It was almost bound to be small and seemingly insignificant but the oldest species of earth is a shrimp, ironic given the connotations of its name in the English language. Rather than being the runt, the squirt and the general nobody its name implies, this little guy (the Horseshoe shrimp to friends butrather more formally) has staying power. It is almost the same now as it was two hundred million years ago.So, this little chap wasn’t just around when dinosaurs roamed the earth, it was around when they were evolving. Now researchers from the University of Glasgow in Scotland have discovered two hitherto undiscovered colonies of the rare shrimp. And they did so in quite an unusual manner.The shrimp has a certain trick up its sleeve. When the weather is dry the water pools in which they live dry up and the adults die. However, the eggs can survive in the sand even through periods of extreme dryness – and for up to twenty years.The researchers took mud that they suspected might contain shrimp eggs and placed it in to one of their aquaria. Sure enough a few weeks later (after water had been added) they discovered a shrimp. It is this ability which has seen the horseshoe shrimp occasionally marketed in a similar way to thein the US.One of life's great - if not greatest - survivors.