How long can eggs survive outside body?

Eggs can survive outside a bird's body for varying lengths of time depending on the species and environmental conditions. Generally, fertilized eggs can remain viable for several hours to a few days, while unfertilized eggs can last longer but may not develop into embryos. Factors such as temperature, humidity, and exposure to predators also significantly affect their survival. In optimal conditions, some eggs can remain viable for several weeks, but this is less common.