Page 10 - The 'X' Chronicles Newspaper - April/May 2022 Edition
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10 Why We Can’t Rule Out Bigfoot
Why We Can’t Rule Out
Bigfoot
by Carl Zimmer
In 2017, I got an email from an anthropologist
commenting on a new report in the Proceedings
of the Royal Society. The topic of that report
was Bigfoot—or rather, a genetic analysis of
hairs that people over the years have claimed
belong to a giant, hairy, unidentified primate.
The international collaboration of scientists, led
by University of Oxford geneticist Bryan Sykes,
found no evidence that the DNA from the hairs
belonged to a mysterious primate. Instead, for
the most part, it belonged to decidedly
unmysterious mammals such as porcupines,
raccoons, and cows.
My correspondent summed up his opinion
succinctly: “Well, duh.”
This new paper will not go down in history as
one of the great scientific studies of all time. It
doesn’t change the way we think about the
natural world, or about ourselves. But it does
illustrate the counterintuitive way that modern
science works.
People often think that the job of scientists is to
prove a hypothesis is true—the existence of
electrons, for example, or the ability of a drug to
cure cancer. But very often, scientists do the
reverse: They set out to disprove a hypothesis.
It took many decades for scientists to develop
this method, but one afternoon in the early
1920s looms large in its history. At an
agricultural research station in England, three such a claim. Instead of trying to prove that Fisher’s test couldn’t completely eliminate the
scientists took a break for tea. A statistician Bristol could tell the difference between the possibility that Bristol was guessing. It just
named Ronald Fisher poured a cup and offered cups of tea, he would try to reject the hypothesis meant that the chance she was guessing was low.
it to his colleague, Muriel Bristol. that her choices were random. “We may speak of He could have reduced the odds further by
this hypothesis as the ‘null hypothesis,’ ” Fisher having Bristol drink more tea, but he could
Bristol declined it. She much preferred the taste wrote. “The null hypothesis is never proved or never reduce the chances she was guessing to
of a cup into which the milk had been poured established, but is possibly disproved, in the zero.
first. course of experimentation. Every experiment
may be said to exist only in order to give the Bigfoot advocates have repeatedly
“Nonsense,” Fisher reportedly said. “Surely it facts a chance of disproving the null claimed that professional scientists are
makes no difference.” hypothesis.”
willfully ignoring compelling evidence.
But Bristol was adamant. She maintained that Fisher sketched out a way to reject the null
she could tell the difference. hypothesis—that Bristol’s choices were random. Since absolute proof was impossible, Fisher
preferred to be practical when he ran
He would prepare eight cups, putting milk first
The third scientist in the conversation, William into four of them, and milk second into the other experiments. At the lab where he and Bristol
Roach, suggested that they run an experiment. four. He would scramble the cups into a random worked, Fisher was charged with analyzing
(This may have actually been a moment of order and offer them to Bristol to sip, one at a decades of collected data to determine whether
scientific flirtation: Roach and Bristol married in time. She would then divide them into two that information could divine details, like the
1923.) But how to test Bristol’s claim? The groups—the cups that she believed had received best recipe for crop fertilizer.
simplest thing that Fisher and Roach could have milk first would go in one group, milk second in
done was pour a cup of tea out of her sight, hand the other. (Continued on Page 11)
it to her to sip, and then let her guess how it was
prepared. Bristol reportedly passed the test with flying
colors, correctly identifying all eight cups. A Different Perspective
If Bristol got the answer right, however, that Thanks to the design of Fisher’s experiment, the
would not necessarily be proof that she had an odds that she would divide eight cups into two Radio Show
eerie perception of tea. With a 50 percent chance groups correctly by chance were small. There with
of being right, she might easily answer correctly were 70 different possible ways to divide eight Kevin Randle
by chance alone. cups into two groups of four, which meant that
Bristol could identify the cups correctly by
Several years later, in his 1935 book The Design chance only once out of every 70 trials. To Listen To Past Episodes
of Experiments, Fisher described how to test CLICK HERE!