Hair Whorls, South Paws and Guide Dogs

You’ve read ‘Hair Whorls in Dogs‘, and located and identified your dog’s whorls. Hopefully it was fun for all involved, but the story of hair whorls doesn’t end as mere anatomical curiosity; there is more to the story.

As I wrote in the previous blog, I was originally looking into sensory and motor laterality in animals when I got sidetracked by hair whorls; I’m going to continue on that path since it will eventually lead me back to where I wanted to go.

Among horse people [those who are into horses not people who are horses] there has always been some folklore associated with hair whorls.  Depending on the tradition, they were linked to everything from speed, intelligence, flightiness, amicability, aggression, laterality even associated with financial futures.

In horses, one correlation that has been confirmed is the link between the direction of facial hair whorls and motor laterality.1 Irish researchers found that a clockwise facial whorl is associated with right laterarity (RL) and anticlockwise (AC) with left laterality (LL).

J. Murphy, S. Arkins / Behavioural Processes 79 (2008) 7–12

Laterality refers to a consistent motor or sensory bias for one side over the the other. In humans, there is a population level motor bias of 93% for right handedness*. Sensory laterality is also common with people having a dominant eye or ear and if you’ve ever closed one eye to get a better aim or cupped  your ear then you also understand sensory sidedness.

Australian researchers2 found a similar pattern with hair whorls and sidedness, but this time with chest instead of face whorls.  And again clockwise chest whorls are linked with RL and AC with LL. The same Australian team developed two novel tests for motor and sensory laterality, the first-stepping3 and the sensory jump test4.

Everyone knows that doing things on one side is easier than the other. If you play any racket sport, hitting the ball is easier if it’s on the racket side; if you are a left-footed striker,  you want the goal to be on your right side so it should come as no surprise that dogs also perform better on their strong side.  The same Australian group found that success in the guide dog training program was higher for non-left preferent dogs5 (ie. right preferent and ambidextrous), and I suspect it’s the same for high performing sport dogs.

Anyway, I had written a whole lot more when I found the video below which made a lot of what I had written redundant. I had to delete large sections of the original draft, I hope it retains some coherency.

The tests are shown in this video.

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I carried out both the Kong and Jump (with taped up Doggles) tests on my Belgians and they are both righties; though their endless clockwise circling gave it away at 8 weeks.

At the very least this post may give you something new to do with your dog.

*N.B.  One interesting finding that ran contrary to our overwhelming right handed bias was first reported by Jonas Salk (the developer of the polio vaccine) after observing predominant left side cradling in rhesus monkeys. It turns out that human mothers along with chimpanzees, gorillas and orang-outangs cradle their babies with their left arm. Salk later showed that babies exposed to the sound of heartbeats – where the ear would be if held on the left – cry less and gain more weigh that a control group. One final bit about brain lateralization; since the mother is using her left eye (and therefore right brain) to look at the infant, it’s been proposed that this makes her a more effective monitor of the infant’s emotional needs.

References

1. Murphy J, Arkins S (2008). Facial hair whorls (trichoglyphs) and the incidence of motor laterality in the horse. Behavioural Processes 79 (2008) 7–12

2 Tomkins LM, Williams K A, Thomson PC, Mcgreevy PD. Lateralization in the domestic dog (Canis familiaris): Relationships between structural, motor, and sensory laterality.  Journal of Veterinary Behavior: Clinical Applications and Research, v.7, no.2, 2012 March-April, p.70(10)

3. Tomkins LM, Thomson PC, Mcgreevy PD. First-stepping Test as a measure of motor laterality in dogs (Canis familiaris).  Journal of Veterinary Behavior: Clinical Applications and Research Volume 5, Issue 5 , Pages 247-255, September 2010.  http://www.journalvetbehavior.com/article/S1558-7878%2810%2900037-7/abstract

4. Tomkins LM, Williams K A, Thomson PC, Mcgreevy PD. Sensory Jump Test as a measure of sensory (visual) lateralization in dogs (Canis familiaris). Journal of Veterinary Behavior: Clinical Applications and Research Volume 5, Issue 5 , Pages 256-267, September 2010.  http://www.journalvetbehavior.com/article/S1558-7878%2810%2900019-5/abstract

5. Tomkins LM, Thomson PC, Mcgreevy PD. Association between lateralization measures and guide dog success. Vet J. 2012 Jun;192(3):359-67


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2 thoughts on “Hair Whorls, South Paws and Guide Dogs

  1. Very interesting reading (and watching). I haven’t discovered my dog’s preference because he is sound asleep right now and I don’t want to wake him up…
    About the cradling of babies with the left arm: I would think it is logical if the mother is right-handed. That way the mother has the preferred hand free for doing other things, even for caressing the baby. If I look at myself, that was the logical way to hold my baby.
    Thanks for the interesting article!

    • It would initially seem logical except that left handed mothers also predominantly hold their babies with their left. And in a French study it was found that only 65% of fathers cradled their child on the left.

      In one experiment, mothers were asked to hold a stuffed toy while another group was first asked to imagine the toy is a child in distress. The first group showed variation (left, right, centre) while the second group again held the toy on the left.

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