Some segmented marine worms possess pink blood.
The Secret of Pink Blood
The unique pink hue of the blood in certain marine worms is due to hemerythrin, a distinct type of blood pigment responsible for oxygen transport. Unlike the iron-based hemoglobin that gives most animals red blood, hemerythrin contains iron, but its chemical structure and binding with oxygen results in a pink or purple coloration.
Several sources confirm this fact. For example, The Conversation explicitly states that "One group of segmented marine worms has pink blood." This is further corroborated by other research indicating that the oxygen-carrying molecule hemerythrin is responsible for the pink or purple color. It's important to note that not all worms, nor all marine animals, have pink blood; this characteristic is specific to a particular group of segmented marine worms.
While some sources may suggest otherwise, this is the confirmed scientific finding. The assertion that "There aren't any animals with pink blood" from Quora is not entirely accurate.
