Small dogs are incredibly cute – if a bit loud – but did you know some are so short that their bellies nearly touch the ground? What are the shortest dog breeds out there, and who is the shortest dog in the world?

Some dogs are big, and some are small – but then there's a category of pooches out there that can only be described as minuscule.

This isn't just a curiosity. We're talking dogs so small that their bodies actually drag along the ground, leaving their fur in a constant state of muddy-matted mess.

It naturally raises some questions. Is it OK for some dogs to be so short, or are we straying into cruel breeding territory? It's time to find out.

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So who holds the animal record for shortest dog in the world? TAG24 takes a look at the heights of some of the tiniest doggos, and dives into some of the world's shortest dog breeds.

"Miracle Milly" was born in December 2011 and is the world's shortest dog, according to Guinness World Records. Weighing only a pound, she overtook the previous record holder Boo Boo, who was 4 inches tall. She's from Dorato, Puerto Rico and loved by her faithful owner Vanesa Semler.

This beautiful, tiny little doggo is so small that her height has been noted all over the world, with articles in the Huffington Post, on Fox News, and all over the place celebrating her smallness. Looking at her, you wouldn't be surprised, she sure is tiny! But how short is she really?

Milly is a tiny little chihuahua, one of the smallest dog breeds in the world. Like most chihuahuas, she is a friendly and excitable little doggo, full of energy and personality. On average, chihuahuas generally grow to be about six pounds in weight, making it particularly impressive that Milly comes in at only a pound!

As the shortest dog in the world, it won't surprise you that Milly stands at 3.8 inches in height. This comes just below her closest competitor, Boo Boo, who measured in at 4 inches, and makes her so tiny that her cute little face barely reaches the top of the grass leaves!

There are many dog breeds that stand so far below our knees that we find it hard to believe they can walk at all. Others might not be particularly small, but have such short legs that you wonder how their ankles can stand the weight of their torso. Oh, and how do they keep their bellies off the ground?

Here are some of the shortest dog breeds in the world:

• Pomeranian
• Yorkshire Terrier
• Chihuahua
• Pekingese
• Tibetan Spaniel
• Norfolk Terrier
• Havanese
• Japanese Chin
• Shih Tzu
• Corgis
• Basset Hound
• Dachshund

Breeding can be a cruel and unnatural thing. Many cross-bred dogs are made to be cute rather than practical or even healthy. They're tiny little cuties, capable of fitting in a purse, and constantly rubbing their belies across the floor. Dachshunds are so short because they were bred for digging and hunting, but others are bred short for the aesthetic.

In other words, dogs don't need to be short and, in general, it is unnatural for them to be so. Instead, the height of a dog is often determined as an aesthetic choice during breeding. Whether that is ethical is, at best, questionable.