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


                      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!
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