Eggs are nature’s complete package. They carry a growing baby while providing it with nutrients and sheltering it from the outside world. Many animals lay eggs as a way to reproduce, but we will focus on birds in this lesson. Bird eggs must be incubated, or kept warm, by the mother or father bird. Other than that, they come equipped with everything they need. Bird eggs all serve the same function even though appearance may vary between species. Color, size, shape and even texture can all be different. For example, a robin’s egg is similar in shape to a chicken egg, but it’s quite small and light blue in color. A great horned owl egg, on the other hand, is larger, nearly round, and whitish in color.