What dogs see, hear and eat: 3 surprising new discoveries

You may think you know your dog pretty well. But while that familiar face might be easy to read when dinner is late or a walk is overdue, scientists are still discovering just how dogs perceive the humans and objects around them.

Recent studies suggest our canine companions may be capable of connecting a person’s voice with their age, associating particular sounds with visual shapes, and even developing a taste for an unusual new source of protein.

Here are three intriguing recent discoveries about man’s best friend.

1. Dogs may connect a child’s voice with a child’s face

Can your dog tell that a child’s voice belongs to a younger person before seeing who is speaking?

Researchers recently tested 69 pet dogs by playing recordings of either an adult woman or a young girl before showing them a photograph of an adult or child. Sometimes the voice and face belonged to the same age group; sometimes they did not.

The dogs showed a tendency to look longer when voices and faces matched. Intriguingly, this pattern appeared stronger among dogs that had lived with young children.

Scientists, however, describe the evidence as tentative: the overall effect was weak, and the dogs behaved differently from what researchers originally predicted. As such, the finding cannot yet be taken as proof that dogs neatly sort humans into “child” and “adult” categories.

Still, dogs are already known to combine information from different senses when interpreting people, including clues involving emotion and identity. This latest research raises the possibility that everyday experience with children might also teach them something about what younger humans look and sound like.

2. ‘Bouba’ may look round – even to a dog

Try saying the words “bouba” and “kiki”. If asked to match them with two imaginary shapes, many people instinctively pair “bouba” with something round and “kiki” with something sharp and spiky.

This concept – which has been around since the 20th century – is known as the “bouba-kiki effect”. Scientists once wondered whether it might be closely tied to human language.

But dogs, apparently, may be in on it, too: researchers at the University of Parma in Italy tested 70 adult dogs, showing them rounded and spiky shapes while repeatedly playing the sounds “bouba” or “kiki”.

The dogs spent more time looking at the rounded shape when they heard “bouba”, and at the spiky one when they heard “kiki”. A second group was tested while their owners wore headphones, helping researchers rule out the possibility that humans were unintentionally influencing their pets.

The findings suggest the connection between certain sounds and shapes may not be uniquely human – or even dependent on language.

Exactly why the brain makes these connections remains an open question. But next time you tell your dog something is “kiki”, don’t be entirely surprised if he expects it to have pointy bits.

3. Dogs may enjoy kibble made with microbial protein

The future of dog food may contain an ingredient that sounds considerably less appetising to humans: protein produced by microorganisms.

A recent study tested dry food containing 10% microbial protein on 30 dogs, alongside a comparable diet using conventional protein sources.

Given a choice between the two over four meals, the dogs showed a significant preference for the microbial-protein food. They consumed more of it overall and were also somewhat more likely to approach and begin eating it first.

Cats were included in the research, too, and showed a similar preference.

Microbial protein is being explored as an alternative ingredient partly because it can be produced in controlled systems without relying as heavily on conventional animal agriculture.

But the researchers stressed that their experiment looked only at short-term food preference. It does not demonstrate that such diets are better for pets, nor does it establish their long-term health effects.

The study was also conducted by researchers affiliated with MicroHarvest, the company that produced the microbial protein, making independent follow-up particularly important.

Taken together, the studies don’t suddenly reveal what’s going on inside every dog’s head or food bowl. But they do suggest that behind those familiar puppy-dog eyes lies a sensory world scientists are only beginning to understand.

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