The Skeptics Society & Skeptic magazine


Transcript for
Fins & Fossil Footprints

Read episode notes

Ben Radford: … a lot of the mystery-mongering books like Loren’s [Coleman], and Karl Shuker’s, and others are more than happy to sort of leave out the inconvenient parts.

Blake Smith: Well, it’s the same thing that happens with the ghost cases, you know, someone may explain a ghost photo, or a haunting, and then the explanation is never reprinted the way that the original haunting story is reprinted again and again.

Dr. Karen Stollznow: I call that ‘Chinese Whispers,’ the way that stories are passed down to people and just seem to morph, and change, become embellished.

Ben: Mm-hmm.

Karen: That’s the scientific term.

Ben: Chinese Whispers.

Karen: Yeah

Ben: Little linguistic term.

Karen: Yeah.

Ben: Yeah! Yeah!


Blake: Welcome to MonsterTalk. I’m Blake Smith, and together with my co-hosts, Benjamin Radford and Dr. Karen Stollznow, we examine stories about monsters to see what science and skeptical inquiry can tell us about the veracity of such claims. This week we’re going to talk about two monster stories. The first is the case of the Zuiyo-Maru, in which a Japanese fishing boat hauled aboard an animal carcass that looks suspiciously like a dead plesiosaur. The second case is that of the Paluxy tracks. These tracks were once touted as evidence that giant humans walked alongside the dinosaurs. Our guest today is Glen Kuban, who investigated both of these cases, and he will tell us about his findings and how Young Earth Creationists wanted to use both of these cases to try to disprove the Theory of Evolution. I think you’ll find it an interesting tale and maybe learn something new. I know I did.

Blake: If I could read something to you, The Case of the Zuiyo-Maru. I’m reading from the Reader’s Digest Mysteries of the Unexplained. On April 25th, 1977, the Japanese fishing vessel, Zuiyo-Maru, hauled aboard a huge carcass that no one had been able to—actually it says no one has been able to identify—and this was in 1980, I believe, when this book came out. ‘82, this is the updated version. Fifth printing is actually 1985, so this is one of those cases where I believe by 1985 they knew what it was, but they didn’t go back and fix the Reader’s Digest, so . . .

Karen: Just looking at some of the citations it doesn’t seem like too much was really done after the ‘80s into it. It seems like they sort of, um, they had some big conference, I think between France and Japan, some oceanographic conference, and they basically declared that these were the remains of a basking shark. The bulk of people in science seem to have accepted already that it’s just a shark.

Blake: Right, exactly, but the monster books are still reporting it as being a sea monster as late as 1985. Or at least unknown.

Karen: Did you read that article I sent to you about the Death Worm?

Blake: Oh I sure did. I’m very excited about that Death Worm research.

Karen: Yeah. I don’t know if you saw that, Ben. This was from the Herald Sun, which is a newspaper in Victoria, and it advertised the Acid-spitting Death Worm hunt in Mongolia, in the Gobi Desert, to find the fabled acid-spitting and lightning-throwing Mongolian Death Worm. So a fellow from New Zealand seems to be causing a lot of trouble at the moment. That’s the topic of what we’re discussing today. But it’s called the olgoi-khorkhoi, the Intestine Worm, because it resembles a cow’s intestine and is about 1.5 meters long. So the worm apparently jumps out of the sand and kills people by spitting concentrated acid or shooting lightning from its rectum over long distances.

Ben: How cool is that?

Karen: [Laughing]

Blake: It’s the fact that it can attack in two different directions, I think, that makes it so formidable.

Ben: Yeah, I remember at the Reporting Times Convention a couple of years back, I think one of the cryptozoologists, I think it was John Downs gave a recounting of his expedition to Ulan Bator to go check out the Mongolian Death Worm.

Blake: That’s interesting. So it spits acid, and weirdly enough if you take acid you’re more likely to see it.

Ben: Right, and yeah, there you go, and it poops lightning.

Blake: It does, it does.

Karen: Apparently there have been four unsuccessful expeditions searching for it in the last [garbled] years, and this New Zealand team, they’re going to try to bring the worms to the surface with explosives.

Blake: [Laughing]

Ben: Are they going to get that through security?

Karen: [Laughing]

Blake: That’s dangerous. I think what they should use is Thumpers. So, one of the things that amused me about that article was that they were using the position, Why would they make something like this up? as a reason why it’s plausible because, I mean, come on.

Karen: Yeah, it’s if rumors could inflate the reputation of things like the Loch Ness Monster and Bigfoot, but sparsely populated Mongolia was not a place where rumors were going to propagate. So, no reason to lie, that’s what he said.

Blake: Right.

Ben: That’s an interesting theory, I hadn’t, that particular thread of illogic I haven’t really come across.

[Voiceover: MonsterTalk!]

Blake: Tonight we’re talking with Glen Kuban. Glen, you come from a paleontological background, is that accurate?

Glen Kuban: More of a biology background, actually. I have a B.A. in Biology, I’ve taught high school biology, but I do a lot of active paleo research on the side, that’s kind of my passion, especially footprints, trace fossils, dinosaur tracks, things like that. But yeah, I’m also interested in the Creation-Evolution controversy and cryptozoology, and I guess that may be what you want to talk about tonight.

Blake: Yeah, we’ve got a couple of things we want to talk to you about tonight. You’ve been involved with some research on a couple of big cases that have been around for a few years, one for a lot of years if you think about it. But the first one is the Zuiyo-Maru case, and the second thing we’d like to talk about is the Paluxy fossilized tracks, which some people have alleged are human tracks next to dinosaur tracks.

Glen: Right.

Blake: So, how did you get involved in researching the Zuiyo-Maru?

Glen: Well, I guess I’ve been interested in cryptozoologies since I was a kid, even before I got interested in paleontology and the Paluxy tracks. But actually both groups—cryptozoologists and Creationists, as you probably know—during the 1980s and early ‘90s wrote quite a few articles suggesting that this carcass that was netted in 1977 in Japan might be some type of sea monster or plesiosaur. So after I read these various articles I decided to look further into it myself. I wasn’t really satisfied with the level of treatment that many of them had done on it and so I started gathering all the information I could and then wrote an analysis of it which was published in 1997 in the Reports of the National Center for Science Education. It’s kind of a skeptic’s type journal.

Ben: Yeah, why don’t you give a sort of background on the case.

Glen: Basically this carcass, which was quite large and did sort of resemble a plesiosaur—it had a small head with a long neck, four large flipper-like limbs—and one of the crew members took a few photographs of it and they did some quick measurements of it before they threw it overboard because it was stinking and they were afraid it would spoil the fish catch. But before that happened, some tissue samples were taken of one of the fins and that really helped resolve the case, although for some reason many of the people writing about it did not look into the results of the tissue analysis very carefully. But basically there were several lines of evidence which I think strongly pointed to it being a basking shark. Anatomically, its proportions matched a large basking shark and it’s well known that when basking sharks decay they often form what could be called a pseudo-plesiosaur type shape where tissue around the throat and gills falls away and leave the appearance of a small head and long neck. So basically it does kind of resemble a sea monster. But again the proportions are right for a basking shark, and then when the tissue samples were looked at, they matched a basking shark both physically and chemically. In physical appearance, their properties in terms of elasticity and translucence, things like that, were identical to sharks and rays, and specifically a substance called elastoidin which is only found in shark fins, no reptiles or other fish, even. And then the chemical analysis of the tissues gave a real tight match to the profile, the protein profile of a basking shark, and that pretty much clinched it, even though, again, the word didn’t get out too well for a while. But again if you look at all the evidence combined it seems pretty clear it was a decayed basking shark. And there were many previous cases where basking shark carcasses had been caught or washed up on shore and were initially mistaken for sea monsters but when studied better were concluded to be basking sharks.

Karen: I read your article, “Sea Monster or Shark” that you wrote for the National Center for Science Education, and I noticed that there was a disparity between the earlier opinions of the Japanese scientists and those of the Americans and European scientists. So why do you think that was the case with their earlier…

Glen: Well, I think it was just some initial reactions which conflicted. They all pretty much agreed in the end to the most part. Initially it seemed like the American scientists were somewhat more cautious or skeptical about the case. They didn’t want to suggest that it was a plesiosaur or any kind of unknown animal, because many of them were familiar with previous cases of basking sharks or whales or other known creatures being mistaken for sea monsters. So even the Japanese, some of the Japanese sources or the more popular newspapers and so forth, the scientists, once they did their tissue sample analysis they all pretty much came around to concluding that it was almost certainly a decayed basking shark.

Ben: You were talking earlier about the links between Creationism and cryptozoology. I’ve read some stuff by, for example, there’s an guy named Chad Arment who’s written a couple of books on cryptozoology, and I’ve heard some people talking about how part of the reason that many scientists—or at least I should say, many of the proponents, some of whom are scientists such as Jeff Aldrom—are really fighting for belief in Bigfoot and other cryptids, is because evidence for cryptids and these sorts of long-lost creatures would bolster the arguments, for example, for Noah’s Ark and other Biblical things. What’s your take on that?

Glen: Well, the Creationists who seize on these potential living fossils—if you want to call them that—what they seem to be doing for the most part is trying to argue that the Earth must be young, or geology, conventional geology must not be accurate if we find these living fossils which I think involves a major misunderstanding of geology and Earth history. There is no conflict between Evolution or an old Earth and the findings of these cryptids because once an animal group—or any organism, it could be a plant, even—appears in the fossil record, there is no reason why it has to go extinct at any particular time. It may appear to have gone extinct based on the lack of fossils, but we know the fossil record’s incomplete, so it’s always possible that the group or some remnant of that group survived later than we thought, even into modern times. There are many groups which many people think of as modern, like lizards and snakes and turtles which were living alongside the dinosaurs, so if another reptile group such as plesiosaurs happen to have a modern representative it would not destroy conventional geology or the Theory of Evolution or anything like that. It would just be another interesting case where we thought a group had gone extinct and we come to find out that was not the case. Now in the case of Bigfoot, I think that’s especially interesting, most Creationists have stayed a little bit farther away from that than, say, these plesiosaur cases because if Bigfoot exists it would apparently be some type of sub-human hominid-type creature, and that does not fit very well with strict Creationist ideas that humans did not evolve, that nothing evolved, that everything, all basic life forms were created by fiat just several thousand years ago. So most Creationists are not big on Bigfoot, so to speak. Like many scientists I’m fairly skeptical based largely on lack of physical evidence and the fact that it seems that most of the evidence for it is either anecdotal or based on things like footprints which can be faked, you know, rather than some compelling physical evidence.

Ben: So you’re saying that the main influence that Creationism would have on it would be either arguing for a young Earth or sort of challenging evolution?

Glen: Yeah, in the case of things like alleged plesiosaur carcasses, they would argue that 1) it might somehow disrupt the conventional geologic time-table. They seem to think that if scientists conclude that plesiosaurs went extinct with the dinosaurs, for example, then that is somehow some critical tenet of evolution, when really it is not. Now the Paluxy tracks which we can get into are a more interesting case. That would be much better support for their position if there actually were human tracks alongside dinosaur tracks because the general pattern of the fossil record does indicate that large modern mammals, and especially humans, did not appear until long after the non-avian dinosaurs went extinct. So the finding of human tracks back in the Cretaceous rocks with dinosaurs would, in fact, be a major problem for conventional geology, much more of a problem than say finding a modern plesiosaur, which all that would mean is that some group of reptiles survived longer than we thought.

Blake: In the case of Creationists who have used plesiosaurs or other brachiosaurs or a similar animal in Africa—that seems to be a popular one as well, and of course there’s the pterodactyls…

Glen: Right, right. In all those cases, like I say, they really—many Creationists imply they would be huge problems for conventional geologists to explain, but really not. In fact, just like with the discovery of the coelacanth, the gingko, conventional scientists would celebrate those finds. They would say, “Oh great. Some creature we thought was extinct is still alive.” You know, they would not be a problem for them whatsoever. On the other hand, again, finding human tracks in Mesozoic rock, that would be a different story. That would be a big problem.

Blake: How have the Creationists been using it in their literature and in their program? It seems like you presented a few cases where they had.

Glen: Yeah, well to be completely honest, they—the Creationists and cryptozoologists, for that matter—have really not used either of these cases in recent years very strongly. Most cryptozoologists have backed off from the Japanese plesiosaur and have acknowledged that itís most likely a basking shark. And in the case of the Paluxy tracks almost all the major Creationists leaders and groups have admitted that they were wrong or likely wrong in a lot of their initial identifications and that there is no compelling evidence of human tracks in the Paluxy or in the ancient rocks, as far as that goes. There are only a few individuals still promoting the Paluxy man-tracks, as they call them, but they’re considered disreputable or unreliable even by most Creationists, so really that controversy has faded, most of them have back-pedaled from their older claims.

Karen: Have there been any major scientists or spokespeople who’ve rescinded their endorsement of this creature as being as a plesiosaur? Any one in particular?

Glen: Well it was primarily a few cryptozoologists and several Creationists who promoted the plesiosaur interpretation initially. I don’t think any of them were actually experts in the field of marine science or paleontology or anything like that. So, I don’t think it was ever the case where conventional scientists were embarrassed by misidentification. They—especially the American scientists—seemed to be pretty cautious initially and they speculated, you know, it could be a shark or perhaps a whale or a large turtle with the shell missing, something like that, but they waited for the tissue analysis before drawing any firm conclusions, which was good, you know. Unfortunately the initial sensational reports seemed to get a lot more attention than, you know, the scientific reports of the tissue analysis which pretty much…

Ben: Well, that’s always what happens, you know. The original claim is just this big headline-grabbing, you know, “Mermaid Found!” Oh wait, hold on, never mind. I was going ask, can you…

Glen: Well, that’s why basically I wanted to do the article, to kind of compile the history of the case, and explain all the lines of evidence which pointed to the fact that it was almost certainly a basking shark. To try to just set the record straight, that sort of thing. And occasionally you’ll still see an article here or there which is not familiar with the whole case and suggest that it could still be a plesiosaur, but those are few and far between. It seems like almost all Creationists, cryptozoologists and mainstream scientists have come to agree that it’s almost certainly a basking shark.

Ben: A lot of our listeners may not be familiar with the Paluxy case. Can you sort of give us a little thumbnail sketch of the whole incident and basically what your thoughts are on it?

Glen: Yeah, that’s something that’s largely consumed my spare time for about thirty years. I began investigating the tracks right after college in 1980, and would fly down to Texas and work in the riverbed for a week or two or three almost every year since then, and I was just there a few weeks ago in fact to try to finish up some mapping in the State Park where a lot of the tracks are exposed. It’s hard to summarize the case in just a minute or two. You can reference my website where I have many articles explaining the whole controversy.

Ben: What website is that, Glen?

Glen: Well, my homepage is and from that there are links to my Paluxy articles as well as my plesiosaur/shark article that will give listeners a chance to look into it in more detail, but I can try to summarize quickly. Around the turn of the century, in 1908, there was a large flood in the Paluxy, which is a riverbed about sixty miles south of Fort Worth, near the town of Glen Rose, Texas, and the flood ripped up some limestone layers revealing many dinosaur tracks, which the locals initially mistook for ancient elephant tracks. Some of the elongated forms, they thought were giant human tracks, or as they called them, moccasin prints, giant moccasin prints. And in the 1970s and ‘80s many strict Creationist groups seized on these tracks, they did a film there, took a lot of photographs, and didn’t do a lot of rigorous work but wrote a lot of articles, and again the film that promoted these elongated footprints as giant human tracks alongside dinosaur tracks and claimed that that proved that evolution could not be true and the conventional geologic time table had to be wrong and the Earth was only several thousand years old, which was kind of their argument, and this was one of their best tangible lines of evidence they claimed.

Before this, during my studies in college I began reading Creationist literature and ran across these claims about human tracks alongside dinosaur tracks, and I didn’t know what to make of them, and I wasn’t satisfied really with the level of documentation either in the Creationist literature or the mainstream responses. A lot of conventional scientists had dismissed the claims as just all carvings or all middle-toe impressions of dinosaurs or as one thing or another without apparently a lot of careful research to determine what exactly they were. So I decided right after college to fly down there and try to investigate and figure out what they were, and it turned out to be a perfect time. The riverbed was dried up and all the sites could be accessed and I was able to, with a friend of mine, clean off and photograph and study a lot of the impressions which were claimed to be human tracks. And it wasn’t before long we had concluded that some of them were just erosional features, natural irregularities, or erosional marks that had been selectively highlighted to look kind of human. And there were some cases of what appeared to be carved prints—most of the carvings were on loose blocks of rock. But there were some, definitely some striding trails of elongated prints which did not look like typical dinosaur footprints. Bipedal dinosaurs typically make footprints with three large toes, almost like large bird tracks, and these are much longer, and the toes are not very distinct on many of them, they did look somewhat like moccasin prints in some cases. But when we cleaned the surface very well we could see on almost all of them indications of a three-toed—a long three-toed pattern in the front. So it was becoming clear to us even before the end of our first trip that they must be some type of reptilian or unusual dinosaur prints, but we really didn’t understand what was causing them to be that elongated and take on that roughly human-like shape.

To make a long story short, in the subsequent trips there and further studies at other sites I found more and more examples of these elongated footprints and better and better indications of a three-toed pattern at the front. And it appeared to me that—at first I thought maybe there was a dinosaur with an unusually long foot making these impressions. And then it suddenly dawned on me, it wasn’t a dinosaur with an unusual foot; it was a dinosaur walking in an unusual fashion. It was putting weight on its soles and heels in what they call a plantigrade type way of walking. I call these metatarsal tracks because they’re impressing their metatarsals, their soles and heels rather than just being up on their toes like most dinosaurs. Well, when I showed this evidence to some paleontologists, initially they kind of downplayed it and said that dinosaurs, as far as we know, they don’t walk that way, so you must be mistaken, but I gathered more and more evidence and some very clear examples of these metatarsal tracks. And then in 1986 I gave a couple of papers at the First International Convention on Dinosaur Tracks and they all then agreed that these were in fact metatarsal dinosaur tracks and they did appear to explain most of the alleged human tracks in the Paluxy. And during all this I was also writing letters to many of the Creationists who made the claims urging them to come down to the Paluxy and look at the evidence that I was uncovering and reexamined, some of the tracks and trails that they said were human, because in almost every case you could see some pretty strong evidence of these dinosaurian toes at the front of their human tracks. I wasn’t sure if they had not cleaned the tracks well enough or that they just were selective in what tracks and which trails they had shown.

But in 1985, the evidence was becoming even plainer that many of these were dinosaur tracks because we noticed that, on their most famous sites, the digit impressions of the dinosaur’s tracks were infilled with a secondary sediment, and the infilling was rusting as we had cleaned and exposed them repeatedly. The iron in the infilling material was actually oxidizing and becoming a dark rusty brown color and was contrasting with the limestone and increasing the contrast. In other words, they were becoming more and more obviously dinosaurian. And finally after they saw enough of our pictures and diagrams and so forth, a representative from the largest Creationist group in California, ICR, the Institute for Creation Research, and representatives from the company that did the film, Footprints in Stone, they came down and were quite shaken when we showed them all the evidence, and they admitted that they apparently had made a mistake. And soon afterwards, they withdrew the film from circulation, and ICR stopped selling their book, although…

Ben: That’s—I don’t mean to interrupt—that right there is pretty remarkable. I’ve rarely heard Creationists admit they made a mistake.

Glen: Yeah, well, they weren’t too eager to do it.

Blake: That’s exactly… [Laughter]

Glen: There’s a little bit more to the story. John Morris, who’s now the Director of ICR—he was at that time the son of Henry Morris who was the Director—he wrote the longest Creationist treatment on the subject with the book called Tracking Those Incredible Dinosaurs, and when I showed him all this evidence, he looked quite upset and said, “I don’t know what we’re going to do, we just printed thousands more copies of this book.” And I said, “Well, John, you’re going to have to tell people the truth,” and he says, “Well, I don’t know what we’re going to do, I don’t know what we’re going to do, I have a lot of pressure from the group,” and he was saying things like this, and then he said, “Well how do I know that some of these features weren’t painted on the tracks?” And I said, “John, you can see that, you know, there’s not just the color contrast, but there’s indentations or cracks or other indications of these three-toed dinosaur patterns on the tracks, you know.” And he said, “Yeah, I can see that.” So he admitted on site, in other words, that these were actually dinosaur tracks, that the coloration features were part of the infilling phenomenon, they weren’t—it wasn’t painted on. And he also acknowledged that there were cases of carving in—highlighted erosion marks and so forth. But he says, “I don’t know if I can just come out and say all this.” He kept looking for ways to kind of backpedal without admitting fully that they had misidentified these things.

Blake: Did they consider putting a sticker on their book?

Glen: Well, yeah, he actually did keep selling the book for a while, and in most cases did not have disclaimers in it. Eventually he stopped selling it. But what really disturbed me is that he—when he did finally write a statement about the tracks he said—he admitted that they had made some possible mistakes, but that it is possible that some of these features may have been artificially applied with paint or acid or something like that. And in the context of talking about my research he kind of insinuated that I or my colleagues might have doctored the tracks to make them look more dinosaur-like when he admitted on site that that was not the case, so that disturbed me, that he could not just come clean and say he was wrong. In any case, most groups, they praised him for admitting the possible mistake, and ICR and other groups no longer promote the tracks. There are only a few individuals that still do so and again, they’re not considered reliable even among Creationists, so the controversy has died somewhat.

Blake: Well, I knew that John Green, Bigfoot journalist, had written about these tracks and wanted to know why no specialists in fossil footprints had investigated them, but he wrote that a few years before your investigation.

Glen: Yeah, I was—I didn’t claim to be a fossil footprint expert when I began studying the Paluxy tracks, but I’ve learned an awful lot in the course of my research and I have often worked with professional paleontologists in the Paluxy, and in fact just a few weeks ago again I was doing more work with some paleontologists, Jim Farlow from Indiana Purdue University, and representatives from the Texas Parks and Wildlife Department and so forth, so I’ve not done all this by myself, but I did kind of spearhead the resolution of the controversy, maybe because no one else was really doing it. For some reason, especially when I first started working, footprints in general, fossil footprints were not—didn’t seem to be too interesting to many paleontologists, and I think some of them might have been staying away from the Paluxy tracks just because of all the Creationists involved, made them more reluctant to get embroiled in the whole controversy, which I think was a mistake because we learned an awful lot about dinosaur behavior, locomotion, posture and so forth just from studying the dinosaur tracks, even aside from the human footprint controversy.

Blake: How big are these tracks, you said giant human footprints?

Glen: Well, they’re not all that huge. A typical metatarsal dinosaur track is about two feet long, sometimes shorter, but the portion of it which appears human-like is the metatarsal section at the back. These tracks appear roughly or superficially human when the digits are subdued by either erosion or infilling or mud collapse or some combination of those factors, and it’s that back part, the metatarsal segment, which roughly resembles a human foot. And in many cases it’s somewhat larger than a normal human foot; it might be, you know, fourteen, fifteen, you know sixteen inches long or longer, and that’s why when some of the locals during the Great Depression carved some giant human tracks in loose blocks, I think they were just trying to make better examples of what they assumed were human prints or human moccasin prints, and in the Paluxy, I don’t even know that they had any anti-evolutionary motivation. I think they were just trying to make a little extra money. They probably didn’t even understand that human tracks weren’t supposed to be with the dinosaur tracks geologically. And I’m not even one hundred percent sure that they sold the tracks as real tracks; they might have even admitted they were carvings, for all I know.

I recently, during my last trip, met the grandson of the man who apparently carved most of the loose slabs, and they recently found another one in the cellar, and the family acknowledges that this man did carve the tracks, his name is George Adams. They all have—the ones on loose blocks—anatomical problems, usually the toes are too long, the ball is misplaced, and so forth, and several have been cross-sectioned and sub-surface features abruptly truncate [garbled] depressions and that shows pretty clearly they were carved. But again, I think he was trying to make better examples of what he assumed were human tracks in the Paluxy riverbed, which again I think began when locals misidentified these metatarsal dinosaur tracks as human tracks, and when they’re not well cleaned they do look roughly like large human tracks. They do have that general shape. So it was an understandable misidentification for the locals. Now the Creationists, most of them I think were sincere but they could have done a lot better research, they just don’t seem to have—not cleaned and studied the tracks carefully and kind of jumped to the conclusion that they were human tracks, which was what they wanted to conclude they were. But again, most have backed off, backpedaled in recent years and very few promote them anymore.

Blake: Glen, can you tell us how footprints are fossilized?

Glen: It’s interesting. Even scientists debate the exact conditions under which different footprints are formed or fossilized. In most cases, though, it seems like for footprints to be preserved well, they need to be made in moist but fairly firm sediment. In the case of the Texas tracks, it would have been a firm, limey mud. And during early Cretaceous times the ancient Gulf of Mexico came inland much farther than it does today, and when the tide went out it would have left a vast mud flat and the dinosaurs were marching through that, for who knows what reason. And then probably they dried out for a short period of time, maybe days, maybe in some cases a little longer, which sort of gave them a chance to get a little harder, kind of baking in the sun, before they were buried with another sediment. And again, for tracks to be well preserved, they in most cases would be generally buried and probably—and usually with a contrasting sediment. In other words if the original material was a limey mud that they walked through, if the sediment that buried them was a little sandier or coarser, that would help the layers to separate later, and that’s what happened in the case of the Paluxy tracks. There’s kind of an alternating sequence of different types of sediment, and of course the Paluxy riverbed was not there initially. Many visitors to the state park, they’re puzzled by the fact that all these tracks are in the middle of the riverbed and they wonder how they could survive for millions of years with the river flowing over them. Well, of course it wasn’t flowing over them, the river wasn’t there, the river just removed the overlying rock layers that exposed the tracks again. And of course while they were buried they gradually turned to limestone and that does help them to resist erosion, but they do erode fairly quickly once they’re exposed, you know. It only takes years or decades before they start to get eroded or broken away and washed downstream. Just since I began studying the tracks in 1980, many dozens of tracks have washed away or eroded badly in the Paluxy. But then sometimes the river cuts into the banks more and exposes new ones, so there’s still many good tracks to be seen there.

But it’s interesting, whenever I’m working in the Paluxy, a lot of visitors will come by and ask questions about how the tracks were made and some of them—I don’t mean to make fun but are kind of humorous. One lady had a very puzzled look on her face and I asked her what was bothering her and she said, “Well, I knew dinosaurs were heavy, but I never imagined they could punch holes in solid rock.”

Blake: [Laughing]

Ben: [Laughing] Oh wow. You gotta love scientific literacy among the masses, huh?

Glen: [Laughing] Right, you don’t know whether to even begin explaining it at that point. But most people do understand that the tracks are made in soft mud initially but many times they are confused how they stay preserved so well or whether the river was there all along and so forth.

Karen: So, how long will these tracks survive with the river going over them?

Glen: It depends a lot. The ones that are in the middle of the riverbed which gets the greatest force of the water action and the scouring from the sediment and so forth, they don’t last but a few years until they get noticeably scoured, and some of them that were quite nice when I first visited in 1980 are completely obliterated or very badly scoured now. When the track surface is moist, and it was raining on and off, it looks like a dinosaur just walked by a few minutes ago, they’re that clear. I posted some photos from my recent trip on my website photo gallery and I’ll be putting more up soon. You can see the tracks in the Paluxy are some of the best dinosaur tracks in the world, and sauropod tracks, which are made by the four-footed Brontosaur-type dinosaurs are, unquestionably, the best in the world. They show the digits, the claw marks really plainly, whereas sauropods tracks in other sites—and there aren’t too many other sites that have sauropod tracks—they usually just look like big potholes. They don’t have the details, the crisp features that the Paluxy tracks have.

And the three-toed tracks, they occur in quite a few sites. Most of the ones in the Paluxy are made by theropods which are two-legged meat-eating dinosaurs. But even though they are fairly common, the ones in the Paluxy are some of the best in the world. They have really distinct features; you can see the claws and tabs on each of the feet in many cases. So they’re quite impressive.

Ben: I was going to ask, just to change gears a second, I was going to see—what do you make of the often-heard Bigfoot claim that, when you bring up the fact that there really is no fossil record for Bigfoot, they often say, “Well, you know, bear bones are rarely found out in the wilderness and we know that bears exist, and therefore—” I’ve never really understood ‘therefore what?’ because we know that bears exist…

Glen: Yeah, I’ve heard that. As a matter of fact, a good friend of mine is a pretty avid Bigfoot tracker. He goes looking for it and believes it probably exists. I’m much more of a skeptic and I was never too impressed by that argument. For one thing, I don’t think the analogy holds up too well when you consider bear bones or other bones of large vertebrates, whether they be cougars or deer or whatever, they may be rare but they are found. Dozens and dozens are found every year. And not only their bones but complete carcasses and the living animals, in all those cases.

Ben: Right.

Glen: Many, many examples every year. What would be different about Bigfoot that would make its physical remains so much more rare that they’re essentially non-existent, other than their large footprints? You just don’t find bones or carcasses, ever.

Ben: Right, well you would also expect to…

Glen: its one thing to say to say they’re rare, but if they were rare you’d still have dozens of examples. But to explain why you never find them definitely becomes much more problematic.

Ben: Right, and plus if the Bigfoot were really twelve feet tall or depending on which one you’re talking about, then presumably the bones would be scaled up so that they should be even, you know, even larger and presumably leave an even bigger record.

Glen: Right, right. I mean, you could even make the argument, well maybe they’re burying their dead or something, but then you’d have evidence of the graves and so forth or tool-using or something. It’s just hard to explain why you don’t find any evidence of, you know, their—where they sleep, or their physical remains. So other than the alleged footprints it’s pretty much just anecdotal sightings and most scientists can’t put a whole lot of stock in that.

Ben: Well, it’s my understanding that extra-terrestrials come and snatch dead Bigfoot and they take them somewhere else and therefore that’s why we can’t find them.

Glen: [Laughing] That’s possible, I guess, but…

Blake: I think that’s a joke, though, right Ben? They really…

Ben: You know what, I’m sure someone’s made that claim. I think in fact…

Glen: You know, actually, I think that was an episode of the Six Million Dollar Man.

Ben: There you go! I miss Lee Majors.

Glen: They had an alien Bigfoot.

Blake: They did, they had a bionic Bigfoot, but I was just thinking that aliens prefer cow rectum and I think that…

Glen: That might have been before your time.

Blake: No, no, I was right in there with the Six Million Dollar Man.

Glen: Anyhow, I mean—Like a lot of people I would love for Bigfoot or any other of these cryptids as they call them to exist, but you know most scientists, they just want compelling evidence before, you know, accepting it, and that’s all I ask for too, you know. I’m glad to entertain it, but before I say it’s probable or likely, I want to see better evidence for it. Because I know from the Paluxy tracks and other things that people often do misidentify things or jump to conclusions, you know, and if they see something big and furry from a distance, you know, whether it’s a bear or somebody in a costume, you know, or some footprint someone may have faked, I mean it’s easy to jump to a conclusion. But in order to prove it scientifically, you know, it takes more rigorous evidence, I think.

Blake: Well, you actually, there’s some real good overlap here between cryptozoology and this particular misidentification of footprints, and so I’m glad you’re answering some of our questions here. Can you derive roughly how much a dinosaur weighed from the depth of the tracks?

Glen: No, not at all. That’s a common question but actually the depth of a print has a lot more to do with the consistency of the sediment than how heavy the animal is. If you think about it, you yourself can make a very shallow track or no track at all if you’re walking on firm ground. If you’re walking on soft mud you might sink in a foot. So it’s very hard to gauge someone’s weight from the depth of a print without knowing exactly how, you know, the density, the consistency of the sediment. And even in the Paluxy you can see where the same—what appears to be the same type and roughly the same size dinosaur will make prints of vastly varying depth depending on where and when he walked. You know, in areas where that mud appears to have been firmer there are very shallow prints and other areas where it appears the mud was soft the same size print will sink in, you know, very deep, sometimes up to a foot into the mud, you know, so… But you can get an idea just based on what type of dinosaur it is by the structure of the foot. You can tell whether itís a therapod, to like a meat-eater, or an ornithopod to like a plant-eater, and in the case of Texas tracks, most of the therapod tracks were probably made by a dinosaur called Acrocanthosaurus and we have its bones and some fairly complete skeletons and so we can judge based on the size of the footprint how big the animal would have been, using some reasonable guesses on, you know, how much fleshed out, about how much it would have weighed and so forth. It’s based more on the size of the prints than the depth of the prints. And you can calculate the speed, too, but again itís based on some assumptions about analogs of modern animals based on the size of the foot and the hip height and so forth and the length of the step, how fast, roughly, they would have been moving. But there are some formulas you can use to get a reasonable estimate for how fast a dinosaur in any particular trail would have been moving, you know, based on its pace length and its foot length.

Blake: So if two dinosaurs—a therapod and a sauropod crossing, and they’re roughly in the same strata track-wise, how closely can you tell whether they were—are they within years of each other or minutes of each other? Can you tell?

Glen: Well, on most of these sites, there’s very little doubt that, even when you have sauropod tracks, therapod tracks together, even in some cases ornithopod tracks too, some are little deeper than others, but it appears they were made, probably within hours or days of each other, most of the trails in any one particular site, because even though they may have dried out and, you know, not been buried immediately they couldn’t have been sitting out there for years or they would have been marred by erosion and weather and so forth, so at most its weeks or months, probably in most cases less than that at any particular track that was exposed before it got buried, and in the case of some of the Paluxy tracks, they are so clear that it looks like they were probably dried out and buried, you know, pretty quickly before any series of, you know, say, tides or weathering can crop up. Probably the first tide buried them enough where they were protected, you know, and came in fairly gently and just kind of settled into them.

There’s something else I was just thinking. On some sites, there may have been some laminations of different types of sediment where, as soon as the dinosaur stepped, some sediment of a different type will slosh right into them immediately where there almost instantly preserved in that sense, but there’s some debate about that. In any case, it looks like on most sites that there was not that much time between when different dinosaurs walked through the area. But of course, tracks are found throughout the fossil record, from invertebrate tracks in the Paleozoic periods to just dozens and dozens of, actually thousands of tracks sites throughout the Mesozoic, which is really difficult for a strict Creationist to explain how all these thousands of tracks sites were formed during the midst of a global flood, a violent global flood. It just doesn’t add up. Anyway, if you think about the large nesting sites that have been found in some areas, we have hundreds of dinosaur nests which would require that dinosaurs get together, mate, you know, make nests, lay the eggs, hatch the eggs, and so forth—it could not have happened in the midst of a violent flood, so it really puts a kink in their argument about the Earth being only a few thousand years old and the Flood explaining most of the fossil record. The tracks really seem to be a big challenge to that idea.

Blake: Sure, and so your work has been a big challenge to that too, apparently, so…

Glen: Yeah, I have not really pushed that particular argument, that line of argument, but I think I’ve mentioned it and I think Creationists realize that they really haven’t come up with a good explanation for that. The best they can do is just say something like, “Well maybe there were some lulls in the floodwaters,” and yet by their own other descriptions it was a rapid and continuous deposition, very violent, worldwide, and so forth. And even if you could say, you know, there were some periods where the floodwaters were less violent, where were all these dinosaurs while the thousands of feet of sediment were being deposited underneath? Were they treading water for months? It doesn’t make sense. And when you consider, like I say, besides the dinosaur tracks throughout the Mesozoic, you know, thousands and thousands of track layers of amphibians and other reptiles and invertebrates, insects, and spiders, even, things like that, all throughout the fossil record, and so explain how they could all be made in the midst of a global flood just doesn’t make sense. You know, you could get into radiometric dating and all the problems with that, too, that conflict with their model. But I think the tracks are really especially interesting because they really are a record of the living animal, and you can learn a lot about their behavior, their posture, locomotion, that you can’t learn easily from their bones or dead remains. And they’re very common, too. A lot of people think dinosaur tracks are fairly rare but actually they’re much more common than dinosaur bones, and that makes sense when you think about it, because if a dinosaur only had one skeleton that’s the most it could have left—of course many skeletons aren’t even preserved—whereas it could leave millions of tracks during its life, and at least some of them probably could be preserved.

Blake: That’s true. Well, Glen, I really appreciate you taking the time to talk to us today, and for taking so much time to investigate these questions because somebody needed to, and you’ve done some really good case studies here. Obviously this one’s captured your imagination, so…

Glen: Thank you. Thank you very much. It’s been a lot of fun, and as soon as I saw the tracks in 1980 I was immediately hooked on them, I couldn’t believe that more people weren’t working on them and itís been a passion of mine ever since. Did you want to—I know we’ve been talking for quite a while—you had a couple of other questions about how long it takes a fossil to form and so forth, did you want to touch on those, or are we pretty much…

Blake: Well yeah if you want to talk about that, yeah. How long does it take a fossil to form? [Laughing]

Glen: [Laughing] Well, interesting question because there really is no set answer. Some Creationists have tried to cite examples of very rapid fossilization or some say a modern object will be encased in a rock nodule or something and then try to argue, “Well, see, it doesn’t take long for things to fossilize, so maybe the Earth is very young after all.” But that really is a fallacious argument because even though some things may fossilize quickly—if you even want to call that fossilization—in other cases it appears that it requires many hundreds of thousands if not millions of years for something to be fossilized. But by fossilized, generally what we mean is that the original tissue or material is being replaced by other minerals or sediments and it’s turning into a more stone-like state. But that’s not really required. Actually for something to be a fossil, it has more to do with age than its composition or hardness. As a rule of thumb, if an organic object is older than about ten thousand years old it’s considered a fossil no matter how well mineralized it is.

Blake: Really? Even if it’s not mineralized at all?

Glen: Right. You can have, for example, a shark tooth which might be, say, many thousands of years old or even a couple of millions of years old and still retain most of its original material and have very little mineral replacement, because it’s extremely hard and dense to begin with. Things just don’t tend to absorb into it very easily. But it’s still considered a fossil as long as it’s over about ten thousand years old, and the reason they use that rule of thumb is that’s the beginning of the Holocene would be about ten thousand years ago. The Holocene is considered the modern epoch, essentially. So anything that’s pre-modern, pre-historic, if you will, is considered a fossil if it’s the remains or trace of any living thing. And of course even a footprint can be considered a fossil, a pre-historic footprint could be considered a fossil, but if the sediment it was made in is not completely petrified or it might still be pliable and in some cases they are, that doesn’t mean it’s not a fossil. And the composition might be almost identical to what it was originally; itís just maybe gotten a little harder. But that has nothing to do with whether you consider it a fossil or not, so…

Anyhow, there are many types of fossilization and the rates at which something becomes hard or mineralized varies a lot depending on the conditions—what other minerals are in the surrounding sediment, how fast the water might be leaching through it, and so forth. So it varies a lot. There are some things which can become encrusted or somewhat mineralized within decades or centuries, and Creationists like to seize on those and say, “Well, see there? It can happen very quickly.” But just because it occasionally happens quickly doesn’t mean that it usually does, it doesn’t in most cases.

Blake: Well, that’s a bit confusing, though, Glen, because if anything that’s organic but ten thousand years or older is a fossil, but the world is only six thousand years old, then how could there be any fossils?

Ben: Something’s not jiving here.

Blake: [Laughing]

Glen: Well, that’s interesting, because in the Creationist framework, right, there would be, there should be no fossils and that, in fact, the existence of so many well-mineralized fossils does, in my view and of most scientists, strongly among mounds of other evidence discount their model, because there are things like, you know, Paleozoic invertebrates in wood and so forth that are thoroughly mineralized, they’re essentially completely turned to rock and, you know, they don’t, they can’t easily explain how that can happen in centuries or a few thousand years, even. They don’t have the mechanism or, you know, I mean, just because they occasionally find some Coke bottle in a limey rock notch, you know, rock slurries can harden around almost anything, but to completely mineralize something, absorb into all the tissues and become, you know, a stone-like object is something. You know I’m not an expert on lithology or something but it appears that all the evidence indicates it takes much more than a few thousand years. And again, if you look at the radiometric dating and all the other lines of evidence, you know, it just doesn’t add up that it’s all a few thousand years old. Besides, the order of the fossils is consistent around the world. Each period of geologic time has its own assemblage of plants and animals and is consistent like that in the same order around the world. They’ll find these alleged exceptions but, why are there only a handful of alleged exceptions? There should be millions and millions of out-of-order fossils if their model is true. There should be no trouble documenting countless examples, not just you know—The Paluxy tracks are just one of a few cases they could point at, they should have no trouble pointing to thousands if, you know, everything is going at the same time, you’ve got all them all fossilized together during Noah’s flood a few thousand years ago.

Blake: Yeah, exactly. I think there’s—evolution’s got a way to be falsified and no one’s managed to do it yet, but it would be really difficult to falsify Creationism if the whole premise is, God did it, so that’s the end.

Glen: Well, yeah, they can appeal to miracles but actually I think both can be falsified it’s just that they haven’t come up with any evidence that would falsify evolution, for example, the Paluxy tracks and in terms of Creationism I think they have a hard time explaining many things which I think do falsify their model, you know, whether it’s radiometric dating or the order of fossils, or I have some—on my Paluxy website near the bottom—I have some essays which I described as falsifications of Creationism, they’re very brief but I think they’re powerful arguments that show that the Earth can’t be only a few thousand years old. In just one example, the meteorite bombardment. If you look at the moon you can see that it was hit by millions of meteorites. Now the Earth being even a bigger body would have been hit by even more, and most of them, according to astronomers, would have hit within the first billion years of Earth’s history. But according to Creationists, the whole Earth is only maybe ten thousand years old at the most, so all those meteorites must have hit within that time frame. Well it’s completely incompatible with human survival, I mean even a few of those would have wiped out the human race but they’re millions. So, they can say, well maybe, like Henry Morris tried to say, well those are just scars of some battle between Satan and the angels or something ridiculous, or maybe the moon was created with those craters intact, you know, but if you look at it realistically, no, those are real craters by real meteorites, and they would have hit the Earth, too, and it’s just not compatible with a few thousand year history.

Blake: Well, you’ve given us a really good overview here of the dinosaur slash Creationism argument because—and this is going to come up again on MonsterTalk because we’re going to talk about dinosaurs in Africa and supposed pterosaurs that are still flying around, and so…

Glen: Yeah, well, those are [garbled] and if it’s possible you could reference my website, I have links to, again, the Z-M case and the Paluxy controversy, but as part of the Paluxy menu I have articles and essays on alleged living pterosaurs and the African case and so forth so, you know, in case readers want to…

Ben: Yeah that sounds good, in fact we might be able to put some excerpts or some links up from our MonsterTalk page, so…

Glen: Yeah, like I say, if you can even just do the because everything kinds of chains off from that…

Blake: Sure. Absolutely.

Glen: …they’ll be able to get whatever they want.

Blake: Well thank you so much for coming and talking to us tonight, Glen.

Glen: Okay, thanks very much for having me.

Ben: Good talking to you. Thanks.

Karen: Bye.

Glen: Take care. Bye bye.

Blake: Well thanks again for listening to another episode of MonsterTalk. Theme music provided by Peach Stealing Monkeys. Your hosts today have been Ben Radford, Karen Stollznow, and myself, Blake Smith. Our guest today was Glen Kuban and he was discussing the case of the Zuiyo-Maru sea monster, and the Paluxy dinosaur tracks. Glen’s website is Check it out, and be sure to check out, our website, and our sister site,, where we collect articles like the ones Glen wrote. Thanks.


Karen: They were barking sharks…

Ben: Basking whale.

Karen: I see no, [garbled]. I can’t even pronounce it.

Ben: Yeah!

The views expressed on this program are not necessarily the views of the Skeptics Society or Skeptic magazine.

Skeptic Magazine App on iPhone


Whether at home or on the go, the SKEPTIC App is the easiest way to read your favorite articles. Within the app, users can purchase the current issue and back issues. Download the app today and get a 30-day free trial subscription.

Download the Skeptic Magazine App for iOS, available on the App Store
Download the Skeptic Magazine App for Android, available on Google Play
Download the Skeptic Magazine App for iOS, available on the App Store
Download the Skeptic Magazine App for Android, available on Google Play
SKEPTIC • 3938 State St., Suite 101, Santa Barbara, CA, 93105-3114 • 1-805-576-9396 • Copyright © 1992–2024. All rights reserved • Privacy Policy