The Modern fauna - the great carnivore crisis 1. Sepkoski’s Curves 2. The Modern fauna 3. Bivalves 4. Ammonites 5. G

1. The Modern fauna - the great carnivore crisis 1.Sepkoski’s Curves 2. The Modern fauna 3. Bivalves 4. Ammonites 5. Gastropods 6. Echinoids 7. Ecological overview

2. 1. Sepkoski’s Curves Family diversity Modern fauna End Permian extinction Ordovician radiation

3. 2. Modern fauna Many active predators Simple brachiopods Intense burrowing below sea floor

4. 3. Bivalves Bivalves are molluscs with two shells. Most filter feed and live infaunally. Shell Mantle, with inhalent and exhalent siphons Foot Burrowing adopted as lifestyle in Jurassic.

5. 4. Ammonites Swimming, predatory molluscs with a coiled, external shell. True ammonites had complicated sutures between segments of their shell and are only found in the Mesozoic.

6. 5. Gastropods Predatory, grazing or scavenging molluscs Inhalent siphon – mantle extension used to direct water to gills (within mantle cavity) Mouth, with rasping radula Foot – flattened muscular foot used for locomotion

7. 6. Echinoids Echinoderms with internal, calcareous skeleton comprised of multiple plates. Begin to burrow in Jurassic Madreporite – highly perforated plate through which seawater is bought into water vascular system. Aristole’s Lantern –movable skeletal plates that act like jaws.

8. 7. Ecological overview 1. Modern fauna is most diverse marine community of Phanerozoic. 2. Diversity rises to around 600 families 3. A wide range of primary consumers 4. Tiered above and below seabed 5. Highly diverse array of predators 6. Recovered best from end Permian extinction, perturbed but not fundamentally affected by end Cretaceous event.