Horseshoe crabs are primitive animals, and I found out yesterday that they have blue blood. That was going to be my post. Look at the cool blue color:As you can see -- milky blue. The blue color is caused by the hemocyanin in their blood, rather than hemoglobin. Hemocyanin is based on copper rather than iron. It is not uncommon undersea non-vertebrates, being in mollusks and octopus too. There is lots of detail on Wikipedia.
However, it is even more interesting that horseshoe crab blood has an unusual anti-bacterial property.
Horseshoe crab blood, as discovered by Fred Band in 1956, contains Limulus Amebocyte Lysate a which causes clots in response to lipopolysacchrides of the kind found in bacteria. The clotting occurs quickly and isolates the bacteria from the rest of the crab. It is useful pharmaceutically to detect bacterial contamination. This can detect roughly 10E6 organisms/ml, depending on the organism and many other factors. Actually this does not sound that sensitive to me, but it seems that other methods are worse.
Recently, this has created a market in wild horseshoe crab blood. The crabs are milked and then released. It seems that it is difficult to culture the cells that produce limulus amebocyte lysate in the lab, and that the wild-caught production will continue for a while.
You say nothing about how SAD THIS IS.
ReplyDeleteThis is vampire-like. I mean drinking blood is worse than say catching shrimp and eating them.
ReplyDeleteOn the other hand, most of the horseshoe crabs live to see another day, and that is good. If the crabs were getting killed needlessly, than that would be more sad.
Didnt mom say something about how a large percentage of them die? Look at the poor thing sitting on the shelf like that. This is ridiculous. I know it is a primitive animal, but it just seems wrong somehow.
ReplyDeleteHa, this sort of leads to this question about people: which is better, slavery or cannibalism?