Red junglefowl are the wild ancestors of the chicken, and the two are understood to readily admix. In their native range in Southeast Asia, free-roaming red junglefowl display domestic characteristics a sign of domestic introgression into the wild population (shown here).
Quotes show that wild birds acquired 20% to 50% of their genomes from chickens.
According to a new study released in the journal PLOS Genetics, the red junglefowl, the wild forefather of the chicken, is experiencing a loss of genetic variety due to interbreeding with domesticated birds. The research study was led by Frank Rheindt of the National University of Singapore.
At some point in between 3,000 and 10,000 years ago, humans domesticated the red junglefowl in tropical Asia. Despite this, domestic and wild birds can still interbreed. This interbreeding in between domestic and wild red junglefowl is a cause for concern in terms of conservation, as wild populations that get more DNA from chickens might experience a loss of genetic diversity, making them more susceptible to modifications in their environment.
In the new research study, researchers contrasted entire genomes from 51 chickens and 63 junglefowl from across the wild birds natural range, to find signs of interbreeding. They saw that DNA from domesticated chickens is moving into wild junglefowl, and the scale of that motion has actually increased over recent years. By comparing modern-day wild genomes to genomes of red junglefowl from approximately a century back, the scientists approximate that the wild birds have inherited 20% to 50% of their genomes from domestic birds, depending upon their location. The study also identified eight genes that varied significantly between domestic chickens and their wild ancestors, and which were likely key to establishing the chicken as an animals animal. These genes are included in vision, reproduction, and advancement.
The results of the study expose the ongoing loss of hereditary variety in the wild junglefowl, and the researchers recommend that efforts may be needed to safeguard its genome. Additionally, wild populations have worth for farming because they can act as a tank of hereditary variety that researchers can tap into to enhance domesticated types– for instance, finding genetic variants that make an animal more resistant to a particular illness. Losing that hereditary diversity in red junglefowl may impede researchers capability to protect one of mankinds most essential food sources.
The authors include: “Genomes of 100-year-old birds show that modern-day wild junglefowl continues average more domestic DNA than they used to. The wild genotype is a crucial tank of chickens genetic variety and protecting it is crucial.”
Reference: “Historic samples expose loss of wild genotype through domestic chicken introgression throughout the Anthropocene” by Meng Yue Wu, Giovanni Forcina, Gabriel Weijie Low, Keren R. Sadanandan, Chyi Yin Gwee, Hein van Grouw, Shaoyuan Wu, Scott V. Edwards, Maude W. Baldwin and Frank E. Rheindt, 19 January 2023, PLOS Genetics.DOI: 10.1371/ journal.pgen.1010551.
Red junglefowl are the wild forefathers of the chicken, and the two are known to readily admix. In their research study, Wu et al. found evidence of a loss in wild genotype in the red junglefowl throughout the Anthropocene by comparing contemporary genomes with historical ones from around a century back. In their native range in Southeast Asia, free-roaming red junglefowl display domestic characteristics indicative of domestic introgression into the wild population (shown here). By comparing modern-day wild genomes to genomes of red junglefowl from around a century earlier, the scientists approximate that the wild birds have actually inherited 20% to 50% of their genomes from domestic birds, depending on their area.
