Sex and Lies

S1 E2: Charles Darwin was fascinated by the extraordinary behaviour of carnivorous plants and we now know that he barely knew the half of it. Recently scientists have shown that many more plants are carnivorous than we ever thought. Welcome to the world of killer tomatoes and murderous potatoes. But even the more obvious carnivorous plants- sundews, flytraps and pitchers - are revealing new behaviour. Scientists have finally worked out how the Venus flytrap can close its trap so quickly and discovered an underwater relative- the waterwheel plant- that is even more amazing. Pitcher plants sometimes need to form partnerships with insects. Mosquito larvae live inside North American pitchers, where they break up drowned prey and help the plant digest it. But in Borneo, one giant pitcher has formed a remarkable relationship with one species of ant. The pitcher has swollen tendrils, to house the ants. The ants dive into the pitcher fluid to retrieve drowned insects to feed on- but in tearing these up they also help the plant digest the prey.