The ECPHORA the Newsletter of the Calvert Marine Museum Fossil Club Volume 24 Number 3 September 2009
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The ECPHORA The Newsletter of the Calvert Marine Museum Fossil Club Volume 24 Number 3 September 2009 Features Tribute to Jeff Sparks Jeffrey Dale Sparks, 48 Tribute to Jeff Sparks Born December 31, 1960, in Riverside, California Paleo Camp Article Lamniform Vertebra Found Needless to say, it came as a complete shock to learn of the Inside passing of fossil collector extraordinaire, Jeff Sparks on September 10, Bill Palmer to Speak at 2009. In addition to being a member of the Calvert Marine Museum December Meeting Fossil Club, he was also a member of the American Fossil Federation and Dr. Jeremy Stone a fossil guide in North Carolina. When not at work as a carpenter, he was Donates Fossils out hunting for fossils or fishing, both of which he excelled at. I still recall when his daughters Amber and Jenna accompanied him on Trace Fossil collecting trips along Calvert Cliffs (image below). Paleo Quiz Meg Tooth Reunited Jeff donated some important fossils to our permanent collection, one of which, a deformed fossil whale vertebra, became the subject of a paper published by the Virginia Museum of Natural History (image below). Several of his other donations (stingray tail spines) are now the subject of ongoing research (see page 2). In the March 2009 issue of The Ecphora, I included a note on another fossil that Jeff donated to the CMM; a heavily “chewed upon” section of dolphin rostrum. We will miss Jeff but hope that his love for fossils and his passion for collecting them with great care will inspire all of us to do likewise. Stephen J. Godfrey CT scan image of a cetacean vertebra showing a compression fracture. CALVERT MARINE MUSEUM www.calvertmarinemuseum.com 2 The Ecphora September 2009 Stingray Tail Spine Jeff Sparks donated this stingray tail spine (CMM- V-3960). Here, it is shown coated with sublimed ammonium chloride to highlight surface detail. Photo by S. Godfrey. Articulated Fish Skeleton More recently, Jeff donated this partial, but articulated fish skeleton (CMM-V-4208) collected from along the Rappahannock River, Virginia. It has yet to be identified and fully prepared. Photo by S. Godfrey. Club website: http://www.calvertmarinemuseum.com/cmmfc/index.html Club email: [email protected] 3 The Ecphora September 2009 Editor’s Note: The following article was submitted teeth we found during that trial were recorded as to The Ecphora by Maryland Middle School students Sample One. After that we searched on our own who attended the Maryland Summer Center for throughout the entire 50 ft-long area. This method Paleontology. I have edited their submission lightly. usually yielded the most teeth. Those teeth were recorded as Sample Two. We then took a lunch break and then returned to our search. Sample Three The Present is the Key to the Past was a more relaxed search, but using this method we found 4 Megalodon teeth which is an incredible find. At the end of the day, we traveled back to Mill Creek People come to beaches of Southern Middle School and classified every single tooth. Maryland everyday to find shark teeth. Many don’t Many were used for an exhibit we made for the realize that the teeth they are finding are 8-18 million Calvert Marine Museum and Calvert County Middle years old. These teeth are from the Miocene epoch, a Schools. period of time when Calvert County was intermittently completely underwater. The Miocene Background of Calvert Cliffs Sea was full of fish, including numerous skates, rays, Calvert Cliffs are Maryland’s own key to the and sharks. past. Since 1770, they have become a popular During the summer of 2009, 20 students, landmark attracting tourists and scientists alike. from all around the state of Maryland, came together Through scientific studies and just plain to investigate the past, as a part of the Maryland beachcombing, the Cliffs have yielded 624 different Summer Center for Paleontology. species of marine life from the Miocene epoch. In this center, students worked with the staff Every once in a while, a mastodon (an extinct kind of the Calvert Marine Museum and collected fossil of elephant) or marine mammal is found protruding shark teeth from three different beaches (each from a from the cliff. Most teeth and fossils erode off the different geological formation) and studied them to cliffs due to the waves and rain. But with 35 miles find out what types of environments existed in of shoreline, there are more than enough fossils to be Calvert County during the Miocene. From these found. The three cliff formations: Calvert, fossils, the students learned about the different Choptank, and St. Marys, were deposited in that marine life and environmental conditions that existed order 8 to 18 million years ago when Calvert County within the Miocene Sea. spent much of that time at the bottom of a shallow In this article, students focused on the arm of the Atlantic Ocean. Digging in the cliffs is question that was drawn based on our scientific dangerous and should only be done by a qualified studies : team. If a large fossil is found, contact the Calvert Marine Museum. They will collect the fossil to “Based upon the teeth collected, display in the museum, giving full credit to the what can you conclude about the marine finder. If you would like to search on private environments in Southern Maryland beaches, obtain full permission by the owner of the during the Miocene epoch?” land. The public beaches do have large amounts of teeth. A good time to look for teeth is after a Methods rainstorm as it probably will wash away parts of the During our three trips to beaches all along cliff, bringing down teeth. Calvert Cliffs, we used three different sampling The three cliff formations are Calvert, techniques. Before we began looking for the teeth, Choptank, and St. Marys. We visited beaches in all each team of four students measured out three formations. We first visited St. Marys, the approximately 50 ft of workspace. Once that was youngest formation, at Cove Point Beach. Next, we finished, each team filled a five-gallon bucket with visited Choptank at Plum Point Beach (which also sand, shells, and gravel from within the measured includes large exposures of the Calvert Formation). area. We used box-strainers, sifters, and sometimes Our final trip took us to the Calvert Formation, being our hands to go through the bucket of matrix. The the oldest, at Brownie’s Beach. Club website: http://www.calvertmarinemuseum.com/cmmfc/index.html Club email: [email protected] 4 The Ecphora September 2009 and temperate waters usually warmer than 16 degrees C. They could go to depths of 500 meters. Brownie’s Today’s Makos prefer clear water over turbid water Beach and this may have been the case during the Miocene as well. Miocene Makos fed upon bony fish, squid, a variety of sharks, rays, and small crustaceans. Larger Plum Point Mako sharks may have attacked dolphins which Beach were abundant during the Miocene. Makos may have attacked from below as do modern day members of this species. While we didn’t find many Hammerhead shark teeth, we did find some. They tend to prefer temperate and tropical waters. They can live at depths up to about 80 meters. They eat rays, smaller fish, octopuses, squid, and crustaceans. We didn’t Cove Point find very many Cow sharks teeth either; they tend to Beach live in temperate and deeper waters. They fed upon bony fish, sharks, rays, and crustaceans. The Sharp- Background of Species nose shark prefers a water temperature of either Overall, we found 12 different types of tropical or temperate locations. They eat bony fish sharks from our collecting trips at Brownies Beach, and invertebrates. The Angel shark prefers the same Plum Point Beach, and Cove Point Beach (see the habitat as the cow shark. They eat mollusks and table below for a summary of these findings). The crustaceans. The Megalodon needed a lot a room Snaggletooth shark probably had a diet of bony and salty tropical waters. They ate whales, seals, and fish, as well as other sharks, and rays. It was probably anything else they desired. The Thresher probably relatively common near shore. Its upper sharks lived in coastal waters and ate schooling fish teeth were adapted for cutting, while the lower teeth or squid. Whale Sharks lived in tropical waters and are used for grasping and holding prey. The ate small fish, plankton, or algae. Requiem sharks are a large group of sharks including the Bull, Dusky, Silky, Gray. The Results Requiem sharks habitat consisted of turbid waters, Species Cove Plum Brownie’s Total lagoons, estuaries, coast lines, and reef environments Point Point Beach for all to a depth of about 150 meters. Like their living beaches counterparts, their diet consisted of a variety of Snaggletooth 15% 7% 2% (38) 5% animals such as bony fish, turtles, seals, crabs, and (74) (32) (144) squid. For the Bull shark, hunting may have occurred Requiem 69% 72% 81% 77% in both salt and fresh water habitats as is common (342) (329) (1248) (1919) behavior in Bull sharks today. Tiger 9% 12% 2% (45) 6% The Tiger shark can be found anywhere (49) (56) (150) from reefs to turbid estuarine environments to a Sand Tiger 1% 3% 10% (166) 7% depth of about 70 meters. The Tiger shark would eat (6) (15) (187) almost anything in its path. To hunt, it moved into Mako 4% 1% 4% (7) 1% (36) shallow waters at night. A Sand Tiger’s optimal (20) (9) habitat would have included sandy coastal areas, a Hammerhead 2% 1% 0% (0) >1% shallow bay, an estuary, a rocky reef or a tropical (1) (3) (4) reef.