground that was exposed during previous mining operations. It's a former iron mine. And so what we do is we wait for the rain to actually wash out new fossils and wash the fossils off. So they wash the clay off of the surface of the fossils.

HACKERAnd then what we're doing out there is we're looking on the ground for those fossils. And the public programs help us because we get hundreds of people out there looking on the ground. Lots of look it -- lots of people looking means will find more fossils. And then if there happens to be something larger, like a bigger bone that's just starting to be exposed at the surface, somebody we'll see that, right?

HACKERAnd we don't want them to dig it out, but then we can actually call in people who know how to dig it out properly so, you know, somebody from the Smithsonian or wherever to come out and put a proper field jacket or whatever on it and dig it out properly. That doesn't happen very often. We have a lot of small isolated bones like I was describing. But it just happened, you know, it happens to be the case because of the type of fossil site that it is. But anyway -- so we don't really have a big problem with people...

NNAMDIGot it.

HACKER...having a profit mode of -- out at the Dinosaur Park.

NNAMDIBack to the telephones, Debbie in Greenbelt, Md. Debbie, you're on the air. Go ahead, please.

DEBBIEHello. Yes. I was wondering if you were familiar with the recent finding in the past year or two of a footprint at NASA in Greenbelt and also of the discoveries and findings of an amateur paleontologist Ray Stanford, I believe, is his name.

NNAMDIWe are very familiar with Ray Stanford. He was on this broadcast in 2005. If you go into our archives, you can probably find that. And I'm pretty sure Matt Carrano is also very familiar with Ray.

CARRANOYeah. I know Ray quite well. And the footprint at NASA was a good size footprint of what's probably an armored dinosaur called a nodosaur. And the land that Goddard is on is of the same age. It's a similar rock layer to what's out at the Dinosaur Park. Not the exact same moment in time but within maybe half a million years. And Ray himself has, you know, by his own time and training, become our local expert on dinosaur footprints. People had essentially not found dinosaur footprints here for the past 100 years.

CARRANOAnd then Ray has managed to find hundreds of them. And so, in fact, he's been over to that side as well and helped to verify the identity of that footprint. And so, you know, obviously, Goddard's came to preserve it as best as they can, and we've been talking to them about that. And in the footprints, although, as I said, Ray found hundreds of them, they're still comparatively uncommon because we don't have the kind of exposures.

CARRANOYou know, if you go out West, you might find the dinosaur trackway that's 500 meters long, which you're not gonna find here. So Ray finds them kind of one at a time. So it's an even more impressive achievement.

NNAMDIDebbie, thank you very much for your call. I know, Dave, you, too, know Ray Stanford. Ray is a well-known amateur paleontologist. He's published scientific papers on his amateur finds. But ultimately, we cannot have a fossil conversation without talking about the recent flap over the megalodon. The Discovery Channel kicked off "Shark Week" earlier this month with a documentary that suggested that megalodon still swim in our ocean today. Should this show really be called a mockumentary as some Twitter users called it?

DOOLEYI have to say I didn't see the show myself in part because I dropped my cable service several years ago because I was kind of appalled at the quality of documentaries.

DOOLEYBut from the clips I've seen in the show and from everything I have heard about it from other paleontologists, it was -- pretty much there was not a whole lot in the show that could be considered in any way scientific or accurate. Certainly, megalodon are not alive now. They went extinct sometime between about 2 million and 4.5 million years ago. And that's very, very well-established.

NNAMDIMatthew...

DOOLEYMegalodon actually has as a pretty good fossil record on the Atlantic Coastal Plain, in Maryland, in Virginia, North Carolina. And they are quite common in the sediments right up to 4.5 million years ago, and then they disappear from any of the younger sediments that we have on the Atlantic Coast. And you see that pretty much that same pattern all over the world where megalodon was found.

NNAMDIMatthew, could you tell us what megalodons are?

CARRANOYes. So megalodon is the sort of the popular name of a gigantic shark species that lived in -- up and down the Atlantic Coast and in some other areas for a few million years up until, as Alton said, a couple millions year ago. And you can find, you know, individual teeth of this animal that are, you know, six, seven inches long. At the Smithsonian, we have a reconstruction of the jaws that you can take your picture in front of and an adult can stand there. And the open jaws are big enough to, you know, encompass a whole adult.

CARRANOAnd so, you know, they're great -- they're sort of like the T-rex of the shark world. If you know a giant fossil shark, you know about megalodon. But I think around here, it's great because, you know, you can actually find the fossil teeth, you know, from here to Florida. And so they're, you know, unlike a T-rex tooth, which are -- you're less likely to encounter even if you go to Montana. They're the kind of thing you might actually see as a -- just an amateur collector.

NNAMDIHere is Marla in Woodbridge, Va. Marla, your turn.

MARLAHi, Kojo. It's -- I'm a longtime listener, a first-time caller. I'm very excited to be able to talk to you guys about this subject.

NNAMDISo are we.

MARLAI'm actually originally from upstate New York, and my family owns land up there. And I know some of the oldest fossils in the world can be found up in that area. And I actually pan and I do go back and occasionally collect some, so I have my own small private collection of little shells and really cool stuff like that.

MARLABut the biggest reason I'm calling is because I'm a homeschool mom. And the group of homeschoolers I spend my time with, one of them has a daughter. Her name is Maya. And I'm absolutely convinced that this girl is -- when she grows up, she is going to be huge in the paleontology world. She's...

NNAMDIObsessed.

MARLAShe's not just obsessed. She -- well, yeah, she is obsessed, but she's very knowledgeable on it and could probably...

NNAMDIOK. But we're running out of time pretty quickly, Marla.

MARLAOK. OK. The reason I'm calling about her is because I would love to know more information about the Dinosaur Park up in Laurel.

NNAMDIWell, here's the man who can give it to you, Dave Hacker.

HACKEROK. So the Dinosaur Park in Laurel is owned by Maryland National Capital Park and Planning Commission, Prince George's County, otherwise known as PG Parks. And I think there's a link to the Dinosaur Park site on...

NNAMDIYou can find it on our website, kojoshow.org.

HACKERYup. And so you can find all the information there. It's open to the public twice a month, as I said, on first and third Saturday. And so we have a free public program that you can come out to. And it's appropriate for all ages. And you can help us look for fossils, dinosaur fossils and other fossils from that time.

NNAMDISounds like the kind of thing that Maya would really enjoy. Marla, thank you very much for your call. I'm afraid we're out of time. For more information, you can go to our website, kojoshow.org. Alton Dooley is curator of paleontology at the Virginia Museum of Natural History. Alton Dooley, thank you for joining us.

DOOLEYThanks. It's great to be here.

NNAMDIDave Hacker is an amateur paleontologist and fossil hunter. He's also a volunteer at the Dinosaur Park in Laurel, Md. Dave, thank you for joining us.

HACKERThank you.

NNAMDIAnd Matthew Carrano is curator of Dinosauria at the Smithsonian National Museum of Natural History. Matt, thank you for joining us.

CARRANOAlways good to be here.

NNAMDIAnd thank all for listening. I'm Kojo Nnamdi.