Blue Blooded Horseshoe Crabs

On our second trip to the Florida Keys Aquarium Encounter, this time with our granddaughter, I picked up another little tidbit of knowledge I hadn't had before. The touch tide pool was her favorite spot and one of the older attendants whom we'd met before was very patient in explaining to her and to others as they came along and wanted to touch what each animal was and what their importance was in the world.

Our granddaughter was especially fascinated with the horseshoe crabs in the pool. When you turned them upside down, remembering to keep them under the water of course, you could see all the legs scrambling to move. They are a unique sea animal with their armored outside that to me looks like it's related to an armadillo even though it's really related to the group that includes spiders.

While the long needle like tail looks dangerous it is only used to right itself if it is accidentally turned over. The shell-like armored body has been around for over 450 million years as evidenced by fossils. Apparently God didn't need to improve on this particular animal.

Horseshoe crabs are important to the ecology of the region because of their eggs. The eggs provide a food source for both birds and fish. Amazing that any would survive.

The truly surprising fact I learned however was that they have blue blood. This is because it is copper-based. It is used to test for the sterility of medical equipment and all intravenous drugs. The compound eye of the horseshoe crab has also been important in learning more about vision in the human eye.

Okay, now I'm ready for the Jeopardy show.