In this episode, we dive into the world of rats. Sure, they can crawl up sewer pipes into your toilet and may have been at least partly responsible for the deaths of tens of millions of Europeans. But - they're also really smart, feel regret, and can show emotion with their ears.  This is a special episode. In our first half, we share cool rat facts. And in the second half, we interview Professor Monica Green, who studies plague. We learned so much from her about plague, how it was spread, and even that it is still around today.  We couldn't fit our whole interview with Professor Green into this episode, so we're including a longer interview on our feed. You should see it right behind this one.  Thanks to our Patreon sponsor Henry for getting us excited about rats! If you'd like to be a Patreon sponsor, please click here: https://www.patreon.com/coolfactsaboutanimals