-Animals come in all different sizes, including our pets.

They take different-size steps, need different amounts of food, and we can use numbers to show just how much.

Guinea pigs are little.

But how little?

To figure that out, we can use a tool called a measuring tape, which marks off equal distances called inches.

Those numbers tell you how many inches you're measuring.

Marshmallow here is just 10 inches long.

And Brownie tells us she's about the same.

Cats have four legs, just like guinea pigs, but they are bigger.

Titan here is small for a cat, but if he would just let us measure him, we find that he's 14 inches long without his tail.

When you get to dogs, the different breeds, or types, of dog all have their own special look and can be really small, really big, or anything in between.

The official way to measure a dog's height is from the floor up to the shoulder.

Dobby, who we think is part hound, stands 12 inches tall.

And Goose, who is part terrier, is just a little taller, at 15 inches.

Rhea is part Schnauzer, part Labrador, which are both bigger dog breeds.

She is 21 inches tall.

That's a lot more than Dobby and Goose.

By the way, see how you can measure going either up or down?

You still get the same length.

Of course, you have to hurry up, before the measuring tape gets eaten.

You can measure the length of your dog, too, from the nose to their rear end.

You don't count the tail.

Lucia, who is a Jack Russell mix, is 21 inches long.

That's twice as long as Marshmallow the guinea pig.

Homer, our boxer, is even longer, at 30 inches.

And Dax the chocolate Lab is way bigger, at 42 inches -- maybe from eating all that peanut butter.

If you count out 12 inches for every foot, he's 3 1/2 feet long.

That might be as long as you are tall.

So it's no surprise that animals weigh different amounts, too.

Once again, the guinea pigs have the smallest values.

Marshmallow weighs just 35 ounces, and Brownie's a little chunkier, at over 40 ounces.

There are 16 ounces in 1 pound.

So when we get to bigger pets, we measure in pounds.

Titan the cat weighs just about 5 pounds.

Rhea weighs 33 pounds, and what's funny is little Dobby weighs 1 pound more than that.

He must be working out those muscles.

But Dax the lab really tips the scales.

Wow!

He's 84 pounds.

Sure enough, Dax also eats way more food than these others.

Here are all our pet stars nibbling on their snacks with very good manners, while Dax just wolfs down his food.

Do you think Dax eats more than you do?

What we do know is you probably want to eat your own food, not his.

Yes, Dax, now you can have dessert.