Why did the pigeon stand sleeping

It is normal for pigeons to sleep.The pigeons have a strong balance. When sleeping, they will be on the ground, and the other feet will shrink into the feathers, and their heads will be buried in their wings.This sleeping position can be kept vigilant and ensure that the pigeons can escape at any time when they encounter danger.The way of sleeping in the pigeon determines that it must have its own habitat or nest box, while the lord's environment should be quiet and dim.Pay attention to windproof in winter, pay attention to heatstroke prevention and mosquitoes in summer.