Just how close can we get to our closest primate relatives? That's the question at the heart of our show Lucy -- a question that we try to answer by getting to know a chimp named Lucy, and a bonobo named Kanzi.

If you've listened to the show, you'll be eager to see the photo Jad mentions of Janis Carter hugging Lucy -- it's in the slideshow below, along with some other powerful shots of Lucy. Plus, take a look at a video of Kanzi using the "symbol keyboard," or lexigram, that Soren describes in the episode.

Slideshow produced by Sharon Shattuck.

And if you want more, check out this video of Kanzi on the Great Ape Trust's YouTube Channel.