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.
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