(Note: See update below)
Recently, the study of “swirlology” has come to the forefront of analyzing facial hair whorls and forelimb preference in horses. Previously considered a “pseudoscience” without facts to back it up, several studies have been conducted to put data behind the theories and prove that a very small patch of hair can have a very large influence on the forelimb preference of a performance horse.
What’s so special about this small, circular patch of forehead hair located between a horse’s eyes? Plenty, according to researchers. When an equine fetus is in the early stages of development, the facial whorl hairs are the first to develop, forming when the skin stretches across the forehead. These hairs are directly connected to the brain; all other hair on the body grows from follicles.
The study of “trichoglyphs” – scalp hair whorls and handedness in humans – has been present in pediatrics for years. Only in the last few decades has the process progressed to mammals. Let’s look at some of the studies that involve equines, keeping in mind that facial hair whorls and forelimb preference is still being studied by scientists and the findings are always in a state of flux.
In 1994, the hair whorls of 133 Grand Prix jumping horses at the Masters at Spruce Meadows in Calgary were studied. Many horse breeds were included in this study, as the competitors were from 15 of the world’s top show jumping countries at that time. The FEI provided the researchers with the performance data and ranking of each horse. Although a definitive correlation between whorls and forelimb preference wasn’t established with this study, an important finding was unearthed: the behavioural influence of double hair whorls on the performance horse.
Champion show jumper Big Ben was found to have a double hair whorl, which is not unheard of but is rare, as only 16 percent of all equines have them. In the instance of double whorls, one facial whorl is usually set higher than the other, with the higher whorl displaying the forelimb preference and the expression of strong behaviours, which are not always in cooperation with the rider. Horses with a double whorl combination tend to be more emotional and reactive than average, something Ian Miller can attest to, having described riding Big Ben as “like being on a skittish elephant.”
In 2007, researchers observed 219 Thoroughbreds and Thoroughbred/Irish sport horses in training at eight different facilities in southern Ireland. Participating were 21 stallions, 104 geldings and 94 open mares between four and six years old, all in regular ridden work. Trainers recorded their observations of natural forelimb preference in each horse at the walk, canter, and jump. Researchers then analyzed the data reported by the trainers, factoring in each horse’s single hair whorls with their natural forelimb preference.
The results yielded 104 horses with facial whorls in a counter-clockwise direction preferring the left forelimb, while 95 horses with a clockwise direction preferred the right forelimb. Furthermore, the male horses preferred their left forelimb (73 compared to 39) whereas the mares displayed right forelimb preference (56 compared to 31). The remaining horses did not display a forelimb preference.
In 2005, Australian researchers conducted two separate observation studies comparing three breeds of performance horses with forelimb preference while grazing. The first consisted of 106 Thoroughbreds, and the second utilized 40 Standardbreds and 40 Quarter Horses. As limb preference gets stronger with maturity and training, young, untrained animals of each breed were included in the study as well.
Overall, there was a left forelimb preference in 43 of the Thoroughbreds; 10 horses exhibited right forelimb preference, and 53 did not have a preference. Standardbreds also showed a left forelimb preference; 16 compared to five with a right forelimb preference; 19 had no preference. Of note, the Quarter Horses were almost totally ambidextrous with 33 of the 40 having no forelimb preference; four preferred the left foreleg and three the right. Although no facial hair analysis was performed during this study, it did show that there is that there is significant forelimb preference, or lack of one, between breeds.
What all this means to riders
As equestrians, instructors and trainers, what are all these studies telling us? First, the sooner a young prospect is evaluated for forelimb preference, the sooner a specialized training program can be developed to produce a well-balanced performance horse before emotion, time and money are invested in an animal. Secondly, when the analysis of a horse’s hair whorl is factored into natural forelimb preference, certain behavioural characteristics can occur that can be anticipated by a rider in the ring or on the course.
A 2015 Colorado study established a correlation between facial hair whorls and the direction a horse turned when an umbrella was suddenly opened outside the arena they were in. Ten geldings and nine mares, consisting of 12 Arabians, three Thoroughbreds, and four Warmbloods were used in this study. Of the 17 horses, 12 had a clockwise facial hair whorl, and the remaining seven horses had a counterclockwise whorl.
The direction each horse turned in response to being startled was recorded, then compared to the direction of their facial hair whorls. The horses with clockwise facial hair whorls turned to the right (53 percent) and the horses with counterclockwise facial hair whorls turned to the left (47%). In addition, researchers found that a horse with a hair whorl off-center to the right of facial midline tended to turn to the right, and a horse with a hair whorl to the left of midline turned to the left.
Facial hair whorls are not a predictor of behaviour, but they can factor into a horse’s predisposition to natural forelimb preference. As more studies emerge and research is further validated, that small patch of forehead hair may become an invaluable aid in assessing a young prospect for your riding discipline or helping you to better understand and enable your current athlete.
*** UPDATE ***
In a recent study entitled Comparing Equid Skulls for Insight into Behavioural Differences, Professor Katrina Merkies Associate professor and University of Guelph researcher Dr. Katrina Merkies collaborated on a project with professor of animal behaviour and animal welfare science at the University of Sydney, Paul McGreevy and Georgios Paraschou, veterinary pathologist at the Donkey Sanctuary in the UK. They took various measurements comparing the skulls of standardbred horses to those of donkeys and found that their olfactory bulbs differed in both size and placement.
The olfactory bulb (structure in the brain important to the sense of smell, learning and memory) in donkeys was smaller than horses and rotated toward the centre of the brain. The differing size and location raise questions as to whether horses may pick up on a wider range of odours than donkeys. Future studies may also reveal how equids differ in processing external stimuli and in their social responses (two of many functions associated with olfactory functions).
“An unexpected discovery came up pertaining to the placement of whorls,” said Merkies. The study revealed that whorl placement in horses almost always corresponded with the location of the olfactory bulbs. Not so in in donkeys where the hair whorl was located much further down the nose. There may be something to the folklore on whorls, which implies a whorl above the eyes denotes a difficult horse, one between the eyes suggests a manageable horse, and one below the eyes is the sign of a clever and calm horse. “The Donkey’s whorl below their eye line matches their known calm temperament,” says Merkies.
Merkies hopes the study results may be linked to other documented differences between horses and donkeys, particularly when it comes to differences in behaviour. Predictors of behaviour could mean better selection of equids for the jobs they are intended for thus improving communication, safety and welfare for all involved. ~ Equine Guelph