Fossil Beaked Whale Skull Donated to the Calvert Marine Museum
Total Page：16
File Type：pdf, Size：1020Kb
The ECPHORA• The Newsletter of the Calvert Marine Museum Fossil Club Volume 22 Number 1 March 2007 Fossil Beaked Whale Skull Donated to the Calvert Marine Museum Features On July 4th, 2004, James Wilbar was beachcombing at • Beaked Whale Skull low tide on Cedar Island and came upon the fossilized partial • Geology Timeline skull of a beaked whale, most similar to that of Mesoplodon longirostris (Cuvier 1823) (of Inside the Family Ziphiidae), Figure 1. Cedar Island is one of the • Miocene Tapir barrier islands on Virginia’s Tooth Atlantic coast near • Gavialosuchus Wachapreague. Skulls Mesoplodon longirostris is an extinct beaked whale known • Pathological from Miocene and Pliocene age Scallop sediments on both sides of the • C. megalodon North Atlantic Ocean. It has serrations also been found in the Pliocene • Pathological of Australia (Whitmore et. al, 1986). It has not yet been Dolphin Teeth determined what sediments this • Shark-bitten skull eroded from. Sea Cow Rib Consequently, the geologic age of this fossil is unknown. Figure 1. This fossilized partial skull of a beaked whale was found and donated to the Calvert Marine Museum by James Wilbar in memory of Margie L. Wilbar. It is tentatively assigned to the extinct beaked whale Mesoplodon longirostris (Cuvier 1823). The skull is shown in dorsal view with the front end of the skull pointing up. The bold arrow points to the ossified mesorostral “cartilage” indicating that this individual was male (in female beaked whales, the mesorostral cartilage does not ossify). The paired nostrils are also preserved behind (below) the mesorostral cartilage. CALVERT MARINE MUSEUM www.calvertmarinemuseum.com 2 The Ecphora March 2007 Until the discovery of this new skull, M. Godfrey, S. J., and A. J. Fuller. 2005. Fossil Beaked longirostris had only been known on the basis of Whales (Ziphiidae) from Calvert Cliffs. Bugeye the long narrow section of the skull comprising the Times: Quarterly Newsletter of the Calvert Marine snout (i.e., the rostrum). This more complete skull Museum 30(2). includes most of the bones over the eyes and those surrounding the blowhole (the nostrils). In fact, this Van Beneden, P.J., and P. Gervais. 1880. new specimen appears to represent the most Ostéographie des Cétacés vivant et fossiles. complete skull to date of this species of beaked Arthus Bertrand, atlas 64 pls. whale. Beaked whale fossils are rare (Godfrey and Whitmore, F. C. Jr., G. V. Morejohn, and H. T. Fuller, 2005), presumably because, like their living Mullins. 1986. Fossil beaked whales – descendants, they inhabited deep offshore marine Mesoplodon longirostris dredged from the ocean habitats and rarely ventured close to shore. Much bottom. National Geographic Research 2(1):47- remains to be learned from this discovery and it will 56. undoubtedly lead to a more detailed study. Stephen Godfrey ☼ The Paleontological Resources Preservation Bill (H.R. 554) There have been some concerns expressed Skeleton of a modern beaked whale, Mesoplodon. regarding House Bill H.R. 554 and the impact it will Modified from Van Beneden and Gervais (1880). have on fossil collecting. First and foremost, fossils have scientific and research value and should be valued as such. Any time a significant fossil is lost, stolen, or sold without study it is a great loss to the scientific community as well as the public at large. It is understood that The Paleontological Resources Preservation Bill (H.R. 554) was designed and introduced to protect as much as possible those fossils that are important for research and study that otherwise are stolen from federal lands. When read, the bill states that it covers only federal lands, not state, county, or private lands. As Calvert Cliffs does not fall under federal jurisdiction, this should not be a concern. It should also be known that it is Skull of Arnoux’s beaked whale, Berardius arnuxii. already illegal (and has been) to collect vertebrate The lower jaw has been lowered so as not to obstruct fossils from any federal land unless a permit has any of the lateral anatomy of the upper portion of the been acquired, there has been no change in that law. skull. As in Mesoplodon longirostris, and most other As for concerns regarding civil penalties, rewards, living beaked whales, the rostrum is toothless. In and forfeiture, this appears to be fairly routine in Berardius arnuxii, each side of the lower jaw sports bills and is not construed as being over the top in any only two small teeth. Modified from Van Beneden way. and Gervais (1880). Yasemin Tulu References Assistant Curator of Paleontology Calvert Marine Museum [email protected] Club website: http://www.calvertmarinemuseum.com/cmmfc/index.html Club email: [email protected] 3 The Ecphora March 2007 Another Tapir Tooth from the Maryland Miocene By Pamela C. Platt Recently, while walking on the beach at Scientists’ Cliffs (2/9/07), I found an unusual tooth that looked like the molar of a land mammal. David Bohaska identified it as a tapir tooth (Figures. 1-3). Several of his colleagues at the Smithsonian concurred (letter dated 2/12/07), and suggested that the tooth may be either a lower 4th premolar or a 1st molar. In terms of size, it is between the smaller Tapiravus and the larger extant genus Tapirus. Tapirs are rather primitive perissodactyls, which have evolved very little, unlike their horse or rhino relatives. They have a somewhat elongated proboscis and are quite short and stocky. They are Figure 2. Fossil tapir tooth collected by Pam Platt. forest dwelling animals that both browse and graze. Lower jaw bone fragments remain visible between Although all three groups first appeared in the the elongate roots of this tooth. Scan by S. Godfrey. Eocene, the horses and rhinos have evolved into much larger and more specialized animals (Savage & Long, 1989). Figure 3. Fossil tapir tooth in an occlusal view, collected by Pam Platt. Scan by S. Godfrey. Today four species of Tapirus survive: the Brazilian Tapir occurs in South America as a woodland animal; the Mountain Tapir occurs high in the Andes in mountain forests; Baird’s Tapir occurs from Mexico throughout Central America, and south to west of the Andes; and the Malayan Tapir inhabits rainforest areas from Burma and Thailand to Malaya Figure 1. Fossil tapir tooth collected by Pam Platt. (Mackinnon, 1984). Scan by S. Godfrey. Now extinct in North America, fossils of tapirs are very rare, although they occur over a large geographical area, and a broad geologic time, from Club website: http://www.calvertmarinemuseum.com/cmmfc/index.html Club email: [email protected] 4 The Ecphora March 2007 the Eocene to the Pleistocene. Fossil remains are judging from the localities where they have been often isolated teeth or bones. Tapir fossils have been found. found in the White River Formation of Nebraska and One interesting aspect of the new specimen is South Dakota, in several localities in Florida, and in that it has bone fragments attached to its roots. Keep other East Coast localities like New Jersey, the Gray you eyes open, all of you Beach Walkers, and look Site in Tennessee (Bohaska, pers. comm.), at Lee for the rest of the jaw! Creek in North Carolina, and in the Miocene of Maryland. Acknowledgements The author wishes to thank David J. Bohaska, Dr. Robert Emry, Dr. Clayton E. Ray, and Fred Grady of the Department of Paleobiology, National Museum of Natural History (the Smithsonian Institution) for identifying the tooth. I also wish to thank David for making several of the references available to me and for reading the manuscript. References Bohaska, D. 1989. Rare Tapirus tooth found at the Chesapeake Ranch Club. The Ecphora, Figure 4. This is an occlusal (chewing surface) view 5(3):1-2, and Personal Communication. of a fossilized upper second tapir premolar tooth (Tapirus veroensis). The original was collected as Gazin, C. L. & R. L. Collins. 1950. Remains of Land float by Debbie Rosser at Flag Ponds. Apparently, Mammals from the Miocene of the T. veroensis is a Pleistocene tapir. Notice that the Chesapeake Bay Region. Smithsonian ridges formed by the cusps resemble the Greek letter Miscellaneous Collections, 116(2):11-13. pi (π). This scan is of a cast of National Museum of Natural History 244777. Scan by S. Godfrey. Mackinnon, K. 1984. All the World’s Animals- Hoofed Mammals. D. Macdonald, Editor. The Smithsonian has several tapir teeth from Torstar Books, Inc., New York, N.Y. 160 pp. the Miocene of Maryland. In 1949, an upper jaw fragment containing two teeth was found at Marsh, O. C. 1871. Proc. Acad. of Nat. Sci. Chesapeake Beach (Gazin & Collins, 1950). This Philadelphia, Philadelphia, Pa. Vol. 23. specimen was thought to be Tapiravus validus, similar to an earlier specimen reported in the Savage, R. J. G. & M. R. Long. 1986. Mammal Miocene Marl of Cumberland County, New Jersey Evolution-An Illustrated Guide. Facts on File (Marsh, 1871). Another specimen (as yet Publications, New York, N.Y. 259 pp. unpublished) of a lower jawbone fragment with two ☼ teeth was also found at Chesapeake Beach. There is a large single tooth from Flag Ponds, and in 1989, CMMFC member Betty Cridlin collected an upper Rare "Prehistoric" Goblin Shark nd 2 molar at the Chesapeake Ranch Estates Caught in Japan (Bohaska, 1989). This somewhat larger tooth may represent the genus Tapirus. No genus has yet been suggested for the new tooth. All of these specimens http://news.nationalgeographic.com/news/2007/02/0 have been found as float. These teeth probably span 70209-goblin-shark.html all three formations of the Maryland Miocene, Submitted by Bruce Hargreaves ☼ Club website: http://www.calvertmarinemuseum.com/cmmfc/index.html Club email: [email protected] 5 The Ecphora March 2007 Fossil Gavialosuchus Skulls By: George F.