Some dogs just look like they're smiling all the time - but that huge grin on their face may not actually mean they're happy.
Dogs express their emotions differently to humans, and a lot of the time, we read their body language wrong.
Carolyn Menteith, head canine behaviourist at tails.com, told The Mirror : "Without doubt our dogs can smile.
"Unlike us however, they don't usually smile with their mouths. Showing all your teeth in dog language doesn't usually mean happiness.
"That's where we can get confused when we interact with our dogs… we forget that dogs talk just as loudly as we do, and show their emotions just as clearly, but they do it very differently."
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How do dogs smile?
Carolyn explains that dogs smile "with their tail" because "when a dog is happy, it shows in their body language."
"We tend to be verbal and audible about our emotions, whereas dogs communicate with us using their body language and often fairly subtle physical gestures that bypass people who haven't learnt how to 'speak dog'," Carolyn says.
"Once you know how to 'speak dog', you can tell exactly how your dog is feeling - whether they are worried, fearful or ecstatically happy.
"When a dog smiles, their tail is relaxed but waving (or in some breeds or individuals, wagging crazily), their eyes are soft, their ears relaxed and their body is often wiggling with their happiness."
Can dogs laugh?
"Dogs show their emotions mostly through their body language and not with words, vocalisations, or indeed, with laughter," Carolyn explains.
"Some dogs are noisier than others - just like people - and so if they get really excited and playful, they might well bark, yip, or even huff - especially in an attempt to get another dog or a person to play - but this isn't laughter.
"Interestingly however dogs do seem to recognise laughter in humans and know that it is positive - and some dogs seem to go out of their way to encourage their owners to laugh."
So if you've ever thought your dog is doing something to make you giggle - they probably were.
Does your dog do anything super silly? Email nia.dalton@reachplc.com.
