The domestic chicken could become the defining symbol of the current geological age, says The Guardian. Many scientists are calling the present era the “Anthropocene,” because it is marked by human impact on earth. And that includes the chickens we have kept and slaughtered ever since villagers in southeast Asia first captured its slow-flying ancestor, the red junglefowl, 7,000-10,000 years ago.
“[The domestic chicken] has become the world’s most common bird. It has been fossilized in thousands of landfill sites and on street corners around the world,” says Professor Jan Zalasiewicz, a geologist at the University of Leicester and the chair of the Working Group on the Anthropocene.
Almost 60 billion chickens are slaughtered each year, with 75 percent of that meat coming from industrial farms. For most of history, chickens were used almost entirely for eggs, since it was too inefficient to raise them for meat. But after World War II, poultry operations industrialized, integrating hatcheries, grain supplies and slaughterhouses into massive battery farms, says The Guardian. Vaccines and antibiotics helped the chickens survive intense confinement, speeding their rate of growth from 18 weeks in the 1950s to 6 weeks today. At least half of ancestral chicken breeds have disappeared, however, giving way to the few varieties preferred by industry.
The UN Food and Agriculture Organization predicts that chicken will be the most world’s popular meat by 2020, surpassing pork. But in order to become the official symbol of the Anthropocene, domestic chickens will have to beat out nuclear bombs, concrete and plastic pollution.