In the evolution of land-dwelling animals, several different phyla have made the transition from a strictly aquatic to a terrestrial (land-based) existence. Which of these phyla has remained exclusively an aquatic phylum?

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    Chordata
    Porifera
    Mollusca
    Arthropoda
asked May 19, 2013 in Biology by anonymous
    

1 Answer

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Porifera
answered May 20, 2013 by Bioshare ~Top Expert~ (34,070 points)



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