Flamingos are not born pink: chicks hatch a dull grey and only slowly take on their famous colour as they feed on algae and tiny brine shrimp loaded with pigments called carotenoids — which means a flamingo’s brilliant flush is essentially a visible read-out of how well, and how richly, it has been eating

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Flamingos are not born with their distinctive pink color. Instead, chicks hatch with dull grey or white down and remain that way for a while. The famous rosy color develops over time as they feed on certain foods.

Their diet of algae and tiny brine shrimp, which are loaded with carotenoids, determines the intensity of their color. The pigments from these foods cause the flamingos to take on their characteristic pink hue, making their color a reflection of their eating habits.