Bivalves

So what might be the ancestor of the bivalves - would it have most likely used a gill for one or the other of those functions?

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... within Ecology" was beaten into our heads in school. Think about corals competing for light and space on the reef with sponges, soft corals, bivalves and algae. Different kingdoms, phylums and orders all occupying and competing in the same space for the same or similar resources.

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... Class: Echinoidea Sea Urchins, Heart Urchins and Sand Dollars Class: Holothuroidea Sea Cucumbers Phylum: Mollusca Molluscs Class: Bivalvia Bivalves Class: Cephalopoda Squids, Cuttlefishes, Octopus, Nautilus Class: Gastropoda Snails, Slugs Class: Polyplacophora Chitons Kingdon: Plantae Phylum: ...

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... big marine molluscs or echinoderms, they will also watch those keenly. But, they will never take a glance at any small molluscs like snails or bivalves. Neither will they be interested in indigenous species of birds or snakes. Contrary to them, the city (obviously Indian) folks show more interest ...

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... that the other doesn't and this characteristic developed after the two diverged from their common ancestor. In the case of mollusca, bivalves (clams) are considered to be more advanced than the highly intelligent cephalopods (including squid and octopods) because of their more recently ...

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