Shark Jaws and Teeth Lab

1. Shark Jaws and Teeth Lab • The shape of a shark's tooth depends on its diet; those that feed on mollusks and crustaceans have dense flattened teeth for crushing, those that feed on fish have needle-like teeth for gripping, and those that feed on larger prey such as mammals have pointed lower teeth for gripping and triangular upper teeth with serrated edges for cutting. The teeth of plankton-feeders such as the basking shark are greatly reduced and non-functional. • Shark teeth can be said to form rows both parallel and perpendicular to the line of the jaw. In taxonomy, shark teeth are counted as follows: rows of teeth are counted along the line of the jaw, while series of teeth are counted from the front of the jaw inward. Therefore, a single tooth row includes one or more functional teeth at the front of the jaw, and multiple replacement teeth behind. For example, the jaws of a bull shark can have 50 rows of teeth in 7 series, with the outermost series functional. The small teeth at the symphysis, where the two halves of the jaw meet, are usually counted separately from the main teeth on either side • For the following specimens: • Sketch the jaws & teeth from each • Describe (in a few sentences) for the form & function of the jaws and teeth explain their diet and feeding style

2. Shark Jaws and Teeth Lab • A) Great White Shark (Carcharodoncarcharias) • Diet: fish, pinnipeds, seabirds, cetaceans (whales & dolphins) • Tiger Shark (Galeocerdocuvier) • Diet: crustaceans, fish, seals, birds, smaller sharks, squid, turtles, sea snakes, and dolphins • ShortfinMako Shark (Isurusoxyrinchus) • Diet: cephalopods, bony fishes including mackerels, tunas, bonitos, swordfish, other sharks • Bull Shark (Carcharhinusleucas) • Diet: bony fish and sharks, including other bull sharks, but can also include turtles, birds, dolphins, terrestrial mammals, crustaceans and echinoderms • Zebra Shark (Stegostomafasciatum) • Diet: molluscs, crustaceans, small bony fishes, and possibly sea snakes • Hammerhead Shark (Sphyrnazygaena) • Diet: bony fishes and invertebrates, with larger individuals also feeding on sharks and rays • Bat Ray (Myliobatiscalifornica) • Diet: mollusks, crustaceans and small fish on the seabed • Stingray (Dasyatis sp.) • Diet: molluscs, crustaceans, and occasionally on small fish

4. (U) (L) Great White Shark (Carcharodon carcharias)

5. (U) (L) Tiger Shark (Galeocerdo cuvier)

6. (U) (L) Shortfin Mako Shark (Isurus oxyrinchus)

7. Bull Shark (Carcharhinus leucas)

8. Zebra Shark (Stegostoma fasciatum)

9. Hammerhead Shark (Sphyrna zygaena)

10. Bat Ray (Myliobatis californica

11. Stingray (Dasyatis sp.)