In a painting of Jehangir’s turkey, a glimpse of the complex history of food.

The emperor Jehangir was fascinated by a turkey. In his memoir Tuzk-e-Jahangiri, he wrote: “Its head and neck and the part under the throat are every minute of a different colour. When it is in heat it is quite red – one might say it had adorned itself with coral – and after a while it becomes white in the same places, and looks like cotton.”

This is standard behaviour for a male Meleagris gallopavo, the North American turkey. The skin on its head can switch between blushing red, mottled blue and livid white because of collagen fibres interspersed with blood cells that lie just beneath the skin. As the blood vessels contract or expand according to the male turkey’s mood, they alter how light reflects off the skin, causing the colour to change.