Boto

Boto is a Portuguese name given to several types of dolphins and river dolphins native to the Amazon and the Orinoco River tributaries. Some botos exist exclusively in fresh water. The Boto dolphin is usually pink in color and tends to become more pink in age. The degree of pinkness would be a sign of maturity in males and could therefore have the same display function as antlers in red deer or the tusk in narwhals. They become more pink in age because of scar tissue that takes over their whole body. They also lose some of their pigment throughout their adolescence, turning them light pink.

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