Most people call them crabs, but they are more close to spiders and scorpions. Actually, they are like the big grand father of all this kind. A living fossil, who saw when its lost brothers: the Trilobites and the Marine Scorpions, ruled the world.

Nowadays they can be find in the indopacific and the atlantic coasts of north america, and they atonish the scientists, not only for being a sursivor from the past, but also for their curious behavior, and some incredible properties.

Its reproductive behavior, for example, is guided by the moon cicle. Its ten composed eyes, spread around its body, can detect the ultraviolet moonlights. So the crab can know when the full moon and the new moon are coming and arrive to the mating places in time to seek for a couple.

But the most important of these creatures are the properties of theyr blood. Theyr blood is not composed by iron like human blood, but by copper. This and some especial chimics give an amazing blue tone to the liquid, and the most important, it gives the crabs blood the power to detect the presence of bacterian toxines in its body, and, as answer, to clot extremelly quick, before more bacteria could enter. This property is used in laboratories worldwide to prove if medicines and medical instruments are really sterile and able to be used in people.

So, who knows? Maybe this unknown animal has saved your live many times.

Version en espanol (spanish version)