Bumblebees can identify different flowers by the invisible patterns of scent across their surface, new research has found.
The work, led by scientists from the University of Bristol and Queen Mary University of London, has revealed how bees learn the patterns and distinguish between flowers.
Flowers have different patterns of scent across their surface, with visiting bees finding that the edge of the petals may smell different to the centre.
This is in addition to patterns on flowers - such as lines pointing to the centre - that help guide bees and other pollinators towards the nectar.
Research published in the journal Proceedings of the Royal Society B shows how bumblebees can tell flowers apart by how scent is arranged on their surface.
"If you look at a flower with a microscope, you can often see that the cells that produce the flower's scent are arranged in patterns," says Dr Dave Lawson, from the University of Bristol's School of Biological Sciences.
The study found that once bees learnt a pattern of how scent was arranged on a flower, they preferred to visit unscented flowers with a similar arrangement of visual spots on their surface.
Dr Lawson described this as being the equivalent of a human putting their hand into a bag to feel the shape of an object and then picking out a picture of it.
"Being able to mentally switch between different senses is something we take for granted, but it's exciting that a small animal like a bee is also able to do something this abstract," he said.
Dr Sean Rands, also from Bristol, added that flowers "advertise" to their pollinators by using a mixture of colour, shape, texture and smell.
The study is part of ongoing research at the University of Bristol into different ways that flowers communicate with their pollinators.
