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Transcript for
Bigfoot DNA

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Blake Smith: This is the first official MonsterTalk episode.

Ben Radford: So, this is the point in which we don’t cuss anymore, or when does that start? [Laughter]

Blake: I can fix that in post. [Laughter]

Dr. Karen Stollznow: That’s impossible. [Laughter]


Blake: Welcome to MonsterTalk. MonsterTalk’s an audio companion to the website; where we’re collecting science articles that deal with monsters. If a creature’s weird, alien, mythical or bizarre we’ll talk about it. This is our first episode and introductions are in order our much talk panel consists of Ben Radford & Dr. Karen Stollznow and myself. My name is Blake Smith and I’ve been investigating paranormal encrypted matters as a skeptic for about ten years but have been reading and watching documentaries about the topic for more than twenty years. I’m a writer, researcher and web developer; and you could find a link to my bio and some of my more regularly updated websites on the show’s web home: Ben?

Ben: Yes, I’m Ben Radford; Investigator, Writer and Managing Editor of Skeptical Inquirer science magazine. I’ve been interested in cryptozoology and all its various manifestations from Chupacabras to lake monsters to Bigfoot, you name it for over ten years now. My last book, which was co-authored by Joe Nickell was Lake Monster Mysteries. So I spent an inordinate amount of my time looking into lake monsters and cryptozoological things.

Karen: I’m Dr. Karen Stollznow, a linguist with a background in Anthropology and History. I’m an investigator of pseudoscientific and paranormal phenomena, from a skeptical and scientific perspective. I’ve spent over a decade researching and road testing a range of beliefs and practices; including hauntings, psychics, cults, alternative medicine and linguistic phenomena. I write about my findings for a range of publications and sites, such as the James Randi Educational Foundation Swift (JREF Swift Blog), for, my bad language website: Skepbitch blog ( and my Naked Skeptic web column for the Committee for Skeptical Inquiry. I live and work in the San Francisco Bay Area, but I’m originally from Australia; the home of the Yowie, the Bunyip and Drop bears.

Blake: Tonight the monster we’re going to be talking about will be Bigfoot, the hypothetical North American ape…

Karen: …and all the variants.

Blake: …and many variants, and our guest tonight is going to be Dr. Todd Disotell and we’ll give him an intro in just a little bit. So depending on your point of view Bigfoot’s been a part of American culture either since the twenties, with the Ape Canyon incident, or as I like to think of it, starting from the fifties 1958 with the Gerry Crew footprints, and then of course it came into the big popular consciousness after the Roger Patterson film in 1967 since then there’s been a variety of sightings, lots of foot prints, alleged hair, but no unique DNA evidence, or a body, or skeleton, or any evidence that would convince most skeptics and since our panel is composed of skeptics, that puts us in the position of continuing our vigilant skepticism.

Ben: Absolutely, I mean it’s important to realize that there’s no shortage of Bigfoot evidence. The problem is of course that it’s not good evidence. So you know the history of Bigfoot evidence is very closely parallel to the history of hoaxes, everything from; you’ve got carpet fibers being passed off as a Bigfoot hair, and transmission fluid being passed off as Bigfoot blood, and you know, take your pick. So, you know maybe one day we’ll actually get some good DNA evidence. I hope that’ll come up at some point.

Blake: Now that carpet fiber you’re talking about, didn’t that turn out to be buffalo hide?

Ben: Well actually there’s a couple of them. The one I was referring to turned out to be Dynel fiber, which is used in carpets and wigs. That was found, as I recall, by Mr. Freeman who is of course a known hoaxer. That’s actually an interesting case because in that case it was touted as Bigfoot hair for several years, where people thought it was, it was claimed to be unidentified and it actually took, as I recall, several years before a physicist by the name of E.B. Winn, who finally identified what it was. Some people had said it was human hair, some people said it was nonhuman, unidentified hair, some people said it was man-made and finally this chemist said he figured it out it was in fact Dynel fiber, which is made by Union Carbide. That to me is instructive, because again, here was Bigfoot evidence that was claimed to be hair, and it was unknown, it was mysterious, it was unidentified. And in the end it was completely identified, but that didn’t mean that for months and years it wasn’t “unidentified”.

Blake: …interesting.

Karen: …and that’s what people remember.

Blake: …sure.

Ben: …right.

Blake: Did anyone ever investigate whether it was possible that was from a bald Bigfoot that was wearing a rug?

Ben: …uh… I don’t recall if… uhm [Laughter]

Karen: …good point. Good argument. [Laughter]

Ben: Well, no but in the other case you’re talking about, there was a case in Manitoba, I think it was, a couple years back, where there was a Bigfoot sighting up in Canada that was allegedly hair that was found from that [Bigfoot] and it did in fact turn out to be bison. And there was some question as to whether it was naturally left there from bison that are in the area, but not really that close to there; or whether it was basically hoaxed and planted there from a piece of pelt or hide.

Blake: Wow. We’re gonna have to do, probably a whole episode on Freeman. He’s quite a character, or was, I should say.

Ben: Yeah, he’s now hoaxing Bigfoot tracks in heaven, I guess.

Karen: [Laughter]

Blake: That’s a real possibility. [Laughter]

Karen: [Laughter]

Blake: He’s a guest on the Carson show, no doubt.

[Voiceover: MonsterTalk!]

Blake: Everybody accepts Bigfoot as sort of a cultural phenomenon, I don’t know…

Karen: He’s part of folklore.

Blake: Yeah, he’s in a lot of folklore and from a modern perspective, even things like the beef jerky ads, he’s just a part of American culture.

Karen: That must be a southern thing.

Ben: Messing with Sasquatch.

Blake: Messing with the Squatch, yeah.

Ben: Yeah.

Blake: You don’t see this in California?

Karen: No. Even though we should, because Bigfoot is most predominant here.

Blake: Yeah, it’s a west coast thing. For the most part. There’s a chart on the Wikipedia article that has a distribution of reported Bigfoot sitings. By far California, Oregon and Washington get the most, and then British Columbia and Texas… and Florida.

Karen: Yeah, always in the forests and the Redwood parks.

Blake: Right. It’s the frightening woods, is what it is, I think.

Ben: I would attribute some of that, at least in part to the phenomena in which sitings tend to spawn other sitings. So for example when I was looking at the Lake Champlain creature and the distribution of sitings there, in Lake Champlain between New York and Vermont, it was really fascinating how there were virtually no sightings, there were very, very few sitings until Sandra Mansi’s famous photograph was published in 1981. The siting itself happened in 1977, after which there were very few sitings. But it was it wasn’t until ‘81 when everybody heard about it, that’s when the reported sitings just spiked and increased exponentially. So, what that tells me is that regardless of whether there is or isn’t a creature in the lake, people reporting these things spawns other people reporting them because it’s in the news, and it’s in people’s minds and it influences their expectations.

Karen: …copycat sitings.

Ben: Yes, exactly.

Blake: Well, you know, and even if they’re not intentional, certainly once you’re predisposed to see a monster, than any unknown thing can become a monster.

Ben: And often does.

Karen: …interpretation.

Blake: Right.

Karen: If you go to the Bigfoot Field Researchers Organization, their database there, they have sitings in each state.

Blake: That’s right. The BFRO, they have different classifications of sitings, there on their site. The best I believe, if I remember correctly, is the Class 1 siting, where you’re really a hundred percent sure you seeing a Bigfoot.

Ben & Karen: [Simultaneously] Ummhmm.

Karen: It’s still subjective, isn’t it. But looking…

Blake: …right.

Karen: …sorry.

Blake: Versus it picked me up and carried me, that would be… [Laughter]

Ben: …I was raped by Bigfoot, and I can prove it.

Karen: Yeah. [Laughter]

Blake: I have DNA evidence all over my pants.

Karen: In looking at the chart that they’ve got about 411 listings or sitings in California which is… whew. 465 in Washington, 211 in Oregon

Blake: That seems like a lot if you just look at the number, but considering the population and the number of years they’ve been collecting the data, and the classifications of what constitutes a siting, that’s not as prevalent as you might imagine.

Karen: They’re very poor examples, I had a look at some in the local area, and reputedly there was a siting in a place called Walnut Creek, which isn’t too far from here, it’s near Berkeley. And what was actually sited, it was more of an audio thing. And someone heard a scream in the distance and attributed that to Bigfoot, and that was listed as a siting. And they’re all pretty much along the same lines as that. Just sounds and noises, really.

Blake: Yeah, they do try to send follow-up investigators, but I’m just not sure how critical they are. The BFRO has one thing, they are a for profit organization. It’s run by a guy called Matt Moneymaker and…

Ben: I love that name.

Blake: I know.

Karen: Is that for real?

Blake: Yeah, I always want to ask that. I’d really like to talk to Matt if we can get an opportunity to do so, because I’d like to know A. does he really make money on that, and B. is that really his name, is his name Moneymaker?

Ben: His name actually is Moneymaker, and in fact they do make a tidy profit. The BFRO has been accused, rightly, I think, of basically having these weekend getaways where they promise people they’re going to go out and look for Bigfoot and they charge hundreds of dollars, maybe thousands of dollars depending on which one it is, to have a bunch of people go out and, “Hey, we’re gonna go find Bigfoot”. The BFRO is indeed a moneymaking organization.

Blake: My understanding is that you go and you’re not actually allowed to run out in the woods and track down what’s making the noises. And I’ve always been curious as to whether he had what you might call sweeteners or something, someone out in the woods helping to make it seem more like an authentic Bigfoot experience. Because what they don’t seem to be carrying are dart guns and rifles and things to actually bring back a body and if Bigfoot were a real animal what I would expect is for hunters to bag one. No matter how rare the creature is, if it’s still alive I think it’s a reasonable expectation that somebody could snag one.

Ben: Yeah I think it’s interesting when you sort of look at some of these cryptids, and these mysterious animals from the point of view that, if they are in fact these remnants of existing unknown populations, if you look at them within the context of ecology and environmentalism and basically the decreasing habitat that’s available for all wild animals, not just these cryptids, and so you’ve got a situation which habitat for any and all animals that are not domesticated are shrinking by the day and whether it’s wild boar, or eagles or what have you, and it seems curious to me that as each day, and week, and year go by, that the available space for these creatures to exist and roam, gets smaller and smaller, so you would expect that with every passing week, and month, and year would bring us closer to hard evidence or a body but that doesn’t seem to happen.

Karen: That’s a really good point.

[Voiceover: MonsterTalk!]

Blake: So, we’re recording our first episode of MonsterTalk tonight. This is Todd Disotell, and he is a professor of anthropology at New York University, and he has a bachelors from Cornell, a Masters and a Doctorate from Harvard and his area of expertise is genetics of primate evolution. Is that fairly accurate?

Dr. Todd Disotell: Yes, perfectly accurate.

Blake: Super. And the reason we’ve asked Todd to come on tonight is because he has been on multiple episodes of cryptozoological television shows, usually in the role of the DNA analysis person so we’d like to ask Todd a few questions about his experience on those shows and where he stands on the mysteries of the North American primate. So, Todd how did you get involved in cryptozoological television shows?

Todd: Well, I have a history of working on the evolutionary genetics of primates and I have some colleagues in the field other anthropologists who knew of my work, knew that we could extract DNA from hair. My lab group had helped identify new subspecies of chimpanzees and gorillas, so I think the very first sample actually Jeff Meldrum, a well-known anthropologist who has been searching for Bigfoot, got me some samples that we analyzed, those turned out to be negative, and I continued to go along with it. Although I always told them I was very skeptical for multiple reasons but, DNA is DNA. If I can extract DNA and sequence it, I can tell you what it is. Or at least what it’s not

Blake: How does that work?

Todd: Well, we basically depending on the source material which can be, just last week I worked on a DNA stain on some shards of glass, some blood on some glass, we extracted the DNA from that. We can extract it from saliva from tissue and blood of course. We can get DNA out of hair, even from feces, so when an animal passes feces some of that animal’s cells are shed along with it and we can extract DNA. In fact for our primatological work that’s probably our main source.

Blake: Really? How do you separate the animal’s DNA from the other bacteria?

Todd: Well, we have all of the DNA in the sample, but, using the procedure called PCR or polymerase chain reaction, we use chemical reagents that are sort of specific to the group that we’re interested in. So I can use what we call PCR primers that will only amplify primate DNA, and, say not bacterial DNA. If I’m casting my net wider, I could look for mammal DNA, again, versus bacterial DNA. So, it actually doesn’t matter if there’s other DNA in the sample. We can zoom in on the DNA of interest.

Ben: Todd, I have a question.

Todd: Yes?

Ben: Ben Radford here, you had mentioned earlier that the sample that Jeff Meldrum had given you, you said that in two cases that it came back negative. What does negative mean?

Todd: Well, let’s make that even double negative. Several of my samples turned out not to have any DNA in them at all. Either because they were just too degraded or one I suspect wasn’t actually even sort of biological material. It didn’t dissolve in the presence of things that should destroy proteins and other things. Other samples had been exposed to the elements probably too long so that any DNA that may have originally been present, basically was destroyed. Light, water, heat, humidity all of these things can damage DNA. So, that’s what I mean by negative. The other negatives, of course, are when we say, well this is a pig, you know some kind of Suid and wild boar hair. We have scientifically proven that bears do indeed defecate in the woods.

Blake: [Laughter]

Ben: [Laughter]

Todd: One of our feces samples turned out to be Ursid or bear.

Ben: It took a Harvard scientist to figure that out, right on.

Todd: Hundreds of dollars, many hours of work and a $250,000 instrument to demonstrate that.

Ben: Right on Todd.

Todd: Other samples, probably our most common result, like the one we just got yesterday is human and that either because it was a human who broke into the guys fridge on the back porch and not Bigfoot, or it could have been contaminated by the people who collected it, or anywhere, sort of in the so-called chain of evidence.

Blake: That’s a great lead-in to one of my big questions. If you found Bigfoot DNA, what would you expect it to look like?

Todd: Well, the other reason I do this is, that’s an intellectually interesting question that we literally debate in my lab, my postdoctoral researchers, my fellow professors and I and grad students, we debate this all the time. What would it indeed look like? And I have sampled things from Australia from the Himalayas, from all over North America, and you know the lead theories of course are that it’s clearly primates. There are many people who think that it is basically a remnant population of Gigantopithecus, a fossil species thought to be closely related to orangutans and that’s probably the most common Russ Ciochon has published a book on this. Other people sort of subscribe to this. So if that was the case, what we would expect would be that, when I test, I get a DNA sequence from a sample, that it falls amongst the living primates, falls closest to the orangutans, but is not an orangutan, so that it’s several, literally millions years, or at least several hundred thousand years separate from the orangutan based on known mutation rates and so on. Other people say well it’s a remnant Neanderthal, indeed is a Neanderthal population that has survived. So again we would expect the sequence to be closest to human, but not within the range of modern humans. And now we actually have Neanderthal DNA sequences so we could definitely say, this falls within the realm of variation of known Neanderthals which there is over a dozen different Neanderthals have already been sequenced and the complete neanderthal genome should actually be complete within the next year or so. So we can we can really nail it down if it’s a purported Neanderthal. If it’s an orangutan or a relative of the orangutans we would see that, or it is any other primate. The DNA database that we look at is quite full for mammals. So if it was any other thing, if it was a giant ground sloth, which temporarily go bipedal but went extinct, you know, ten thousand years ago or more, we would see DNA signature that was related to sloths, but not identical to any. So I think we would identify it. If I had a sequence that I could not explain I’m perfectly willing to go forth with that. Before I do, I have multiple colleagues who run labs similar to myself, who, for many good reasons don’t ever want to analyze samples like this, or deal with some of these people. And I can see why sometimes but I’ve got agreements with multiple (they will remain unnamed) labs, that if I get something interesting, I will send them a tube or a sample and say, sequence this then I won’t tell ‘em anything else. You know, if I got two other labs to come back with the sequence that was close to orangs, but not an orang, we have, you know, an important finding. And as I like to joke with people, one of the reasons I can do this, is I’m a tenured professor, I can’t get fired for dabbling in fun stuff.

Karen: I came across a good quote of yours from Scientific American. And you said I go along with this because I’m either doing good science, finding alternatives, or debunking, or I have the find of the century.

Todd: Exactly. And so I don’t have any qualms in working on this. I generally try to screen who I directly work with. My main problem I guess is I try to keep this to the scientific level and my problem with many of the DNA, or the Bigfoot proponents is, they’re out trying to prove something, and that’s not what science can do. You know if you have an agenda I want to prove this, you are inherently biased and right off the bat, red flags you know, are raised. All we can do is disprove things. I like to tell my students, we’re left with the junk. We disprove every other thing and we have to just sort of provisionally accept the last thing left. The hypothesis that we we can’t prove it, but we can’t disprove it we’re stuck with that until proven otherwise, but, if you’re out there, I’m going prove Bigfoot exists, you, in my mind have instantly lost true scientific credibility.

Blake: Well put.

Todd: You might be able to find scientists to work with but if you already have that agenda, it’s too easy to make mistakes, gloss over things, not look at the obvious. Yes, bears do leave things in the woods. Just because you find a large pile of feces, you know, the first hypothesis you generate shouldn’t be Bigfoot.

Ben: Right.

Todd: It’s, what other animal lives here and eats berries and does these things?

Ben: If you hear hoof prints, don’t think Unicorns.

Todd: Exactly.

Karen: And do you find that that’s the bias of most people that you work with? Or not necessarily?

Todd: The proponents, definitely. You know, they are literally out there to prove something and, inquiry is great, if you want to go out there and trudge around the woods to look for something, that’s great. Cause you’re actually doing something positive. Instead of just hypothesizing it and writing about it, if you actually go out there and look for it, hey you’re going to get some exercise, we all need that. You might see something neat. Hopefully you’ll record the data well, and you’re not gonna do any damage. I occasionally worry about so-called Bigfoot hunters. I have had the conversations where my screening method fails me. I actually have next to my office phone I have a map of the United States with area codes and so there are just certain places I just let the phone go to voice mail from. Most of the Pacific Northwest, wide swaths of the south, etc. So I always have to apologize to colleagues calling me from Northeast Colorado cause I just never answer their phone calls, but I will answer their e-mails. There are guys who claim they hunt ‘em, I had one guy who, he actually sent me leaves, bloody leaves, this was the blood trail of a large buck. He even referred to them as a buck, that he had shot. But for some reason even though he shot multiple ones over the years, they actually cart away the bodies. They’re like the Vietcong. He could never actually recover the bodies

Ben: Very sneaky.

Todd: Yeah. He even told me he’s had dozens of sightings and he would never shoot a baby or a child or a female. He would only shoot a male and so I neglected to ask him what’s the size of their genitalia. How do you know it’s male, cause that would be interesting to know.

Ben: …and it might be scary depending on what answer he gave you.

Todd: Exactly.

Todd: Let me ask you, because you’ve brought up a very good question, which is something that I’ve pointed out, which is if people want to go look for Bigfoot, hey, knock yourself out, get a pair of shoes and a camera. What do you think about the argument, that the reason we don’t have good evidence for these cryptids, whether its Bigfoot or Chupacabras, or Mothman , or what have you, is that scientists, A. don’t take it seriously and B. there is no money, and that if just enough money were thrown at it, then the evidence would be there?

Todd: The money question’s a little tougher. Should the NSF National Science Foundation fund an expedition to look for this? Well, if they could marshal enough evidence to suggest there’s credible, you know, that they might find it.. if I was on that panel I would let it go. You know Jane Goodall and George Schaller wrote nice letters in their support. For e to get an NSF grant, there has to be a decent probability of a good outcome.

Ben: So, in other words, the money follows the evidence, not backwards.

Todd: Exactly. And there was actually just a big article on the New York Times this past weekend complaining about cancer research. We spend billions of dollars in a decade on cancer research without any huge, huge breakthroughs because everybody does the safe little incremental thing and unfortunately that’s sort of how it works. Can you imagine what some Congressmen would do to NSF if $200,000 or a quarter million dollars of the taxpayers money went to people running around in Washington State looking for Bigfoot? I wouldn’t wanna be on that NSF panel, but if they could demonstrate that there is some credibility to this, it’s the find of the century. North America, between the number of we have, and I grew up, I’m now in new york, but I grew up in the Midwest, I hunted deer, rabbit, pheasant, squirrel. I hunted anything that moved, for years growing up. There’s hunters all over this country. I have found bear skeletons and coyote skeletons, all sorts of wild animal skeletons out in the woods. Why hasn’t a single sample, single Bigfoot skeleton been brought in? You how much that would be worth? That’s a multi-hundred thousand dollar, million dollar find. We haven’t seen one. But the bigger problem with it and I do something also called conservation genetics. We look at highly endangered species and subspecies of primates all over the world. We characterize these populations genetics, how variable are they? You know, there are some populations that have so little genetic variability that, basically, unfortunately, they’re doomed.

Blake: That’s actually one of the questions I had for you, which is: what size a population do you need to have for a viable genetic group to live?

Todd: You need hundreds and I, frankly, cannot envision a population in the many hundreds of a large bodied mammal being completely hidden in North America. I mean, that’s my biggest problem. You can’t just have, you know, three of these guys hanging out hiding somewhere. You have to have a viable breeding population of hundreds of these individuals, and they can’t be spread out one per state. You don’t meet if that happens. So, that’s my biggest problem and that’s where I think they would fail if they actually ever submitted an NSF grant.

Blake: And I think that’s actually the Bigfoot paradox, is there’s the argument that they’re extremely rare and they live in very rural places, or hard to get to places, at the same time there’s hundred of sitings and lots of footprints around where people are, you can’t have both.

Todd: Well, exactly that is a paradox one clear as day photo. Why are all the photos blurry?

Ben: And furthermore, why hasn’t the photographic evidence improved since 1967? That’s what I find odd.

Todd: Yeah, I mean, every bozo in the world, even someone like me has a camera on their cell phone now. Samples, I’ve personally probably tested thirty samples in the last fifteen years. Not one of ‘em wasn’t something else. And, you know, it’s frustrating and sometimes I now question it, well I need more information show me a picture of where you collected it. What did you do when you collected it? How did you preserve it? Because, if I just said, “oh, I’ll test your sample” I’d get a thousand a week.

Blake: Ummhmm.

Todd: So I really need to see sort of the credibility, but the the other argument, they say well, we never get funding. To my knowledge, although I might be wrong here, but I have never been sent a grant proposal, nor a publication to review, via the peer review process, to do this. So it’s easy to complain about, oh we can’t get funding when’s the last time you submitted a grant.

Ben: Good point.

Todd: And I review a probably 50 grants a year, and maybe a hundred articles a year as associate editor to various journals or just ad hoc editor to journals being on National Science Foundation and other panels or just ad hoc reviewer. You can’t complain that they won’t publish our research or they won’t fund our grants, if they’re not submitted. And so I don’t know has Jeff submitted NSF grants to actually study Bigfoot? I’ll ask him next year at our meeting, I meet him every year at our meeting so I don’t know if he’s actually submitted an actual grant. I have never seen one.

Ben: I think your right. That’s one of the problems you’ve got, there is such a lack, and certainly you know this as well as anybody there’s such a lack of rigorous methodology applied to this. Just across the spectrum up to Bigfoot. So while I genuinely applaud Jeff Meldrum’s efforts to look at it, that’s great, we need scientists exactly like you, exactly like Jeff and others to look at this. I think that we would all agree that the issue of Bigfoot is a legitimate subject of scientific inquiry. But the problem is, is that, as you know, the quality of the research is so far below anything that would be published anywhere. I think that’s a big problem , and if Jeff and others want to get their act together and tighten up the controls and do solid research I think they would see it going somewhere.

Todd: If somebody put a grant proposal, and asked me to be on it, I would put my name down as saying they will send their samples to me, here is the protocol that I will use to test them, and here is how I will present the data. I will give my interpretation of the results, but the data won’t lie. So if a credible person wanted to say, we’re gonna go look, we’re gonna collect samples, if I can meet my costs, I’ll analyze those samples for them, in a grant proposal

Ben: That sounds great and it’s exactly the sort of thing they need to hear, so that the next time they say, oh well no one takes us seriously, it’s like, here’s one right here.

Todd: Oh, I’ve told them. Other people, in fact the group I just worked with, I’ll keep them nameless at the moment. They’re trying to create a new foundation they got some independent funding, etc. they’re looking for a lab to do their analysis and I’m not even trying to profit. I’m like I break even, I’m happy. as long as it doesn’t actually cost me money. But you know, when I put a post-doc, or somebody on it, it’s not like I can do this for $10 a pop. There’s real costs involved, but I’m willing to do those, at the breakeven point.

Blake: How much does an analysis, oh go ahead Karen, I’m sorry…

Karen: I was just going to ask, of these, you said you’ve tested 30 samples so far, what made those good enough examples for you to want to actually test them?

Todd: Well, some of them, probably, weren’t good enough, I’ll admit. Once you establish a relationship, say with the producer from a TV show… you know, the first sample he gives you, they have this great story, they have photographs and stuff, you’re like, I’m skeptical but I’ll do it for you. Once you sort of have a few pints with the guy after the shoot, and he calls you up a month later and says hey I’ve got another sample. You might be more willing to do it than you probably should if it was a cold call. But others, I looked at the samples, like well that sample looks like it’s in great shape. There’s fresh red blood there on that glass, and they quickly scooped it, up put in the freezer, I will be able to get DNA out of that, whatever it might be. Sometimes, when they’re like, “oh, we got this hand print on a window, eight feet off the ground, that’s been there for six months in the Florida sun”, you know, I’m gonna say there’s no way it’s gonna work. It’s just not worth the time and effort. I’m not gonna take people off real science projects to do a complete whim. But, if there’s a sample that looks like it could actually yield DNA, I’ll do it. Cause just, many samples, won’t. There’s not a chance in hell that they’re actually going have viable DNA and so I don’t even want to bother with those. And if the story is interesting I might go for it. Or, again, if I have a relationship with the group. I’m sure people who, I don’t want to keep harping on Jeff.

Ben: No, that’s okay.

Karen: [Laughter]

Todd: When Jeff asks me to do something I do it, cause we’re friends, and we have a relationship, but he’s not gonna… I’m sure Jeff even get guys who he thinks are crazy. He’s not going to pass them on to me. I count on my friends and colleagues and other people, to screen, if you will.

Ben: When DNA results come back inconclusive or unknown… what exactly does inconclusive or unknown mean?

Todd: If it’s a sample that literally just did not yield any DNA, I can say nothing. I can say I could not get DNA out of this sample.

Ben: So it doesn’t mean it’s a mysterious creature, it just means you couldn’t get anything out of it.

Todd: Right. If I’ve gotten DNA, I have never had a sample that I couldn’t say what it was. So, I’ve never had the, “wow, this is the DNA signature never before seen by humans”. I have never had that. The database is pretty full. The worst I could do is, I could say, it’s avian, it’s reptile, it’s mammal, you know, or it’s bacterial, but that’s assuming I have DNA. And that at least narrows it down.

Blake: This is kind of a nerdy question, but, if you don’t mind going deep for a minute? How does the actual database compare samples to known samples? Is it, like, does it do it at the ACGT level?

Todd: We literally compare the individual nucleotide bases and look for basically a percentage match. Modern human, all of us on the planet today, we’re about 99.9% identical. There’s only about a tenth of a percent difference amongst modern people today, on average. And so, if I get a 99.9% match, ah, it’s modern human and in fact, we’ve screened so many modern humans I can usually tell you roughly to which group it belongs. On the other hand, depending on the region of DNA, you know, we’re anywhere from 98%–99% identical to chimpanzees. Maybe about 97% to gorillas and 95%–96% to orangutans. So, it’s literally a direct match. And if it’s questionable or close we sample another region of DNA and get sort of independent confirmation of that. So if you have one little region that’s 99%, you’re like well, is that human or chimp, then you do another region if it’s also 99% then you realize we’re talking on the order of human-chimp differences. But, if the second sample’s even more similar, you say, well, the first sample was a little bit weird, two humans who were a little more different than you would expect, because these are averages, they have, these are mean values with standard deviations. The more data you collect, obviously the stronger your result. But when you’re differentiating Genera of mammals, is this on the orangutan lineage or on the human lineage, you don’t need a lot of DNA. If you’re saying, is this person European or Asian or African, you need a lot more you DNA.

Blake: Interesting. So how does it know where the sample, when it sees the string of nucleotides, how does it know where that falls, if you have a partial sample, or if you’re not able to get a good extraction?

Todd: The cool thing is it looks at it all. The computers now are so fast, I can get a 400 base segment of DNA, I literally can run it against the entire known published record, in milliseconds.

Blake: Wow…

Todd: I actually have the entire Human Genome, Chimpanzee Genome, Macaque Genome, Dog Genome, Rat, Mouse, partial Orang Genome and others on my laptop.

Blake: Wow…

Todd: Yeah, you can do this, you can actually, this is a publicly available database, you can either search for it using the government’s computers and it will take anywhere from 5 seconds to 15 minutes, depending on the time of day, and how busy it is, or you can download it to your own computer, and do it basically instantaneously. In my laboratory, we basically downloaded the database and then we updated every night, which there are tools that they give you to use. This thing it’s called GenBank the National Institute of Health (The NIH) pays for this large international database. It’s the ultimate freedom of information act source. It’s everything that’s published, everything the government’s paid for, is there almost instantly.

Blake: That’s so cool.

Todd: You can search everything in a matter of seconds to minutes, and again if I suspect it’s primate, to make it go faster, I’ll say only look at primates. But I could say look at all of life and in three minutes it will have searched every nucleotide, every ACGT ever known it will look for, and see if I get a match.

Blake: Wow, I love it. How do you go from, let’s say, if DNA is analog, how do you go to the digital mode? The machines do that for you, do they spit out the letters? I mean, how does that work?

Todd: Yeah. It’ll basically well in fact DNA is digital, if you really think about it. It’s, instead of being binary it’s got four bases. DNA is inherently, it is, A, C, G or T, at an individual spot. There is no intermediate, so and then, you just have to, if you have a hundred of those in a row, you match that string of a hundred of them, against all of the known DNA you get a result back saying 99 of ‘em match. You focus your energies then, on trying to figure out what that is, but, again, if it’s just 99 out of 100, like flipping a coin, now you want to do 1000 so is it literally 900 out of 1000, or is it 999 out of 1000? That’s what tells you the difference between say human and chimpanzee.

Blake: …so..

Todd: If you only flip a coin 10 times it’s unlikely you’re gonna get 5/5, right.

Blake: Yeah.

Todd: So, you do it 100 times you’re gonna have somewhere between 45 and 55, but it’s still not gonna be 50/50 even if you do it 1000 times, it’s not gonna be 500/500. But it might be 499/501, and you say good enough for me.

Blake: Sure. So it takes 3 or 4 minutes to run a sequence and compare it to the database. How long does it take to pull the DNA sequence out of the samples.

Todd: So, depending on how urgent, so let’s say you’re trying to solve a kidnapping case, and your checking the DNA of the guy who was stupid enough to lick the stamp, guess you don’t lick stamps anymore, but he licks the envelope that he mailed the ransom demand. If you wanted to know the result you could, the very fastest you could, I guess, theoretically generate sequence would be, maybe, 4–6 hours. We usually do a leisurely 2 or 3 days and that’s just because, if I said start extracting the sample, instantly start the analysis, and do it the second everything’s ready, cause if you do it the normal way you have a couple steps where there’s like 2 hour waits, you know, life cooking a cake in the oven cause it’s literally in an incubator. If you do it the really hyper-special way you can, it’s like using a convection microwave, instead of a 2 hour bake, you can make it 15 minutes. We normally don’t do that. Cause you know, if you did that, you’d never have any free time.

Blake: [Laughter]

Todd: If every fifteen minutes you have to do something, when are you gonna read your articles and write your papers? So, having 2 or 4 hours while it’s baking, you know you can go to lunch, you can read a paper, you can go have a pint, or whatever, then come back and get back to work. If you have to work every fifteen minutes, you’d be on an assembly line, and going insane. Normally, we do it, let’s say 2 to 3 days, and that’s leisurely.

Karen: Speaking of pints, I added you on Facebook last night, and I found your favorite quote is, “Everybody must believe in something, I believe I’ll have another beer”

Blake: [Laughter]

Todd: Yeah. I learned that from my advisor at Harvard. That was actually an engraved sign above his door and I’ve been practicing that ever since.

Karen: Then I knew you were a skeptic.

Todd: Science must be fun.

Blake: …and beer is good for what ails you.

Todd: Exactly. [Laughter]

Blake: That was my ale joke.

Ben: [Laughter & Groaning] Way to go, Blake, I thought we were just getting intellectual here.

Blake: Yeah, relatively pun-free. [Laughter]

Karen: It’s called a tone-down [Laughter]

Blake: So you mentioned that DNA is now available from hair samples, that’s a pretty recent occurrence, right.

Todd: Oh, let’s see, I think the first example of that, technically was 1998, so, depending on how old you are that’s either recent or a whole long time ago.

Blake: Oh, I remember, I meant from without, not requiring the root. That was the difference.

Todd: Yeah, if you have a root, you probably have a 95% probability of getting it, if you don’t have the root, it’s probably only 50/50 at the moment, and again, it depends how much time and money you’re willing to throw at it. If this is going to break the huge case, you know, and put a murderer behind bars, you’re gonna put more effort than if you’re looking at Bigfoot. So, I usually don’t throw the full toolbox at most of these samples.

Blake: But, if you came up with something interesting, you could then re-do the samples.

Todd: Yeah.

Blake: Right, gotcha.

Todd: Yeah.

Blake: Neat. So out of the DNA field, but still related to Bigfoot. What do you think of the morphological differences of the creatures of the creatures that are being reported across the country? Like 5 toes, or 4 toes; or 6 foot tall, or 9 foot tall.

Todd: You know the toe issue was strange, you know, sort of like the Simpsons. I would be shocked…

Blake: D’oh! [Laughter]

Todd: There is no other primate with 4 toes. There are a couple who’ve reduced their thumbs, but, you know, that’s a really evolutionary conservative feature, the number of toes. This goes, frogs and coelacanths have 5 digits. This is a general vertebrate trait. Unless you’re becoming a unicorn, well any horse, and reduce the number of toes, I can’t imagine a primate reducing it down to 4 toes. Height? Hey, I can look in my household, different, you know, anywhere from 5 foot to 6 foot. Seeing a 6 foot one vs. a 9 foot one, I have trouble with a 9 foot primate, personally they would be really big.

Blake: Well that’s, the gigantopithecus, you know, if it’s supposed to be somewhat like the orangutan. I’ve only seen them pictured, there’s kind of a famous model that shows one standing upright.

Todd: I actually just gave a lecture out at University of Iowa, where they actually have one of those original models there.

Blake: I just don’t, it seems a little odd…

Todd: It’s likely they weren’t that big, first of all. Because they have really big teeth and jaws, but I doubt if they were 9 feet tall. You know, I would be shocked if they broke 6 feet. Even a gorilla, you stand a gorilla upright, they’re not that tall. They’re much heavier than us, he can weigh 400 pounds, or a male orang can weigh 400 pounds, it’s not taller than you or I, though. So, you know, just because you have gigantic teeth in great big jaws, doesn’t necessarily make you 9 feet tall. It means, you have great big teeth, because you’re eating something that requires all those forces, and you have a big jaw to hold them, etc. So, I don’t imagine that they were huge, if a primate would evolve into Bigfoot, I don’t think they would be that giant, except for the fact that they have big feet, but I’ve yet to see a Bigfoot cast or whatever that hasn’t been proven to be fraudulent. If you call it Bigfoot when you make the footprints, you make ‘em big.

Blake: Yeah. [Laughter]

Ben: Well put.[Laughter]

Todd: If we call it Littlefoot, I guarantee you, there’d be a bunch of tiny little human-like footprints all over the place. I’ve actually helped analyze those. The Orang Pendek, from Sumatra…

Blake: …oh, yeah.

Todd: They call that one Littlefoot, and guess what they find? Little footprints!

Blake: There you go…

Ben: …suspicious [Laughter]

Blake: We’re gonna have to do another show on that too. [Laughter]

Karen: So, Tim, did you do some tests on the Orang Pendek, and find human DNA?

Todd: Yeah, but again, that’s what would fall under inconclusive. It was either they were being completely hoaxed, or, when they collected it, or the other people who analyzed it. If it was a contaminant it would mean the original sample is in such bad shape that there’s no original DNA left in it, and it only contains the contaminate. Because, the good news with the way we analyze our stuff is: if there really was Orang Pendek, or, let’s say Bigfoot DNA in a sample and the people who collected it, or my lab tech or somebody else contaminated it, we would actually get 2 signals, or 2 signatures. One would be, and you sort of, subtract off then; you sequence your tech, or you ask for hair from the guy who collected the sample.

Blake: …ahh, okay.

Todd: Subtract off their signature. So, let’s say you have a string of As, Cs, Gs, & Ts, that are really Bigfoot, and you have another string As, Cs, Gs, & Ts, that are that are the person who collected it. You could see at some points you’re have an A & a G, if the person who collected it is A there, you can reasonably assume that the sample is the G, something had to leave the G there. So, even if it’s contaminated, we can sort of subtract off the contamination. And even after we’ve done that, we’ve never had a DNA signature that wasn’t explained by being a human or some other mammal, or whatever.

Blake: Is that done all digitally as well, or…?

Todd: Yeah.

Blake: That is so cool. Do you have a scripting language you use with those programs, or is it built in, or…

Todd: It’s built in. I mean we’ve actually written a whole bunch of Perl scripts and Python scripts and other things, but in fact that’s just the standard tool set available with almost any DNA analysis package, commercial or open source that you might use. It’s all there. Even the government database gives you tools. They even give you the scripts, if you want to rewrite them and modify them for your own thing. This is one thing the government does really well. Is to make this data available to the scientific community, and the tools to analyze it. It’s, it’s… kudos to the government, on this.

Blake: Now, do you feed back into GenBank, as well, as you find…

Todd: …well, everything we sequence and publish, we give back. I don’t put my cryptos there, because, you know, they’re not crypto… They’re mountain goat, or bear, or pig, or human, so there’s no sense putting that in the database, because it’s already there.

Blake: Let’s hear a quick clip from Monster Quest, where they discuss a DNA sample that you analyzed.

[Begin Playback of Monster Quest audio]

MQ Voiceover: Mitochondrial DNA is the most accurate method known for species identification, and should be able to pinpoint whether the hair sample is that of a man, or a non-human primate.

Todd: Once we can recover DNA, we can amplify it, make billions of copies of it in a matter of hours in the laboratory and then we can sequence those copies. We can determine the exact linear sequence of the DNA bases, the As, Cs, Gs, & Ts. Once we have those, we can compare them to a database of basically all the known living organisms on the planet today.

MQ Voiceover: But, Professor Disotell has hit a wall extracting DNA.

Todd: We actually did not get DNA, so, in a sense, I don’t even have a result. There was not DNA present in the material given to us. Either, that material was so degraded that any viable DNA within it had basically been destroyed by other organisms or by nature; or, those were not biological samples.

MQ Voiceover: Dr. Curt Nelson also has been doing DNA tests on the blood, hair and tissue samples, and suspects there is an unknown substance, or inhibitor present, that is interfering with the DNA extraction. Nelson must first identify the inhibitor, and then remove it from the sequence. The inhibitor has been identified. The galvanizing on the screws was mixed in with the animal DNA. Nelson can now nudge DNA from the purified samples.

Dr. Curt Nelson: The scientific evidence at this point is suggesting that there really is an animal there. I cut it out, I re-purified it, and amplified it again using the same primers. I got a very strong reaction when I did that, and the reason was that I had gotten rid of the inhibitory stuff by running it out that way, and I found that it was identical to human DNA, except it had 1 nucleotide polymorphism. That nucleotide that was different, was a difference that is shared with chimpanzees. I got DNA that was primate DNA, and I knew that I might be looking at the DNA of a Sasquatch.

[End playback of Monster Quest audio]

Blake: Now, I, I… this is not gonna be a well constructed question, I apologize. The Canadian “screw board” DNA, my understanding was that after you didn’t find anything, they came back, and took it to a different place and had different filters and were able to track something down?

Todd: Uhhhhhh, how to be polite here?

Ben: [Laughter]

Karen: [Laughter]

Todd: Uhhmm, I actually eventually received those sequences. They were, I don’t remember if it was 1 or 2 bases different from human, but again you and I might differ. So, my interpretation of that result was, with very careful and selective editing, a 1 base difference in that region is still a human. Just might not be you, might be the guy down the street. So, I honestly think, that particular example, was just an example of laboratory contamination. And I can’t tell you how often that happens. Our methods are so sensitive, that, you know, one molecule that you sneezed out last week on the tip of your pippetter, might be the one that you end up analyzing. So the Canadian example of, I mean, we were very careful with it, I honestly don’t think that 1 base different sequence which falls completely in the realm of modern humans, and that was what was edited out. I analyzed that sequence as well, I found there are humans with an identical sequence to that. The human sequence that they tested it against, was 1 base different. There are other humans with exactly that same signature, and so my…

Ben: …and so as always, it just depends what you’re comparing it against.

Todd: Right, exactly. Again, what do we mean by The human? Is that Yao Ming, or, you know, Vernon Troyer?

Ben: [Laughter]

Blake: Wow, good choice, yeah interesting.

Todd: Is it the tallest guy you know, or the shortest guy you know? Who’s Human? They’re both human, we’re variable.

Blake: Wow, well, this has been really great. You guys have any more questions? Karen or Ben?

Ben: Well, not for me. I think this has been very informative and interesting and it’s nice to actually let an expert sit there and talk a bit, instead of just having it cut down to little soundbites. It’s been fascinating.

Karen: I think that was gonna be my question, to ask, or to say that you seem to be the token skeptic on Monster Quest, and that you’re only afforded sound bites. Is there anything that you’ve ever said, that was critical, or revealing that was edited out?

Todd: All the time, seriously, all the time.

Blake: [Laughter]

Karen: [Laughter] I should have predicted that.

Todd: I’ve learned a lot, cause there is not a sentence you’ve ever seen one of those shows, that didn’t go through 6 or 7 takes. I mean, my 2 & ½ minutes on the average show, usually goes from about 8:30 in the morning to about 6:30 at night of actual shooting. I mean, a lot of it’s trying to get an egghead geek like me trying to say it in English, so that people can understand it who aren’t expert in the field, you now, but, I know the game. These guys are also trying to make an interesting show, and I’m more than happy. Hey, I get to talk about evolution on television to the masses, which, you know, not a lot of… the E-word doesn’t get mentioned often enough on the news.

Blake: That’s great, that’s true. AMEN! [Laughter]

Ben: [Laughter]

Todd: And, so I… that’s one of the reasons I do it, but I know some of these guys, and I’ll say we’ve had to re-phrase answers, to where I can say, “Well, hey, I don’t really think this.” to, “Well, the data doesn’t show that, so maybe it’s still possible.” And, in fact, that’s technically true. You know, scientists, we’re real humans too, I don’t have irrefutable evidence to say “Bigfoot does not exist”. Cause there is no such possible evidence of that. That’s not science. That’s a positive answer. I cannot say, “Bigfoot does not exist”. I can say no evidence to date has revealed the existence of Bigfoot, therefore it’s possible, and that’s how they always want to end the show. Well this test didn’t prove it but it didn’t disprove it. But, you know, again, you can’t disprove something.

Blake: Right.

Ben: They always like to exploit the fallibility of science, and the fact that nothing in science is ever definitive. And so, as long as they can get someone to say, “Well, you know this isn’t definitive”, it’s like, well you make up your mind.

Todd: Exactly. You called it the fallibility of science. I would turn that around, that’s the strength of it. We’re not religion, we’re not belief. We’re not infallible. That’s why I’m a scientist.

Ben: Perfect.

Blake: And that’s why we support skepticism. Exactly, that’s the best way to look at these things. And you sort of invoked a little rule, I don’t know if anyone else has come up with it, it’s the: Your screen time on paranormal shows is inversely proportional to your skepticism. [Laughter]

Todd: Yes, oh absolutely shows where I was extraordinarily negative, it’s down to, I think my record is, like, 48 seconds.

Blake: Oh, wow, Ben, he beat you!

Ben: That’s pretty good man, that’s remarkable, you’re doing well.

Todd: The better ones are when, they sort of, you know, the camera’s rolling but they’re no longer asking you about your own area, they’re just asking you about other stuff and that gets on it.

Blake: [Laughter]

Ben: My last show I am talking about Archeology and Architecture and Astronomy. Cause they asked me the question while they…, you know, I just gave my opinion. It wasn’t a scientific opinion, it was what I thought. And that’s what actually made it. Not 1 of my DNA answers made it, only my Architecture and Astronomy questions.

Blake: Well, I have to say it’s been really refreshing. I really appreciate you taking the time to answer all our questions. This is great. We really want this to be an opportunity for people to get out the skeptical viewpoint, and to get out the real science. Because, I honestly, this stuff is amazing. I mean, you talked about just DNA analysis for a little bit here, and I can already see, we could easily talk another hour about the ethical implications of what human DNA means to crime and all these sort of things. I’m sure you already run into that, but just, the science is so much cooler than just is there a giant ape in North America.

Todd: Yeah, so guys, get a TV show.

Blake: [Laughter]

Ben: Working on it. [Laughter]

Karen: [Laughter]

Todd: I now know some people, let’s talk.

Blake: Okay, you let us know. [Laughter]

Ben: Alright. [Laughter]

Karen: [Laughter]

Blake: Thanks a lot. [Laughter]

Todd: Okay.

Karen: Thank you.

Todd: Okay, Take care.

Karen: Bye.

Todd: Okay, good night.

Ben: Night.

Blake: That was excellent.

Karen: He’s fascinating, wow.

Blake: Yeah, that was really cool. I had hoped that he was way more skeptical than he was coming across on television, and that was dead on, that was awesome.

Karen: He wasn’t coming across much on television. They weren’t giving him much airtime in comparison to everyone else.

Blake: Exactly, exactly. So, yeah, this is great.

Karen: Oh, yeah.

Blake: Thanks for listening to MonsterTalk. Today, you heard an interview with NYU Professor Todd Disotell conducted by MonsterTalker’s Ben Radford, Dr. Karen Stollznow and Blake Smith. Music today was provided by Peach Stealing Monkeys, through the Podsafe Music Network. Thanks to Mrs. Dr. Atlantis, especially if she’s actually listening.


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