Why do flowers have colours? Do varying hues alter their properties?
Such questions prompted Nobel Prize-winning physicist C.V. Raman to focus his efforts on studying floral colours and their roles in attracting pollinators and shielding flowers from predators during his final years.
As the nation celebrated yet another National Science Day on Monday to commemorate the discovery of Raman effect, an eponymous laboratory in Kerala has been making strides in creating a comprehensive spectral library of flora in the country.
The research by Athira K., an assistant professor at the C.V. Raman Laboratory of Ecological Informatics in the Digital University Kerala, is spurred by a broad understanding of the importance of the colour of angiosperms (or flowering plants) in attracting pollinators. With the characteristic found to be extremely crucial in stabilising the declining population of wild pollinators, the study held immense relevance for policy makers in promoting crops.
The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services had in 2016 published a study that raised caution against the critical impacts that the declining pollinator population could have on the ecosystem.
Dr. Athira, who is guided by Prof. R. Jaishanker, chairperson of the School of Informatics at the university, says the country has focused on improving the production of food crops, while others such as the US, the UK and France have undertaken studies on the topic.
Through her floral radiometry study, the researcher has compared the floral spectral reflectance of 700-odd invasive and non-invasive species through expeditions made to several biodiversity hotspots on the Western Ghats including Ponmudi, Munnar, Banasura, Brahmagiri and Chembra.
The findings revealed varying flower colour perception among humans and bees. For instance, jasmine might appear white in colour, but they are green for the pollinators. Similarly, Mimosa Pudica, which is commonly known as ‘touch-me-not’, are also green flowers for pollinators and insects and not pink as seen by mankind. Bee pollinators have a floral colour preference towards ultraviolet (UV), UV blue, and blue flowers.
Dr. Athira hopes to travel far and wide to study more species among the nearly 4,500 angiosperms found in the country.