Why is cassowary eggs green?

Cassowary eggs are green due to the presence of pigments in the eggshell, primarily biliverdin, which is a breakdown product of hemoglobin. This green coloration helps provide camouflage in the dense forest floor of their natural habitat, protecting the eggs from potential predators. Additionally, the unique coloration may also play a role in regulating temperature and protecting the eggs from harmful UV rays.