Across Laikipia, a few birds seem to shimmer more brightly than the rest, the Superb Starling, the Red-winged Starling, and Fischer’s Starling. All three display striking iridescent plumage, yet they produce these colours through distinct microscopic mechanisms involving uniquely shaped melanosomes, tiny, pigment-containing structures within feathers.
At Mpala Research Centre, Dr Frane Babarović investigates how these melanosomes form and change during feather development. Iridescent colours are structural, meaning they arise not from pigments but from the precise arrangement of cellular components that scatter and reflect light. The project focuses on two key traits, flatness and hollowness, which determine how melanosomes pack together and how light refracts to create shimmering colours.
Each starling species represents a different melanosome type:
🪶 Superb Starling – flat and hollow
🪶 Fischer’s Starling – round and hollow
🪶 Red-winged Starling – round and solid
By studying feathers at early growth stages, the project aims to uncover the anatomical features and genetic pathways that shape these melanosomes and, ultimately, the brilliant colours they produce.
The research involves capturing birds in the wild and temporarily housing them in aviaries at Mpala. Newly regrown feathers are collected at defined stages for both gene expression studies and microscopy, while additional feathers are analyzed with a spectrophotometer to measure their colours. The birds receive daily care and a consistent diet of ugali, minced meat, and papaya.
This project is led by Dr. Frane Babarović, a Marie Curie Postdoctoral Fellow affiliated with Ghent University and Columbia University, in collaboration with Professor Dustin Rubenstein’s team. They are especially grateful for the expertise of Wilson Nderitu, who has studied Superb Starlings for over two decades, and Kelvin, who ensures the birds’ welfare and protection from curious neighbours like baboons. Additionally, Rita Semeten has supported the project through sample organisation and preparation.
The fieldwork, especially capturing the birds, remains one of the greatest challenges, but also one of the most rewarding aspects of working to uncover the mechanisms behind nature’s iridescence.
Project lead: Frane Babarović, European Commision (Marie Curie Fellowship) shared between Ghent University in Belgium and Columbia University, US.