Bat Tower in East Otto, New York, USA by Joyce Hwang

Thanks to human-caused climate change, many scientists argue that the world is entering the sixth mass extinction in its history. Bats are among the species under threat. Over a million have died in the USA, where they have succumbed to a fungal infection, and in the UK, bats are vanishing as they lose their habitats and food supply thanks to non-porous buildings, pollution and pesticides, despite being protected by law. One way to mitigate these problems is to provide roosts that compensate for increasingly inaccessible roof spaces, an unintended consequence of building codes meant to reduce heat loss. These artificial roosts usually take the modest form of boxes, but American designer Joyce Hwang has created a monumental bat skyscraper, which also functions as effective propaganda for the pro-bat cause. Hwang is keen to communicate the beneficial activities of bats, which help pollinate plants and control pests, and her zigzagging wooden tower, its base planted with insect-attracting herbs, broadcasts the presence of these easily overlooked creatures to passers-by.