New York Public Library

A new pair of "cat" and "dog" bots on Twitter are doing something much more wonderful than tweeting just pictures of cats and dogs.

Meet the aptly named NYPL Cats and NYPL Dogs, two bots built by Ashley Blewer, who's an Applications Developer at the New York Public Library. Cats is older than dogs by a couple of weeks, but they've both been around for a bit over a month and both tweet 4 times a day. Here's how each bot sprang into existence:

But, this is what their tweets normally look like:

The images only partially embed (as links, so you have to click on individual tweets to see a snippet), but they're well worth digging through. They're especially fun to explore since the bots are pulling from images in NYPL's digital collection that include the words "dog" or "cat" in their title, which means that while often the bots spit out images of cats or dogs like these:

"'Laika,' the Sputnik dog."

New York Public Library

"Cat reaching into a jar."

Adolf Oberländer/New York Public Library

Or parts of G.E. Studdy's "Bonzo Dogs" collection of cigarette cards:

Or this picture of a "Cat with cocktail":

They also produce a lot of images you might not expect from a cat or dog bot, like this print of "Kra, or Dog-like Macaque":

Or this photo from a 1965 rehearsal for a play called Drat! The cat!

New York Public Library

Or this illustration of a "Lesser Spotted Dog-fish."

Seems friendly, right?

What's most exciting about Twitter bots (or bots in general) is when they act serendipitously. It isn't a bot fulfilling its exact purpose that's great, but when it breaks from it and delivers something you don't expect. NYPL Cats and NYPL dogs do that regularly. You go in expecting dogs and cats, and emerge with theater photos or weird cartoons or fish illustrations. It's a bot that tricks you with its parameters.

Plus, sometimes you just get some great dog illustrations.

More of these, please.

Ethan Chiel is a reporter for Fusion, writing mostly about the internet and technology. You can (and should) email him at