Chickens Outnumber Humans 3 to 1

With the global human population at about 8 billion, there are roughly 25 billion chickens alive at any given time, meaning chickens outnumber humans by more than 3 to 1. This makes chickens the most numerous bird species on Earth by far. The vast majority of these chickens are raised for food production. China has the largest chicken population, followed by the United States and Indonesia. Chickens are so numerous that their bones are becoming a defining feature of the geological record, leading some scientists to suggest they're a marker of the Anthropocene epoch.