So... can we talk to animals? We look back at what we can learn from the ape language research experiments, and what it says about humans. Learn more about your ad choices. Visit podcastchoices.com/adchoices

Koko addresses the world at the Paris Climate Conference - and she is not impressed with humankind. And when she passes away a few years later, her legacy is uncertain, and often hotly contested. Learn more about your ad choices. Visit podcastchoices.com/adchoices