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Sunday, May 11, 2014


GOZRadio, GOZRadio Live, GOZRadio Listen Online, Christian Contemporary Radio, USA

And it has one further attribute, which Aysheaia could not have had. It has tiny little holes all along its flanks, which enable it to breathe air. So this is one of the first creatures that moved on to land, million years ago. Velvet worms may have been the first Online Radio to set foot on land, but they have hardly changed during the following halfbillion years. Why? Well, unlike true arthropods, their bodies are covered, not by an exoskeleton, but by soft, permeable skin. That lack of an external skeleton means that their bodies, unsupported by water, can't grow any bigger. It also means that in order to prevent themselves from drying out, they have to stay in damp environments. True arthropods, like this scorpion, a descendent of those giant sea scorpions, were not so restricted. They had external skeletons. That meant that not only were their bodies protected from drying out, but they were strong and rigid enough to allow them to grow bigger and get around without the support of water. So how and when did true arthropods with exoskeletons draw their first breath of air? The answer can be found in this. It is perhaps the smallest and most fragmentary fossil I've seen so far, but don't be fooled by appearances. It's almost certainly one of the most significant. This specimen was collected in Cowie Harbour, here in Scotland, in . Even though it's so small, under the microscope you can see extraordinary detail. This is the main body of the animal with its segments. And here are its legs. But above each there is a tiny hole. That is a spiracle, through which the animal was able to breathe air just as insects do today. And since it breathed air, if it had gone into the water it would have drowned. So this is a truly landliving animal and what is more, it's the first and oldest that we know. It's million years old. But what kind of creatures were these early landdwelling arthropods Online Radio very like them are still quite common in many parts of the world. There are certainly plenty of them in those Australian rainforests.

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