The journey of a bird egg starts with a tiny ova, which grows into an egg yolk. When ready, the yolk is released along the oviduct. The egg white is first to be added at the start of the oviduct, which consists mainly of protein, water, and minerals. As the egg carries on along the oviduct, it grows two connecting strands, one at the top and one at the bottom. Which helps anchor the yolk to the shell and keeps it in the center of the egg. After this, the egg continues down into the uterus, where the shell is added. Which is made from calcium carbonate. In order for air and moisture to pass through the pores, it’s made up of a semipermeable membrane.
Two pigments, one greenish in colour and the other is reddish-brown. When used in different combinations with the white calcium carbonate of the shell, they can provide egg colours from greenish-white to rich brown and deep blue. And speaking of deep blue. A study was conducted to see how a male robin would react if its mate laid eggs that were a brighter shade of blue. The idea was to test if brighter egg colour was a signal of the quality and health of their mate, and in turn, the healthy mate would create healthier babies. In conclusion, the males whose nest contained the brightest blue eggs, fed their young twice as much. Thus resulting in healthier young.
Biliverdin is the pigment that is responsible for the American Robin egg colour. It is possible that higher biliverdin levels in female robins indicate a healthier female capable of producing healthier young.
Now the next experiment should be, is eating brighter blue eggs healthier for you?
