As you may know, evolution contains many complexities and mysteries that we have been unraveling since Charles Darwin published “On the Origin of Species” in 1859. Still There are so many wonderful discoveries to be found when we look at our world, especially when it comes to birds. If you have ever encountered a bird’s nest in the wild, you will know that the eggs come in many colors and are extremely diverse in appearance. They often have spots, and sometimes eye-catching colors. However, one of the most curious types of bird eggs are those that are blue in color.

Many common bird species around the world have been observed laying blue eggs in the wild. For example, blue jays, robins, bluebirds, starlings, house sparrows, thrushes, red-winged blackbirds and magpies have all been documented to lay blue eggs (according to The Spruce).

Understanding the process by which birds create blue eggs is necessary before trying to understand why they do so. Unlike mammals, birds do not have a uterus; Instead, they use a structure called the cloaca – a cloaca to deposit their eggs (according to The Spruce). Cloaca serves as a digestive and reproductive site. In addition, the chemical pigment biliverdin found in the nectar of some birds also appears during the process of building the shells of their young (according to Optics Mag). This compound is responsible for the appearance of blue in the eggs of some birds.

Many bird species are known to lay multiple eggs per nest build (according to All About Birds). Higher concentrations of biliverdin cause the first eggs to be darker in color, while subsequent eggs may be lighter in color. We now understand why some birds have blue eggs, but why are blue eggs beneficial to certain birds?

Bright blue bird eggs easily stand out in the nest. As a result, any potential predator can easily see them as lunch! Therefore, the idea that blue eggs provide protective camouflage in the nest is not as clear as it is for other birds that lay brown eggs, such as quail. This dominant idea associated with the color blue tends to indicate eggs and the important role sunlight plays in their development. Birds often lay colored eggs that correspond to their environment. Unhatched chicks are very sensitive to the sun’s heat and radiation, which can cause developmental delays or even death (according to Optics Mag).

White or light-colored eggs are more commonly found in nests in warmer, more light-filled areas, and as a result, they more easily absorb the Sun’s ultraviolet radiation (according to the World Animal Organization ). However, darker eggs will appear in nests that are cooler under light, as too much radiation can be dangerous during incubation. As a result, blue eggs are in an evolutionary sweet spot (according to Forbes ), essentially benefiting from the sun’s rays, but not to the point of harming them.