Pollia Condensata: The Shiniest Living Thing on Earth
Deep in the Ghana forest, there’s a plant that grows the shiniest fruit in the world. The brilliant blue fruits come from Pollia condensata and are actually the shiniest living thing of any kind, according to a new study.
The fruits are iridescent; like soap bubbles or the back of a CD, their color changes as you observe them from different angles. Iridescent features don’t actually contain pigment. Instead, they rely on a particular physical cell structure to reflect other colors. While it’s fairly common for animals like butterflies and birds to have iridescent features, and it can also be seen in certain rocks and shells, it’s extremely rare to see iridescence in plants.
A researcher from the University of Cambridge discovered the plant while searching for species that bend light. She studied a specimen at Kew Gardens in London, which had been been collected from Ghana in 1974. Because the amazing color of the fruit comes from the physical structure of its cells, rather than a chemical pigment, it doesn’t fade over time. The decades-old fruit was just as shiny as it was when it was in 1974.
The fruit produces its iridescence through complex layers of cells, each running parallel to the one above but slightly rotated, producing a spiral. As light hits the cells, some of it is reflected off each layer. The layers amplify the effect, producing extreme brightness.
Why so shiny? For animals, iridescence helps attract mates, distinguish between species and sexes, avoid predators, and possibly help in guiding flocks of birds. For the Pollia plant, the purpose behind the bright color remains unclear. Researchers theorize that the plant is trying to mimic a neighboring fruit. Pollia is dry and provides little nourishment, while the neighboring berry is tasty. The researchers think another possible explanation may be that birds are attracted to the shiny fruit to decorate their nests or even use in mating displays.
Main photo credit: Vignolini, Rudall, Rowland, Reed, Moyroud, Faden, Baumberg, Glover & Steiner