When my nephew was an infant he paid a visit to the doctor because my sister was worried he was showing signs of jaundice. His yellowish hue, it ends up, was the result of a diet that consisted primarily of sweet potatoes, carrots and squash.
Flamingos are pink for the exact same reason. It has to do with what they eat. This cartoonish looking creature can range in colour from pale pink to vivid orange-red. Their unique diet, consisting of algae and small animals such as insect larvae, mollusks and shrimp, is where it all begins. The beta carotene in these foods, once digested, turn to pink or orange. The more a diet is dominated by the distinct pigments of the carotenoids, the richer this wading bird’s colour will be. Flamingos start out life covered in a light grey plumage and become more colourful as they mature. Whereas, we humans age the other way around.