How Modern Genomics Crushed Bigfoot Pseudoscience

Bigfoot? Or just a guy in a suit?


Thousands of people around the world believe in the existence of a large primate that roams the mountain forests. It is known by many names, such as Bigfoot, Yeti and Sasquatch. Many of these enthusiasts even claim to have genuine biological samples from these creatures. Skeptics have so far remain unconvinced. No authentic photographs or video material has been produced (the one on the right is a man in a suit) and no bodies have been found. Meanwhile, cryptozoologists complain that scientist are not taking them seriously.

To remedy this problem, Sykes et. al. (2014) requested samples from all over the world, subject them to rigorous decontamination protocols, amplified the DNA and then sequence them in order to find out their identity. Guess what they found?

How was the analysis carried out?

The researchers contributed to a press release requesting samples from alleged “anomalous primates”. They got almost 60 samples from all over the world, from the United States to Sumatra. After excluding samples that were obviously not animal hairs, such as plant material and glass fiber, they selected 37 samples based on their geographical origin and historic notoriety. A thorough decontamination procedure was used to avoid mistaken attribution of a sample to human x mammal hybrids that previous Bigfoot enthusiasts had done. After that, they ran a lot of PCRs on the mitochondrial 12S gene and sequenced the resulting product. Finally, they compared the DNA sequences to publicly available sequences at NCBI.

What did they find?

Out of the 30 sequences from which DNA could be extracted, only one matched human. This means that their decontamination procedure was highly effective. Out of the remaining 29 samples, 27 matched living mammals, such as brown bear, racoon, porcupine and cow. The last two samples was particularly interesting as they matched an extinct Pleistocene polar bear, but not their closest living relatives. However, the researchers conclude that the sequences probably belong to a previously uncharacterized polar bear species or a polar bear / brown bear hybrid.

Note: the bear sequence is now known to have had issues with degradation and probably came from a polar bear or a brown bear and not some exotic hybrid (note added 20160201 23:12 GMT +1).

What does this all mean?

In other words, all sequences that yielded DNA (apart from the ones matching the extinct polar bear) could be matched to currently living mammalian species. While this does not conclusively disprove the existence of a Bigfoot-like creature, it effectively refutes several dozen samples that Bigfoot enthusiasts claim come from this mysterious creature. Interestingly, Harry Marshall and Icons Films (both big producers of Bigfoot related media) contributed to the funding of this study. Looks like the results were not quite what they expected. At any rate, the cryptozoologists can no longer claim that real scientists do not take them seriously, but they will probably find ways to rationalize away this counter-evidence.


Sykes, B., Mullis, R., Hagenmuller, C., Melton, T., & Sartori, M. (2014). Genetic analysis of hair samples attributed to yeti, bigfoot and other anomalous primates Proceedings of the Royal Society B: Biological Sciences, 281 (1789) DOI: 10.1098/rspb.2014.0161


Debunker of pseudoscience.

32 thoughts on “How Modern Genomics Crushed Bigfoot Pseudoscience

  • “Guess the results were not quick what they expected.”
    Should read:
    “I guess the results were not quite what they expected.”
    IMHO, there’s no reason to let this kind of petty error make it to publication – EVER. Your articles are completely riddled with them, and they make reading your blog a chore. Sometimes, I can’t even tell what you mean to say, which makes me sad 🙁 .

    I’m sorry for being so blunt, but you don’t seem to really care about this, and it seems to be the only real problem with your otherwise excellent blog. Please take a moment to proof read before you publish!

    • While I believe that people should be open to constructive criticism, this comment is neither constructive or helpful.

    • Nor*

      Case in point. If you type something on a mobile device, autocorrect is likely to change words you don’t often use to other words.

    • I do apologize. I mean it purely as a way to improve the blog, but I won’t belabor the point.

    • Understood. I didn’t mean to imply that you didn’t have any valid points about the writing.

    • I suspect that Mr. Karlsson is not a native English speaker, so you might be a little more forgiving. He’s probably doing the best he can. That said, it bothers me too, but he still does much good detective work. Why not volunteer to copyedit his articles?

    • I actually use more English than Swedish on an average day. People have volunteered to copyedit, but I have declined.

      So yeah, I deserve all the criticism I get. 😛

    • Excuse me.

      I am being absolutely forgiving, and I’m in no way demanding perfection. I’m perfectly aware that English isn’t his first language, and that is part of my point – that he should take more care before publishing because of that. The errors I point out are so obvious that I’m sure he’s capable of seeing them – if he were only to look a bit more carefully.

      I am completely certain that he’s doing his best, which is VERY good, and is much appreciated. I have volunteered to help, and also recommended that he ask others too – but it’s really not my place to impose on his internal operations, beyond commenting about what I see, so that’s what I’ve done. All this is entirely because I like Emil a lot, and care deeply about his success.

      However, he hasn’t seem terribly interested in these errors in the past, and they are still cropping up – a LOT – so I finally left my comment.

      I do find it strange how, to some, ANY form of criticism, no matter how constructive and polite, is automatically taken as an inappropriate insult and condemned. Some people – if not most – are so hypersensitive that it borders on trolling.

    • Now I feel bad. It looks like I’m pretty sensitive too. Apologies all around.

  • Emil Karlsson,

    I’m hardly surprised by this. As much as we might like to believe that Bigfoot and other creatures like them are real, there’s little evidence that they could be and the more we find out the less likely it appears that they are.

    Humans have ancestors that might have closely resembled what a bigfoot is suppose to look like, but they went extinct long ago and it looks like we’re their only living decedents. Wouldn’t it be interesting through if there was another extant Hominid species out there?

    It would also be a nightmare for creationists.

    • Anyone interesting thing is the taxonomy of Bigfoot. Are Yeti and Sasquatch different ecotypes of Bigfoot? Or is Bigfoot the genus and Yeti and Sasquatch are different species? Could they reproduce and produce fertile offspring? Do they have the same number of chromosomes, or different like humans and chimps?

    • Emil Karlsson,

      Even assuming they were real, off course we couldn’t answer any of those questions unless we we’re able to capture one, or at least study a group of them in the wild.

  • So all the samples that were test only to show that they were of another animal or inclusive. Yet I remember back in 2012 hair samples done by veterinarian Melba T Ketchum saying of unknown primate species exist. Yet even that work is being debated or question. This lead to the question as to what is going on? Either Bigfoot doesn’t exist or the proper DNA evidence as yet to be discovered. Only a live specimen will resolve the doubt to the creature existence but considering human nature I fear that such a discovery would led to its extinction.

    • No, all the samples were not biological matter (e. g. glass fiber), plant material, did not contain any DNA, came back as extant mammals or came back as closest to an extinct polar bear. None of the samples were of inconclusive genetic origin.

      Ketchum’s paper was published in a journal Ketchum founded just to get this paper out. It failed peer-review in the serious scientific journals it was sent to. It looks like the anomalous findings can be explained by contaminations from multiple human individuals. The paper does not show evidence of Bigfoot or hybridization events between species.

  • Let us begin with the quote from Bryan Sykes of Oxford University who led the testing in saying “The fact that none of these samples turned out to be (a Yeti) doesn’t mean the next one won’t” from the Daily http://www.dailymail.co.uk. The testing done reveals that all samples Oxford University and the Lausanne Museum of Zoology received were not of any unknown animal or primate. And I remember and article form the Dalles Chronicle stating 57 samples were sent but only 30 were found good enough to be tests with a few detailed as unsuitable. Leaving the question as to what the other samples were as I have yet to find any other sources mentioning that information. But knowing the results of any DNA evidence will always be argued the only way to put an end to this debate is with a living specimen.

    • Sure, there is always the possibility of finding a new primate sample that will actually not match any known organisms. So although science can never mathematically disprove Bigfoot, enough evidence has accumulated to say that the entire edifice of Bigfoot enthusiasm that is built on these samples have crumbled.

      The scientific paper in question has more information about the nature of the different samples. It is open access, so you can read it for free. Most of the other samples were either not biological, not from animals or did not contain DNA. At any rate, you are grasping from straws.

  • Hmm I wonder if there is any possibility of a large primate to remain unknown in this day and age. Oh right the Bili ape.

    • I can’t quite tell if you’re being intentionally obtuse and sarcastic, or just short-winded. The tone of your comment is quite glib and suggests personal offense at not being believed – which demonstrates a non-scientific world-view (taking objective facts personally), a common feature of pseudoscience peddlers. Since you appear to be a believer, I’ll assume you are until you clarify. If not, then please ignore this.

      “Hmm I wonder if there is any possibility of a large primate to remain unknown in this day and age.”
      ANY possibility, sure. But that doesn’t make it likely by any means – which it isn’t. Nor does it mean it’s happened – which it hasn’t, in “this day and age” of molecular taxonomy.

      “Oh right the Bili ape.”
      No, not right; DNA shows it’s just a chimp – so… NOT “unknown” at all. If you’re going to attempt to claim science, then you must accept it always and absolutely, even when it disagrees with your preconceived beliefs.

      The true believers’ need to invent mystery and monsters where there aren’t any is just bizarre.

      BTW, the culture of the Bili ape is a potentially interesting area of study, in that they MAY act differently than other chimps, but that in no way supports any crypto-critter theory or any other unscientific woo.

    • That was just another chimp and the location was a large forest in Congo (torn by civil wars). Pretty different from the U. S. situation. Also, there is considerably more scientific evidence for that species than for Bigfoot.

  • I think my comments are not making it through, or being delayed a long time (like, hours).
    How long does it normally take for comments to show?
    Are you using an automated filter?

    • Right now, my Akismet spam filter is completely messed up. It has been that ever since I got a surge of race realists / proponents of anti-psychiatry several months back. It spams pretty much all legitimate comments, no matter if the poster has a previously approved comment or not. It is really infuriating.

      I have fished your comment out of the spam queue, and to answer your question, I try to check it once a day (get about 100-150 real spam comments per day).

      Several people have remarked on this issue and I am at a loss what to do. In the end, I think I am going to need to turn on registration required to comment sooner or later if the influx of spam comments (and thus the work required to fish out legitimate ones) becomes bigger. For now, I am going to try to turn some of the anti-spam measures off and see what happens. I’d much rather let 1-2 spam comments about spell casters curing HIV (without links) get posted than to having to fish up legitimate comments from the spam swamp.

    • Thanks very much for the extra effort. Akismet should “learn” whenever you de-spam something, but that appears to be a very common complaint.

      I believe it only happens when I’m replying to an existing comment, rather than commenting directly on the article. We’ll see if this one gets hit too.

      I’d hate to see the need to register. It might greatly decrease the participation, IMO.

    • Looks like turning off some of the anti-spam measures did not help. Legitimate comments are still marked as spam (even those that do not contain any links). Akismet should indeed “learn” after a while, but after 6 months or possible even longer, I am tired of waiting.

      I would like to avoid the need to register as long as possible. It will likely reduce participation quite a lot. My next action is to automatically close comment sections on old posts. The default suggestion is 14 days, but I think that is too short. Perhaps 2-3 months is more appropriate. To give a feel for the problem, right now it says that “Akismet has protected your site from 503,508 spam comments already”. In contrast, the total number of legitimate posted comments are around 1600 and total views are 307k.

    • I understand that Akismet is not free, which must be very frustrating – I know I’d be livid.

    • Akismet is free for all WordPress.com blogs, so thankfully I don’t have to pay. Going to test closing comments on posts older than 6 months and see if that reduces the amount of spam I get.

    • I bet I am going to get a ton of “why did you close the comment section in the middle of our discussion! You are trying to silence me!!!11”

      Oh well.

  • Emil Karlsson,

    Speaking of Bigfoot, and science, have you heard of the so called Russian Bigfoot? That one if it turned out to be real could be even more interesting.

    Researchers Claim Proof Of Russian Bigfoot

    From what I’ve heard some crytozoologists believe that the Russian Bigfoot or Almas may actually be living Neanderthals. One particular story comes to mind that is quite interesting

    A Skeleton Still Buried and a Skull Unearthed : The Story of Zana

    Zana The Nineteenth Century Wild Neanderthal Woman

    The story of ‘Zana’, wild woman, has been solved through DNA analysis

    • Re: “Speaking of Bigfoot, and science,…”
      So, where’s the “science”? All those links lead to stories about nonsensical woo from true believers, not objective evidence.

      No offense, but the only interesting part is the psychology behind false beliefs, and their relationship to the systematic, for-profit fraud that is the Bigfoot movement.

    • Skeptek

      Where did I say that it was likely that Russian Bigfoot was a real creature? I didn’t. Maybe you misunderstood me? The first three links, are just there to point out what some people actually believe about the supposed creature, while the last one is to a skeptical website that actually debunks the claim that Zana was not a modern human, and that her son Khwit was a hybrid of a modern human and some other creature. (including possibly a neanderthal or some unknown ape like creature.)

    • Criticaldragon1177,

      Then I apologize. I misunderstood your position. I’m so used to statements like “The story of ‘Zana’, wild woman, has been solved through DNA analysis” leading to the opposite of what it says, that I honestly didn’t read the last article completely.

      Personally, I still don’t find any of that particularly interesting or even constructive, because it’s all just run-of-the-mill woo with a sprinkle of told-ya-so. At this very late stage in the tired and utterly worn-out Bigfoot saga, the ONLY thing that might actually be interesting would be real evidence of a new, unclassified animal. By now, even more revelations of fraud from Bigfoot believers wouldn’t really be news – it’s like reporting that the sun has risen.

  • I always love how cryptozoologists always say that you can’t disprove their beliefs. I applaud what Skeptek said that the Bigfoot movement is a For Profit Fraud.
    I actually had a “credible” cryptozoologist tell me that the definition of a cryptid now includes animals that were already known to exist, but now believed to be extinct. Also a melanastic animal is a cryptid. That is utter nonsense and I told him that by his new definition, an albino should also be classified as a cryptid. He then argued that I don’t have a degree in Zoology. When I pointed out that he didn’t have one either, he ended all communication.

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