The 
Parazoa are an ancestral subkingdom of the 
animals, literally translated as 'beside the animals.'  Parazoans differ from their 
choanoflagellate ancestors in that they are macroscopic and have 
differentiated cells, but unlike "true animals" (
Metazoa), they do not have 
tissues.  The only surviving parazoans are the 
sponges.
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