Short answers, pulled from the story.
Genomic studies estimate that chicken domestication occurred around 8,000 years ago in Southeast Asia. This revised the previously accepted date of roughly 5,400 years ago. A 2020 Nature study sequencing 863 chickens worldwide traced all domestic chickens to a single domestication event involving red junglefowl whose present-day range is centered on southwestern China, northern Thailand, and Myanmar.
Pork is the most widely eaten meat globally, accounting for about 38% of total meat production. Poultry is second at about 30%. Together, pork and poultry made up over 70% of the global meat supply in 2012.
The turkey was first domesticated by pre-Aztec tribes in south-central Mexico around 800 BC. Pueblo Indians on the Colorado Plateau in the United States also domesticated the bird around 200 BC, initially using the feathers for robes, blankets, and ceremonial purposes rather than as food.
Battery cages for laying hens were banned across the European Union as of the 1st of January 2012 on animal welfare grounds. The cages confined several birds to a small shared space, restricting their ability to move or exhibit normal behaviour.
Millions of fertilized chicken eggs are used each year to grow the annual influenza vaccine. The process takes about six months from the decision on which virus strains to include to the finished vaccine. People with egg allergies cannot receive egg-based vaccines, but cell-based culture methods are being developed as an alternative.
Dark meat comes from muscles used for sustained activity, and its colour is caused by the protein myoglobin, which manages oxygen storage and uptake in muscle cells. Ducks use their breast muscles for sustained flight, so those muscles are red throughout. Chickens' breast muscles are built only for short bursts of activity, so the meat is white.