Also known as Eggs and Bacon, the Common Toadflax grows in scrubby ground, under hedgerows and in verges, showing spikes of yellow and orange flowers. It is pollinated by insects, whose reward is a sugary nectar, held at the base of a specialised structure called a ‘nectar spur’ – a long, tapering tube. The length of the spur restricts nectar collection to pollinators with tongues of particular lengths. It is thought to be a ‘key innovation’ in flowering plants that can lead to rapid speciation, through reproductive isolation due to pollinator specificity.
Given that there are no model plant species which possess a nectar spur, researchers in the Department of Plant Sciences are comparing the well-known study system Antirrhinum majus (snapdragon), which possesses only a nectar pouch, called a gibba, with the Common Toadflax (Linaria vulgaris), a related species within the Antirrhineae which possesses a spur, to study nectar spur development.