Tim Dowling learns about the future of linguistic diversity around the world. With thousands of languages projected to die out over the next 100 years, guests Ghil'ad Zuckermann and Julia Sallabank explain how languages can be revitalised.

Tim Dowling finds out what makes people left-handed. Also what advantages and disadvantages left-handedness can bring. With Professor Chris McManus and Ed Wright.

Tim Dowling learns about the Planet 9 theory from one of its originators Professor Konstantin Batygin. The theory is that way beyond Neptune and Pluto, on the outer reaches of the Solar System a 9th planet, 5 times the mass of Earth is orbiting the Sun once every 10,000 years. We also hear from Professor Samantha Lawler, who is not as convinced by the evidence for the existence of Planet 9.

Tim Dowling speaks to three of the leading dog cognition experts in the world to learn all about dog intelligence. He attempts to find out how smart are dogs compared to other animals? How smart are the worlds smartest dogs? And how smart is his dog?

Introduction to Tim Dowling's new podcast Insult My Intelligence.