Have you ever wondered why your furry friend’s eyes look so eloquent? Delve deep into the fascinating world of canine evolution and learn how our canine companions came to be. We explore how they developed the iconic “puppy eyes” that captivate us.
Humans have selectively selected for traits in dogs as they became domesticated. This includes the ability to make facial expressions. Scientists have shown that dogs developed muscles around their eyes that were not present in their gray wolf ancestors. These muscles allow dogs to raise their eyebrows and create “puppy eyes.”
Continuing research into the evolution of facial expressions in dogs is uncovering why these muscles developed and helping us further understand the human-canine relationship.
created over thousands of years
The symbiotic relationship between domestic dogs and humans dates back more than 30,000 years. Early wolves benefited from humans by eating leftover meat from hunts, but humans took advantage of their fellow wolves’ ability to find prey faster, protect them from predators, and transport supplies.
Wolves were selectively favored because they had physical and behavioral characteristics that were advantageous to humans, and those characteristics were passed down through generations. Over time, they became even more popular, resulting in the domestic dog we know and love today.
build a bond
Although domestic dogs and gray wolves are closely related genetically, dogs have several traits that have evolved to support their bond with humans. Many of these encourage Eye contact and mutual gaze.
For example, a human and a dog look at each other. produces oxytocin (‘love hormone’) in a feedback loop that is not observed between humans and wolves. Researchers artificially induced oxytocin in dogs to better understand its relationship with eye contact with humans. Dogs that received oxytocin made more attempts to make eye contact with humans than dogs that did not receive oxytocin.
Dogs use eye contact with humans to let someone know you need help. This behavior is much less likely to occur in wolves. for example, dog puppy tries to make eye contact faster than hand-raised wolf puppies. Additionally, wolves that have been raised by humans do not exhibit the evasive or aggressive behavior toward humans.
Evolution of puppy eyes
Scientists note that this eye contact in dogs with humans is often accompanied by. By facial expressions. There is also an expression that creates “puppy-like eyes” by raising the eyebrows. And as any puppy parent will tell you, what a powerful statement that is.
a 2013 survey A study of 27 rescue dogs found that dogs that gave puppies their eyes more often were adopted sooner. This suggests that humans may prefer dogs with this facial expression.
a 2019 survey The facial muscles of six dogs and four wolves were examined. Wolves can raise their eyebrows, but the force and frequency is much lower than that of dogs.
Dogs make eye contact with humans to let them know they need help.
Researchers found differences in two muscles around the eye that help explain this observation: the levator angularis medial (LAOM) and the levator angularis lateralis (RAOL).
LAOM is located above the eyes towards the nose and lifts the eyebrows. This muscle is highly developed in dogs. However, in wolves, it is just a set of small muscle fibers that are sometimes blocked by a tendon that is connected to another muscle called the orbicularis oculi.
RAOL pulls the corners of the eyes back toward the ears. This muscle was found in five of the six dogs and three of the four wolves tested. When present, RAOL was made up of thinner fibers in wolves than in dogs. One dog without RAOL was the Siberian Husky, an ancient breed more closely related to wolves than other dogs studied. This may explain why RAOL did not exist.
What makes a puppy’s eyes move?
There are several possible reasons why puppy eyes are a feature chosen by humans.
Clearer communication
One of the main ideas is that it is possible through puppy eyes. Dogs will be able to communicate better with humans.
Humans naturally focus on their eyes and the upper half of their faces during social interactions. Expressions in this area, such as raising the eyebrows, convey information and help convey intent and emotion. Humans may have chosen movements of similar parts of dogs’ faces.
a study They investigated the communicative ability of dogs to raise their eyebrows by testing the effects of human attention and the presence of food on the facial expressions of 24 dogs. They found that dogs that received human attention made more facial movements than dogs that did not, regardless of whether food was present. This finding suggests that facial movements made by dogs are active attempts to communicate with humans.
emotional connection
Research supports the idea that dogs can express emotions through unconscious facial expressions. Puppy eyes can be a reaction to your dog’s emotional state. Puppy eyes resonate with humans because they resemble the way humans look when they’re sad. Dogs that appear to be sad may have been chosen because of the sympathy they received from humans.
meanwhile Research shows that dogs don’t make facial expressions like humans, the study We showed that humans and dogs can correctly interpret each other’s emotional expressions.
How to seek care
According to research, Humans prefer dogs with large foreheads and eyes.. This may be because these same characteristics are also associated with infants. Dogs with large foreheads and eyes are perceived as younger and more vulnerable and are more likely to get sick. I was spoken to on the pitch. Used in young children.
Puppy eye expressions exaggerate the forehead and eye size, emphasizing infant-like features. This may lead humans to choose dogs that develop puppy eyes and raise them.
Puppy eyes resonate with humans because they resemble the way humans look when they’re sad. Dogs that appear to be sad may have been chosen because of the sympathy they received from humans.
cooperative eye hypothesis
Visible white space allows humans to determine the direction of gaze and infer cues. This improves communication and cooperation and has played a major role in human evolution.
in the study By comparing stuffed animals with and without visible white space, we found that humans prefer stuffed animals with visible white space. Puppy eyes, which feature exaggerated white areas, are consistent with this preference and may be another reason why dogs use this expression.
promote eye movement
2021 Survey We conclude that raising eyebrows in dogs primarily serves the purpose of aiding eye movement. Researchers counted the number of times 21 dogs raised their eyebrows, both in the presence and absence of humans.
Dogs raised their eyebrows less frequently in the presence of humans, and eyebrow raising was rarely observed without simultaneous eye movements. The authors suggested that the reduced frequency of eyebrow movements in the presence of humans may be due to dogs focusing on humans and not shifting their gaze. Alternatively, the dogs moved their gaze more often when humans were not present, and raised their eyebrows more as a result.
multiple correct answers
All of the above possible reasons have one thing in common: they strengthen the relationship between humans and dogs. One factor may be the most significant, or multiple factors may have contributed to humans’ preference for puppy eyes over time.
Canine anatomy and human co-evolution
muscles are important
Learning more about how and why puppy eyes develop can help humans better care for dogs and provide insight into the evolution of humans and dogs.
One factor may be the most significant, or multiple factors may have contributed to humans’ preference for puppy eyes over time.
Research suggests multiple reasons behind puppy eyes. These may be used to communicate with humans, unconsciously express emotions, facilitate eye movements, or a combination of these elements. Knowing the purpose of a puppy’s eyes can help humans better understand and respond to their dogs, and can further strengthen the bond between them.
Finally, the anatomy that shapes facial expressions does not change easily throughout the evolutionary process. Dogs are an exception because they co-evolved with humans. Studying facial muscle development in dogs can help scientists better understand the connections between emotions, brain processes, and facial expressions, which could be applied to research in other species. There is a gender.
beyond the eyebrows
Previous research continues to support the strong human preference for facial expressions.
In a recent study, Fast-twitch fibers make up 66-95% of the fibers in your dog’s face.However, in wolves it is only 25%. Slow-twitch fibers are responsible for endurance movements, while fast-twitch fibers are responsible for the quick and explosive movements needed for facial expressions.
Whatever made puppy eyes resonate with humans in the first place, there’s no doubt they’re here to stay.
Featured image: Sonsam (via iStock / Getty Images Plus)
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