What animals lay really big eggs?

The biggest eggs in the animal kingdom are laid by ostriches. Ostrich eggs can weigh as much as 3.5 pounds (1.6 kilograms). They are also the largest single cells in the world. Ostrich eggs are white and have a hard shell. They are laid in a nest on the ground. The female ostrich will sit on the eggs to keep them warm until they hatch. Ostrich eggs take about 45 days to hatch.