Discussion: The Gherkin’s shape, structure and ventilation scheme were all inspired by a kind of sea creature known as a glass sponge. They have delicate, elongated exoskeletons. They filter nutrients from water they suck in at their base and expel from a hole at the top. In this way this tower circulates air.Ask students what they think the models (on the right) were made for.These models were made by Foster + Partners to work out the best shape for the 180-metre high office building in the City. They modified them to take into account the bulk, visual impact and aerodynamic qualities of the building, also the provision of open space at ground level. They show how buildings of different shapes can have equal volume. The missile shape appears more slender than a rectangular block of equivalent size. It allows air to flow around the building rather than being deflected towards the ground. This reduces wind loads and makes it less windy for pedestrians at ground level. These models can be seen in the V&A+RIBA Architecture Gallery.The Gherkin (30 St Mary Axe) was designed by Foster + Partners and completed in 2003. Designed as an office building with a restaurant, it has become one of London’s most iconic structures and has made a striking impact on the city skyline.Extension activity: design challengeGive each student a piece of plasticine and ask them to divide it into two equal parts. Model each part into a unique abstract shape; one shape could be inspired by choosing a word as a starting point (e.g. sustainable, temporary, organic, tactile, atmospheric, introvert, extrovert, energetic, beautiful, calm, simple, grand, ornate, contemporary, historic, futuristic, traditional). Use one of these shapes to inspire a design for a lamp or piece of furniture, use the other to inspire a design for a building