The 'glittery eyes' of domestic dogs are not due to evolution

New findings confirm that large, compassionate 'puppy dog ​​eyes' did not just evolve in domesticated dogs to attract humans as scientists previously thought.

Correspondent in Africa reports that a recently published study sheds more light on the evolution of dogs , dispelling the belief that the sparkling and emotional eyes of puppies are a product of domestication. chemistry.

 An African wild dog in a wildlife reserve in Gauteng province of South Africa. (Photo: Hong Minh/TTXVN).

This study also refuted a previous study in 2019 that hypothesized that dogs have evolved highly expressive faces due to their long history of living with humans.

The new discovery, titled 'Social adaptations in the facial expression and ear muscles of African wild dogs' published in The Anatomical Record Magazine, confirms 'puppy eyes' are large and suggestive of compassion did not just evolve in domesticated dogs to attract humans as scientists previously thought.

Instead, research shows that other species in the canine family are just as likely to produce sad eyes as domestic dogs.

Previous research papers published in 2019 and 2022 hypothesized that dogs develop new muscles around their eyes specifically because this facilitates more effective communication with humans .

But a new study has debunked this theory, finding that other dog species have similar muscular adaptations that allow them to display sad-looking expressions.

African wild dogs have well-developed facial muscles similar to the "puppy eye" expression seen in domestic dogs. (Photo: Hong Minh/TTXVN)

Previous research has compared the facial muscles of domestic dogs with those of wolves (Canis lupus) to find that dogs develop specialized muscles around the eyes to create a wider range of facial expressions.

Scientists concluded that these muscles may have developed when dogs began living closer to humans so that they could imitate our facial expressions as a way of encouraging us to care for them.

In the new study, scientists dissected a dead African wild dog (Lycaon pictus) specimen donated by a zoo and discovered that the animal also had the same 'puppy eye' muscles.

These facial muscles are not unique to wild dogs but have been shown to be as well developed as those seen in their domesticated cousins.

Additionally, several facial muscles in the African wild dog appear to aid in the skillful control of its characteristic large, floppy ears.

'This pattern suggests that visual facial expressions contribute to pack communication in wild dogs and are not unique to domestic dogs,' the researchers wrote in the study.

Lead author of the study Heather Smith from Midwestern University (Illinois, USA) said: 'African wild dogs have well-developed facial muscles similar to the "puppy eyes" expression of domestic dogs!'

Researchers believe these eye muscles evolved to help African wild dogs coordinate and communicate as they hunt on the open savannah.

Like wolves and their domestic cousins, African wild dogs are highly social, living in groups of about 5-9 individuals.

Their highly expressive faces may allow them to produce silent visual signals on grass surfaces.

In the future, Smith and her team hope to examine the facial anatomy of other wild canids, such as foxes, wolves and Asian wild dogs, to see how their puppy eye muscles develop. how good.

This will help them better understand how these species communicate and hunt, and help researchers determine whether this trait exists in species that are both social and visually oriented. Are not.

Adam Hartstone-Rose, a comparative morphologist at North Carolina State University who was not involved in the new study commented: 'This study confirms that not only are [wild dogs] highly social but they are very Many of those social signals may involve visual signals.'

According to Mr. Hartstone-Rose, despite also living in tight-knit social groups, wolves' facial muscles may not have evolved to be as strong as domestic dogs and African wild dogs because they rely less on verbal communication. image.

Wolves hunt in a variety of landscapes, including jungles and mountains, where individuals are more likely to be obscured by rocks or trees in pursuit of prey. As a result, they may have evolved to coordinate using more complex sounds or scent signals instead of visual signals.