This is the story of one of the most important animals in modern history. Chickens, the world’s chicken population is over twenty three billion. Making them the most numerous species of bird on the planet. Over sixty billion are slaughtered for food every year. Compared to one point five billion pigs. And three hundred million cattle. Chicken meat consumption is increasing faster than any other meat. Driven by exploding demand in developing countries. But the chickens we know today are not what they used to be. They originated from the red jungle fowl, native to South and South-East Asia. Over millennia, humans have brought them to all corners of the global. And, in doing so, they have changed what it means to be a chicken. Modern chickens are twice the size they were in the late medieval period. And since 1950, their growth has accelerated; they are now five times the mass than they were in the 1950s. They are growing so quickly that by the time they are five-six weeks old, they are ready for slaughter. Chickens are so ubiquitous.
While humans have been selectively breeding chickens since their domestication in South-East Asia around six thousand years ago, the speed and scale of change in the twentieth century is far beyond anything observed in the past. From the 1950, the chicken population has risen in step with the rise in human population, as has our use of fossil fuels, plastics and other resources. Now, this animal is more numerous than any bird species in Earth history.