From the brains behind brains on, this is the moment of um.

Answering those questions that make you go, um, um, um, um, um.

Moment of Um comes to you from APM Studios. I'm Anna Weigel.

Um.

I'm at the dog park with my pup, Cece. We've already done a few laps to say hi and sniff butts. I mean,

Cece does the butt sniffing. I'm more of a hug and chat kind of gal. Anyway, the dog park is

hopping today. There's Pretzel the Golden Retriever chasing Leroy the Doxon. Peanut the Chihuahua

is ferociously guarding her tennis ball. Oh, oh, and Marlene the pug and Toby the St. Bernard just arrived.

Wow, so many good dogs and so many sizes, from Edy BD to, well, St. Bernard's size, which is big.

I wonder why dog's sizes can be so different. I mean, cats come in different colors, but they're

mostly the same size.

So what makes dogs different?

Theo and Wilfred were curious, too.

Why are some dogs so small and others so big?

Good thing I know exactly the right person to

fetch the answer.

Ha ha!

Music The reason. The reason dogs come in so many sizes is because over thousands of years, we've given them a ton of different jobs to do.

My name is Anna Goldfield, and I'm a producer at Brains-on, but I'm also an archaeologist,

and I love talking about things that people did in the past.

I also love dogs.

We're not exactly sure when the first wolves began hanging out with humans, but researchers think it was at least 23,000 years ago, and probably even earlier than that.

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