Canadaspis is an early representative of crabs, lobsters and shrimps. It is the second most common to be found in the Burgess shale and can be up to 7.5cms in length. The structure of the limbs indicated they were used primarily for walking. The limbs allowed the animal to scrape and dig sediment in search of food .Outer flap-like limbs provide a mechanism for swimming by moving downwards in a wave like motion along the thorax. These flaps were used in respiration by exchanging oxygen with the surroundings.
Pencil and carbon dust on paper
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