Peacocks use their brilliant plume to woo peahens. The very same feathers render the male bird vulnerable to predators. How then did peacocks defy evolutionary adaptation to develop such strikingly colourful feathers? A new research that decoded the genome of India’s national bird may have answers.
Sequencing the genome of Indian peacock and comparing it with genomes of chicken, turkey, duck, flycatcher and zebra finch, Indian scientists have discovered a host of genes that play vital roles in feather patterning, bone and skeletal muscle development1.
They found that during the process of evolution, peacock diverged from chicken more than 25 million years ago. Genetically speaking though, peacock is closer to chicken than to turkey, the team led by Vineet K. Sharma, from the Indian Institute of Science Education and Research in Bhopal, has found.
Since they parted company with chicken, peacocks faced two events that drastically reduced the size of their population (called population bottlenecks) with selection of different genes. These genes have roles in cellular processes and early development pathways that regulate key features such as feather development, metabolism and immune response.
A set of 99 genes with multiple signs of adaptation was found in peacock genome. Many of these genes orchestrate signaling pathways that regulate initial placement of feather buds and their consolidation with the feather field. The genes involved in bone and skeletal muscle development perhaps shape the growth of peacocks’ large body with stronger legs and spurs, enabling this bird to take short flights despite its long train.
The study will also help devise better conservation strategies for managing Indian peacocks, which face habitat loss, poaching, and harmful effects of chemical fertilizers, says Sharma.