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| EXPLORE | ANIMALS
SO THAT’S WHY
THE LONG FACE
By Jeremy Berlin
Let’s face it: When it comes to expressions,
a horse is no one-trick pony.
Recent findings have revealed that our
equine friends use 17 discrete facial
movements to communicate. That’s 10
fewer than humans—but one more than
dogs and four more than chimpanzees.
Researchers at the University of Sussex
discovered this by dissecting a horse
head and identifying the musculature
below its facial features. Then they
watched behavioral footage—15 hours
of video showing 86 male and female
horses, from a variety of breeds, ranging
in age from four weeks to 27 years.
The last step was to use a tool called
EquiFACS (Equine Facial Action Coding
System) to catalog the eye, lip, nostril, and
chin movements they’d observed. The
result: a gestural map that suggests evolutionary
parallels among varied species.
Jennifer Wathan, the study’s lead
author, says the similarities between
horse movements and human ones are
striking. They include raising inner eyebrows
(“puppy-dog eyes”) to show fear,
surprise, or sadness; pulling back lip corners
(smiling) in greeting or submission;
and opening eyes wide to indicate alarm.
Wathan says these findings can help
us better understand interspecies relationships.
Systems like EquiFACS “create
a common language to objectively make
comparisons across species—even those
with totally different-shaped faces.”
Her team’s research, which is already
helping veterinarians and trainers, could
also connect facial expressions to emotional
states. “We don’t know much
about the emotional lives of animals,”
she says. “What does a positive emotion
look like? This tool could help us see it.”
An Arabian horse looks
around its stable in the
United Arab Emirates.
Horses are visual animals—
they see better than cats
and dogs—with communication
skills that evolved to
keep family groups together.
PHOTO: TIM FLACH