For centuries, the question of which came first – the chicken or the egg – has been a source of amusement and philosophical debate. However, a recent study published in Nature Communications sheds new light on the origins of chickens and pinpoints a crucial factor in their global success: their ability to lay eggs year-round.
Previously, understanding the history of chicken domestication was hampered by limitations in identifying chicken bones from their wild ancestors. New archaeological techniques, however, are changing the game. This international research team, comprised of archaeologists, historians, and biomolecular scientists, has presented compelling evidence for the earliest instance of raising chickens specifically for egg production.
The study hinges on the analysis of eggshell fragments collected from 12 archaeological sites across Central Asia, spanning a period of roughly 1,500 years (400 BCE to 1000 CE). These sites lie along the ancient Silk Road, a major trade route that facilitated cultural and biological exchange across Eurasia and North Africa.
The sheer abundance of eggshells unearthed offers a key clue. Unlike their wild ancestors, the red jungle fowl, which lay just a handful of eggs per year, these domesticated chickens were prolific egg-layers. This discovery was made possible by ZooMS, a biomolecular analysis technique that identifies the source of animal remains based on protein signatures. It offers a faster and more cost-effective alternative to traditional DNA analysis.
“This study showcases the potential of ZooMS to shed light on human-animal interactions in the past,” explains Dr. Carli Peters, lead author of the paper and researcher at the Max Planck Institute of Geoanthropology.
The researchers believe this ability to lay eggs outside their natural breeding season is the driving force behind the widespread adoption of chickens. This characteristic made them a highly valuable commodity for ancient populations, contributing significantly to their dispersal throughout Eurasia and North Africa.
“This is the earliest evidence for the loss of seasonal egg laying yet identified in the archaeological record,” says Dr. Robert Spengler, who led the research team. “It’s an important piece of the puzzle for understanding the symbiotic relationship between humans and animals that ultimately led to domestication.”
This groundbreaking study not only offers a compelling answer to the age-old chicken-and-egg dilemma but also highlights the power of interdisciplinary collaboration and innovative techniques in unlocking the secrets of the past. By focusing on the ability to lay eggs year-round, the research suggests that this seemingly simple trait played a pivotal role in transforming the chicken from a wild jungle fowl into the global economic powerhouse it is today. As the authors point out, this study paves the way for further exploration of long-standing historical questions using cost-effective and interdisciplinary approaches.
Source: Max Planck Society