“If I don’t have red, I use blue” Pablo Picasso
One of the most glamorous seeds I know is that produced by the Traveller’s Palm. The plant is related to the South African bird of paradise which produces seeds with bright red appendages. The seed appendages of the Madagascan traveller’s palm, however, are a remarkable shade of blue; they’re as bright as sapphires.
Red seeds and fruits are relatively common in nature, particularly among bird-dispersed species, but blue is exceptionally rare. The reason the Traveller’s Palm has evolved blue seeds is linked to its biogeography. There are few fruit- and seed-eating birds on Madagascar, and instead, this species has evolved a mutualistic relationship with lemurs. Lemurs’ vision can only differentiate shades of green and blue, unlike the vision of birds. Lemurs are therefore attracted to the bright blue, edible appendage of the Traveller’s Palm’s seeds and disperse them – to the advantage of the plant.
Dr Chris Thorogood is Deputy Director and Head of Science at the Oxford Botanic Garden and Arboretum. Founded in 1621, it is one of the oldest science gardens in the world and a leading centre of research. Chris tweets regularly at @thorogoodchris1