Shark Fossil Lab

Regression Equations: To convert tooth enamal height to total body length:

                Body Length (m) = 0.0209 + 0.1128(tooth enamal height (mm))

In the following table, the above computations have been done for you. For this table, N is the number of sharks of each species observed in the sample while the length is the total shark length in meters. Get the Data Sheet.

NOTE: Use class data to answer the following questions.

1. Why are teeth the most common fossil body part represented in your sample, and not some other structure?
2. What plant and animal ecological groups are missing from this fossil community? What are some potential explanations for their absence?
3. Theoretically reconstruct this prehistoric coastal marine ecosystem. Most of these fossils are from the highest carnivore trophic levels (except for most of the whales). Using the data related to modern-day sharks (in the table below), determine what species groups might have been present in the lower trophic (feeding) levels fed upon by your sharks.
4. Using the fossil teeth from extinct species, determine what food types might have been in their diets. Triangular teeth with serrated edges are better adapted for tearing or sawing large quantities of flesh from larger prey. Narrow pointed teeth are adapted for snagging fast-moving prey (such as bony fish).
5. Perform the species diversity calculations and report your results. Background information and a calculator can befound here.

Shark Species	Common Food Items
Bull, Carcharhinus leucas	Bony fish, small sharks
Mako, Isurus oxyrinchus	Bluefish or similar smaller bony fish, squid
Tiger, Galeocerdo cuvier	Sea turtles, bony fish, marine mammals, crustaceans
Great white, Charcarodon carcharias	Marine mammals, seals, dead whales, sharks and bony fish
Sand tiger, Eugomphodus taurus	Bony fish

Lemon Shark Negaprion brevirostris	Sand Tiger Carcharias taurus	Snaggletooth shark, Hemipristis elongatus	Hammerhead, genus Sphyrna	Ground Shark, Order Carcharhiniformes
Bull, Carcharhinus leucas	Mako, Isurus oxyrinchus	Tiger, Galeocerdo cuvier	Great white, Charcarodon carcharias	Sand tiger, Eugomphodus taurus

Click here to see the shark tooth key.
Tropical Paradise at the Cretaceous Poles? Read for content. (BIOLOGY MAJORS ONLY) This article shows how fossil evidence can be used to reconstruct an entire ecosystem.