In 'How do they do it?' biologist Gerda takes children into the animal kingdom to teach them about animal reproduction in a light-hearted way. Two teams of two candidates each compete in the game for the Big Golden Mating Trophy. Each episode focuses on one animal. At the start of the quiz, the candidates have to guess which animal it is by taking a crap. Then, based on quiz questions, biologist Gerda takes the viewer and candidates into the wonderful world of the animal's mating ritual: from seduction to the deed! Also in each episode the game 'Piemeltje Prik' is played, Gerda's own variant of the well-known Ezeltje Prik. In this game, teams must guess the location of the male genitalia of animals such as ducks, dragonflies & blue whales. During the quiz, Gerda is assisted by assistant Robbie (Niek Barendsen).