So let’s take a step back to find out a little about these valuable birds. Around 5,000 years ago in Asia, the red jungle fowl gradually gave rise to the modern chicken, which is now one of the most common and widespread domestic animals in the world. Estimates suggest that the worldwide chicken population is well over 24 billion (although I have no idea who counts them all!). That means there are more chickens in the world than any other species of bird. More than 50 billion chickens are reared annually as a source of food, and we eat both their meat and their eggs. In the UK alone, we eat more than 29 million eggs every day, so it’s a good thing that some breeds of hen can produce over 300 eggs per year, the record being a fairly staggering 371.