Tortoises may be slow, but they’re no bores. Or so suggests a recent study in the journal Current Zoology, “No evidence of contagious yawning in the red-footed tortoise Geochelone carbonaria“, the proud recipient of this year’s 2011 Ig Nobel Prize in physiology. Each year, the organization Improbable Research recognizes just that – the curious things that make you go “hmmm” or, in their own words:
“The Ig Nobel Prizes honor achievements that first make people laugh, and then make them think. The prizes are intended to celebrate the unusual, honor the imaginative — and spur people’s interest in science, medicine, and technology.”
That’s certainly the case with Wilkinson et. al.’s study investigating whether red-footed tortoises swap yawns. Despite science’s greatest accomplishments, scientists are to this day still baffled as to why a single yawn can move through a room. Three hypotheses have been floated to explain this party-killing contagion: that it is the result of either (1) a fixed action pattern (an innate, instinctive behavior triggered by a signal), (2) non-conscious mimicry (a sub-conscious “When in Rome” response), or (3) empathy (understanding another’s feelings).
The red-footed tortoise is one of many vertebrate taxa known to yawn and that responds to social stimuli, but neither non-conscious mimicry nor empathy has been documented in this species. Thus, to suss the source of this snooze-inducing phenomenon, Wilkinson et. al. set up a series of scenarios involving Alexandra, a red-footed tortoise conditioned to yawn on cue for her cohorts under three different scenarios. At the risk of boring you with the details, when all was said and done the tortoises showed no significant signs of contagious yawning, suggesting instead a social dynamic at work in the yearn to yawn.
Another example of herpetology at its zenith…
REFERENCE: Wilkinson, Anna, Natalie Sebanz, Isabella Mandl, and Ludwig Huber. 2011. No Evidence Of Contagious Yawning in the Red-Footed Tortoise Geochelone carbonaria.” Current Zoology, vol. 57, no. 4. pp. 477-84.