Surprised there is no mention of lobsters, who, like crocodile icefish have colorless blood. For lobsters it appears blue once it comes in contact with oxygen [0].<p>0: <a href="https://www.fisheries.noaa.gov/national/outreach-and-education/fun-facts-about-luscious-lobsters" rel="nofollow noreferrer">https://www.fisheries.noaa.gov/national/outreach-and-educati...</a>
Along a similar line, look into animals that don't sweat clear! Hippos sweat red, so they look like they're just covered in blood sometimes. Horses sweat white, so they look like they're just... well, you can go see for yourself.
I'm surprised hemocyanin isn't poisonous to us, or at least bad. Ingesting copper just doesn't sound healthy. AFAIC it isn't something we usually do either, so no pressure to evolve a way to metabolise it either.
This website manages to both hijack the back button and not show a single picture of any of the blood that the entire article is about. Fuck this website.
Minor yet important typo.<p>"Crocodile icefish frequent brutally cold portions of the sea where the water temperature can plummet all the way down to 28.5 degrees Fahrenheit (1.9 degrees Celsius). That's below the point at which fresh water freezes."<p>28.5F is minus -1.94C