The null hypothesis they developed was this: The hairs purported to come from Bigfoot (or the Abominable Snowman or other regional varieties of the creature) belonged not to a previously unknown primate, but to known mammals. They extracted DNA fragments from 30 different hair samples and were able to isolate the same short stretch of DNA from each. They then compared that stretch to the corresponding stretch of DNA sequenced from many living mammals.
The results were clear: The scientists found precise matches for all 30 samples in previously known mammals.
Does this mean Sykes and his colleagues have proved that Bigfoot does not exist? No. It simply means that Sykes, unlike Fisher with his tea test, could not reject the null hypothesis. The question remains open, and—if Bigfoot doesn’t exist—always will.
That’s not to say Sykes’ study didn’t offer its own surprises. Two hair samples from the Himalayas matched a DNA sequence that was extracted from a 40,000-year-old fossil of a polar bear. Stranger still, their DNA was not a match to living polar bears.
In their report, Sykes and his colleagues offer a scenario for how such a result could have come about. It’s possible that ancient polar bears and brown bears interbred, and some living bears in the Himalayas still carry a bit of that ancient polar bear DNA.
Some skeptics have offered up an alternative explanation for Sykes’ finding. It’s possible that the polar bear-like DNA actually comes from a living mammal—perhaps a brown bear—that happened to pick up a few mutations that created a false resemblance to that ancient polar bear DNA.
What these skeptics have done, in effect, is create a null hypothesis. And there’s a straightforward way to set about disproving it. Scientists would need to find more DNA from these mysterious bears. If other regions of the DNA also matched ancient polar bears, then scientists could reject the null hypothesis.
And so science carries on, from one null hypothesis to another.
- More Here
The results were clear: The scientists found precise matches for all 30 samples in previously known mammals.
Does this mean Sykes and his colleagues have proved that Bigfoot does not exist? No. It simply means that Sykes, unlike Fisher with his tea test, could not reject the null hypothesis. The question remains open, and—if Bigfoot doesn’t exist—always will.
That’s not to say Sykes’ study didn’t offer its own surprises. Two hair samples from the Himalayas matched a DNA sequence that was extracted from a 40,000-year-old fossil of a polar bear. Stranger still, their DNA was not a match to living polar bears.
In their report, Sykes and his colleagues offer a scenario for how such a result could have come about. It’s possible that ancient polar bears and brown bears interbred, and some living bears in the Himalayas still carry a bit of that ancient polar bear DNA.
Some skeptics have offered up an alternative explanation for Sykes’ finding. It’s possible that the polar bear-like DNA actually comes from a living mammal—perhaps a brown bear—that happened to pick up a few mutations that created a false resemblance to that ancient polar bear DNA.
What these skeptics have done, in effect, is create a null hypothesis. And there’s a straightforward way to set about disproving it. Scientists would need to find more DNA from these mysterious bears. If other regions of the DNA also matched ancient polar bears, then scientists could reject the null hypothesis.
And so science carries on, from one null hypothesis to another.
- More Here
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