Regarding Are flamingos pink because they eat shrimps? and perhaps If blood is red then why do your veins look blue?…
Someone in a closed thread mentioned that horseshoe crabs have blue blood. I had heard somewhere that this is because their version of “hemoglobin” is based on copper, and that by the same token plants’ chlorophyll is “the same” molecule, based on magnesium. From elsewhere I gather that this is not true, but in fact that there are lots of different colors of blood among various species, and in fact that the difference hinges on the metal in their blood pigments (which may or may not carry oxygen). Among them:
[ul]
[li]Red–iron–mammals, etc.[/li][li]Green–magnesium–plants (chlorophyll)[/li][li]Also Green–vanadium–sea squirts[/li][li]Also Green–(iron? large hemoglobin assemblages)–bristleworms[/li][li]Purple–“binuclear” iron–penis worms[/li][li]Blue–copper–octo- and arthropods[/li][li]Clear/grey–no oxygen-binding pigment–certain fish[/li][/ul]
I got this from Hemoglobin And It’s Substitutes. Obviously this is a very simple presentation of something vastly complex. Does it carry a grain of truth?
Just curious. One hears things and wonders.
