We know now that the ability to roll one’s tongue isn’t genetic and was based on some questionable research. So, is this a bit of very well done research, where someone in the 1970s would think this, or evidence of just another modern example of mistaken “fact”?
“Drums Of Autumn (Outlander, Book 4)” by Diana Gabaldon –
“It might, he thought. If the ability to pass through the stones was genetic—something like the ability to roll one’s tongue into a cylinder or color-blindness—then why not?”
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