1
The Correlation Between Equine Facial Whorls and Lateral Behavior
Isabella K. Eyles
Equine Development & Behavior
Bridgewater College
11/28/2016
2
Summary:
1.
2.
3.
4.
5.
6.
7.
8.
Introduction
Methods & Materials
Data
Analysis
Limitations
Results
Acknowledgements
References
Introduction:
Hair whorls in horses, what are they, how are they important to us, and can
they be linked to accurately determine lateral dominance? Well to begin, “hair
patterning and brain development occur in tandem while the embryo develops in
utero”(Oke). Equine facial whorls have been and still are a trending topic today,
with many different studies linking behavior, temperament, and handedness. This
exact study aims to “identify a unique link between equine motor laterality, or
‘handedness,’ and specific characteristics of facial hair whorls (trichoglyphs)” (Oke).
Jack Murphy, PhD, from the department of Life Sciences at the University of
Limerick quoted from The Horse states that, “it has long been speculated that most
horses experience some degree of motor laterality in that they prefer one lead (or
side) over the other”. Researchers suggest, “right-handed horses had significantly
more clockwise whorls whereas whorls were more likely to flow in a counterclockwise direction in left-handed horses” (Oke). As horse people know, most
horses have a ‘preferred’ or dominant side to most of it’s gaits, either the right or left
rein, a quick connection could be for example, how humans are dominant with a
3
specific hand. “Despite not knowing the exact embryological explanation for the
association between hair whorls and laterality, knowing of its existence provides an
easily identifiable external characteristic that could be used to predict a horse's
lateral preferences”(Shivley). With that said, trainers and owners can “design
training protocols that use the horse's natural side preferences” (Shivley). We used
two tests to attempt to link the two characteristics together, the first was a grazing
trial where we observed the horses in their natural state, and recorded their
behavior for five minutes at a time. For the second test, we conducted a frightening
stimulus trial using an umbrella. “Most scientists would agree that the way that an
animal behaves is determined both by its genetic make up and the environment in
which it has developed and currently lives” (Randle). Therefore we did all of the
experiment at the same farm, during the same turnout hours that way the horses
were used to their environment and in their current daily routines. The purpose of
this study is to observe the direction of the horse’s hair whorls and determine if the
rotation of their hair whorl and laterality show a connection with one another.
4
Methods & Materials:
For this study we were lucky enough to observe and study some of the
horses at the Bridgewater College Equestrian Center in Weyers Cave, Virginia. We
used a total of eighteen different horses for the experiment, with ages ranging from
ten to nineteen years old. Within the eighteen-horse sample, we had an array of
breed and gender variety; examples from the study are Thoroughbreds,
Warmbloods, Paints, and Quarter Horses. For the sake of our data collection we
wanted to keep all of the horse’s characteristics in order to compare characteristics
like: sex, age, and breed of the horse, but what really mattered for the experiment
are the directions of the hair whorls for each individual horse. Each horse had a
unique whorl and some of the horses had multiple whorls, sometimes even more
than a couple. Out of the sample, only three of the horses had more than one facial
whorl and just one had three (Kona). Of the horses with double whorls, Panda had
two side by side, and Boy had one on top of the other, with that said, neither of the
whorls went in the same direction.
The first way we recorded behavioral laterality of the horses for the
experiment was where we observed the horses grazing for five minutes at a time
out in their pastures during evening turnout hours. Within these five minutes we
kept constant tallies of which front leg they were on the most during the timed
period. In addition to that observation we would also keep track of the length of
time the horse was on each leg to make sure they were on their dominant leg the
most. My research partner and I took turns observing and tallying, while one of us
would record the behavior to use for further research. We wanted to add in another
5
test to our experiment to compare to the grazing trials, so we also did a frightening
stimulus trial as well. Materials used for this stimulus were an umbrella, and a
device to record the horse’s reactions. The umbrella was opened directly in front of
the horse at an appropriate distance and the recorder videoed from the side to
determine the direction in which the horses turned. This gave us an accurate
representation of which side they would naturally take ‘flight’ away from something
scary in the wild or on a daily basis. Depending on which direction they turned (left
or right) gave us a depiction as to which side they were most likely to be dominant
on.
Name
Sex
Age
Breed
# of Whorls Whorl Direction
Andy
G
15
Throughbred
1 Counter
Cassie
M
16
Throughbred
1 Clockwise
Champaign
G
15
Warmblood
1 Clockwise
Cisco
G
13
Paint
1 Counter
Conteazi
G
11
Oldenburg
2 Both clockwise
Cowboy
G
10
Appendix
1 Counter
DD
M
16
Hanoverian/TB
1 Counter
Evie
M
15
Throughbred
1 Clockwise
Kona
G
19
Throughbred
3 2 Clockwise Counter
Millie
M
17
Warmblood
1 Counter
Oliver
G
11
Warmblood
1 Counter
Oreo
G
16
Paint
1 Clockwise
Panda
G
18
Throughbred
2 Clockwise Counter
Raffa
G
15
Warmblood
1 Counter
Sandy
G
19
Warmblood
1 Clockwise
Tyme
G
13
Warmblood
2 Counter and Clockwise
Whimsy
G
19
Throughbred
1 Counter
6
Zenith
G
20
Warmblood
1 Counter
Data:
We used Excel to create graphs and tables with our raw data, below are
descriptions of each individual graph. The first graph shows the direction of the
facial whorl, the horse’s dominant leg while grazing, as well as the direction they
turned during the frightening stimulus. The second graph shows the number of
horses that had a clockwise, counterclockwise, or both directional facial whorls. The
third graph shows the comparison between the two tests, the grazing stance and the
frightening stimulus with the left or right turns or favored limb. The next graph
(fourth) depicts whether test one, or the grazing stance was either accurate or
inaccurate in correlation to the horse’s hair whorl. The fifth and final graph displays
whether the frightening stimulus was accurate or inaccurate depending on the
horse’s direction of turn during the frightening stimulus.
Dominant Leg
Frightening Stimulus
Name
Whorl Direction
Stance
Turn
Andy
Counter (left)
Right
Right
Cassie
Clockwise (right)
Left
Right
Champaign
Clockwise (right)
Right
Right
Cisco
Counter (left)
Right
Left
Conteazi
Clockwise (right)
Right
Left
Cowboy
Counter (left)
Right
Left
DD
Counter (left)
Left
Left
Evie
Clockwise (right)
Right
Right
Kona
2 Clockwise
Right
Right
7
Counter
Millie
Counter (left)
Left
Left
Oliver
Counter (left)
Right
Left
Oreo
Clockwise (right)
Left
Right
Panda
Clockwise Counter
Left
Left
Raffa
Counter (left)
Right
Right
Sandy
Clockwise (right)
Left
Left
Tyme
Counter (left)
Left
Left
Whimsy
Counter (left)
Right
Left
Zenith
Counter (left)
Right
(Did not react)
8
9
Analysis:
Overall, this experiment has made us realize that figuring out a horse’s
‘handedness’ depending on the direction of their hair whorls is somewhat far
fetched. We did two different tests for our experiment and neither of the results
came out to be similar in the end. The first test, or the grazing stance trials showed
us that 6 out of 16 of the horses (did not include Panda or Kona because they had
more than one whorl) had the correct stance depending on the direction of the hair
whorl and in comparison, 10 out of 16 of the horses had the incorrect stance. With
that said, these results either prove that one cannot determine a horse’s dominant
side by their grazing stance according to their whorl or that the dominant leg is not
the fore leg that is forward but that it is the one that is back. In addition, our data
also showed us from the frightening stimulus (second test) that 11 out of 15 of the
10
horses (did not include Zenith because he did not react) did turn the correct way
according to the correlation with their hair whorl and that 4 out of the 15 turned the
incorrect way. Therefore, the results show that the frightening stimulus was much
more accurate when determining the horses more dominant side in correlation to
their hair whorl, than just observing their natural grazing behavior.
Limitations:
At first we had different plans for this experiment, as in we originally wanted
to view each of the horses on a lunge line and record their footfalls in order to
determine their dominant side. We both shortly began to realize that by having the
horses on a lunge line we were interfering with the horse’s natural movement and
behavior. From there on out we opted out that tactic in exchange of just watching
the horses graze for five minutes each and recording which leg they were on, while
also using the frightening stimulus to get a comparable result. There was a good
amount of limitations with test one, the biggest one would be that the horses
wanted to come up to us in the fields instead of grazing so we would have to rotate
from pasture to pasture in order to get results from each horse. To add to that, there
was a low quality of grass in some of the fields (they have round bales) but we
would have to wait until some of the horses found a patch of grass to snack of to
observe their behavior. Lastly, some of the horses would just flat out walk away
from us, and we would have to wait until they settled and began to graze again, and
we recorded from a comfortable position for the horse. The limitations for the
frightening stimulus seemed to be less tedious, for example, Zenith did not even
flinch at the opening of the umbrella, and therefore we just removed him from our
11
study. Another limitation was the position of the ‘attacker’, the umbrella needed to
be opened head on, directly in front of the horse that way if the individual was
positioned off to the left or right it could give the horse a reason to turn to its nondominant side.
Results:
This experiment shows that the direction of a horse’s hair whorl is not
always an accurate relationship of whether they are left or right side dominant.
There are indeed additional ways to do this experiment but Alyvia and I agreed
along with our results, and other current studies that the best way to test it is by
performing some kind of frightening stimulus in a horse’s natural habitat, that way
it can really show their natural dominant side. Likewise, for further results, more
experiments using this tactic or something similar should be tested to continue
determining the correlation between hair whorls and the dominant side of the
horse.
Acknowledgements:
We would like to thank the Bridgewater Equestrian Center Staff for their
cooperation and supply of horses for this study. I would personally also like to thank
my partner, Alyvia Elliott, for the assistance, hard work, and flexibility contributed
to the study.
References:
Oke, Stacey. “Link Between Facial Hair Whorls and Horse ‘Handedness’ Reported.”
TheHorse.com. N.p., 23 June 2008. Web. 27 Nov. 2016.
Randle, H.D., T.J. Webb, and L.J. Gill. "The Relationship Between Facial Hair Whorls
12
And Temperament in Lundy Ponies." Rep. Lundy Field Soc. 52 (n.d.): 67-83.
Web.
Shivley, Chelsey. “Behavioral Laterality and Facial Hair Whorls in Horses…” Journal
of Veterinary Science. N.p., 2016. Web. 27 Nov. 2016.