I Want One of These

The ice fish has no red blood pigments or red blood cells. This adaptation to the frigid environment allows it to use less energy to pump blood through its body.

OK, someone help a poor non-scientist with no biology since high school here: I thought the red coloration of blood was due to the oxidation of iron. How would the fish lose 'red blood pigments or red blood cells' and still respire?

I wondered that too. Unfortunately, I haven't the slightest idea. I just want one for my aquarium. I wonder if you can get a machine that pressurizes the aquarium and keeps it at like 35 degrees F?

I wondered that too. Unfortunately, I haven't the slightest idea. I just want one for my aquarium. I wonder if you can get a machine that pressurizes the aquarium and keeps it at like 35 degrees F?

I read an article on this a while ago. They basically use their own unique circulatory system. It breaks down if the water gets too hot. It was in a global warming article in Skeptic, or Skeptical Inquirer, or something.

The soluability of oxygen in water goes up as temperature goes down. At near-freezing temperatures, there is enough oxigen dissolved in the water for the fish to use sea water, with a bit of "anti-freeze" (no, I don't know what it is) to get the job done without hemoglobin.

At near-freezing temperatures

On the other side of "freezing" -- seawater doesn't freeze above something like -2 °C. In any case the water in question is reported to have -1.8 °C.

a bit of "anti-freeze" (no, I don't know what it is)

A little protein that mops up microscopic ice crystals, prevents them from growing, and allows the fish to excrete it over the gills or something.

Incidentally, the gene for the antifreeze protein evolved from junk DNA. That's right, a start codon and a stop codon must have appeared in a stretch of random sequence.

The ice fish has no red blood pigments or red blood cells. This adaptation to the frigid environment allows it to use less energy to pump blood through its body.

Recalling (and reading...) this years evolutionary bio notes, that's disputable. There's a range of adaptions the fish need to overcome the loss of haemoglobin, such as no scales and rather large energy budgets for the heart, on par with mammals.

And to answer Chuck C's question, oxygen can still dissolve on the blood, but it should be at the same concentration as the surrounding water, so to get to the tissues the ice fish pump more blood around and respire through their skin.

Incidentally, the gene for the antifreeze protein evolved from junk DNA. That's right, a start codon and a stop codon must have appeared in a stretch of random sequence.

Yes and no, the anti-freeze gene is related to a digestive tract protease, referring to notes, it's related to trypsinogen-like serine protease that underwent expansion with Thr-Ala-Ala repeat units in the middle of the gene.

There's even an example (iirc) that still have protease activity, from teh notes;
"Possibly the most exciting finding has been the discovery of an evolutionary intermediate, transcriptionally active chimaeric gene that encode both an AFGP polyprotein and the protease in D. mawsoni."

looks like a dragon alligator fish to me

It looks so cute!!!!!!

Im doing my history project on the Ice Fish

I WONDER HOW THESE FISH MAY BE ALIFE AT TEMP BELOW 0 DEGREE. IT WOULD BE INTERESTING TO HAVE MORE DETAILS ABOUT THE SAME.