Artist Sarah Roberts works with millions of tiny helpers: microbes. In Painting with Bacteria, a collaboration with Simon Park, a molecular biologist at the University Of Surrey, she introduced the organisms to watercolours, resulting in swirling paintings blurred with colour. “We are constantly in contact and communication with microbes, but we aren’t really aware of them,” says Roberts. “I wanted to get to know bacteria in a more conscious, direct and visceral way; to approach them as if they were other people or bigger animals – as if we might be able to arrive at something resembling a common language.”

Edinburgh-based Roberts has an interest in biology: her work and influences range from botanical illustration to slime mould. The bacteria project grew from listening to lectures and podcasts such as This Week in Microbiology as she worked. Park, meanwhile, is known for his bio-art projects, most notably growing a book, BacterioFabrication, out of bacteria.

From skyscrapers to bacteria: the best science and tech photography Gallery From skyscrapers to bacteria: the best science and tech photography + 63

+ 62

+ 61

+ 60

+ 59

+ 58


With Park’s guidance, Roberts placed Serratia marcescens – a red pigmented bacteria – on to agar plates previously painted with watercolours. When coming into contact with the paint, the bacteria moved the colours around, essentially becoming artists. “Dr Park and I thought the bacteria would either eat or avoid the paint, but some swarmed through it and moved it about as they went, leaving the story of their movements behind them.” Serratia marcescens was chosen due to its motility; the bacteria moved through the watercolour and agar in a similar way to how it behaves in a natural environment: in a co-ordinated manner.

Painting with Bacteria makes visible a microscopic reality. “As the bacteria swarm, they travel in circular movements, like little children charging around a playground,” says Roberts. “They also rotate as they go, and are covered in long hair-like structures called flagella which help propel them. They’re like millions of tiny little car-wash brushes spinning very quickly.” sarahroberts.net