5. major “invertebrate” phyla a. porifera: sponges b. cnidaria: corals, hydra, anemones,...
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5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfish
Protostomes - Lophotrochozoans
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfish
Protostomes - Lophotrochozoans
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatworms
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatworms
Cephalization: eyespots and auricles
Gastrovascular cavity convoluted gut Ameobocytes
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatworms
Parasitic forms: Flukes
Asexual reproduction – population increase!
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatworms
Parasitic forms: Tapeworm
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented worms
Polychaete worms
Oligochaete (‘earth’) worms
Leeches
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented worms
Body cavity (coelom)
Hydrostatic ‘skeleton’
Complete gut (‘tract’)
Cephalization
Segmentation
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
Earliest mollusc, from the Burgess shale, dating to 560 mya, just before the Cambrian Radiation. It is a soft-bodied mollusc
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
The ancestral state is segmentation as in the chitons. In the rest of the group there is reduction of sementation.
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
The ancestral state is segmentation, as in the chitons. In the rest of the group there is reduction of segmentation.
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
The pretty nudibranchs!!
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
In sessile bivalves, there has been ‘decephalization’ – loss of head
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
In sessile bivalves, there has been ‘decephalization’ – loss of head
Scallop eyes
5. Major “Invertebrate” Phyla
a. Porifera: Spongesb. Cnidaria: Corals, Hydra, Anemones, Jellyfishc. Platyhelminthes: Flatwormsd. Annelida: Segmented wormse. Mollusca: Chitons, snails, bivalves, cephalopods
In cephalopods, the shell is reduced from external to internal bony to internal cartilaginous to gone
Folded front to back
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