Continental trace fossils and museum exhibits - Geological Curators ...

of invertebrate ichnofossils has occurred only in thelast few decades.New Mexico is extremely rich in trace fossils, andhas a history of ichnological discovery and researchthat goes back to Degenhardt’s (1840) report of“grosse Fuss-Tritte von Vögeln” (large footprints ofbirds) in red sandstone near Socorro, New Mexico.Scientific study of New Mexico’s trace fossils hasintensified in the last few decades (e.g., Lucas andHeckert 1995, Lucas et al. 1998, 2005b), largelybecause the New Mexico Museum of Natural Historyand Science acts as a centre for this research.The New Mexico Museum of Natural History andScience opened its doors in 1986, with essentially nocollection at that time. The last two decades haveseen its fossil collections grow to more than 50,000catalogued specimens. In 1987, a private citizen,Jerry Paul MacDonald, discovered an exceptionallyrich Permian footprint site in the Robledo Mountainsnear Las Cruces, New Mexico (MacDonald 1992,1995). MacDonald’s collections from this and nearbysites were subsequently donated to the New MexicoMuseum of Natural History and became the nucleusof North America’s largest collection of Permiantrace fossils, which numbers nearly 2,000 cataloguedslabs with traces. During the last decade, Museumscientists Adrian Hunt and Spencer Lucas, andMuseum Research Associate Allan Lerner, have beenvery active in collecting and studying nonmarine(that is, continental) trace fossils, especially ofCarboniferous, Permian and Triassic age, so that theMuseum’s trace fossil collection continues to growin numbers and scientific importance.Coprolites from various geological periods, includingspecimens from local Devonian rocks, as well assome Pennsylvanian, Permian and Triassic coprolites,are also included in the collection.Trace fossil identification for the publicThe Cleveland area is rich in trace fossils. Theuppermost bedrock unit of much of northeasternOhio is the Famennian Chagrin Shale, a rock unit inwhich trace fossils are, in most locales, more abundantthan body fossils. Thus, trace fossils are some of themost common types of fossils brought to the Museumfor identification. However, most are not originallyidentified as trace fossils by members of the public.They are typically identified as body fossils of plantsor animals. The confusion with animals isunderstandable, as some forms do resemble animalimprints. Planolites, Cochlichnus? (Figure 1) andsome other trace fossils may resemble a snake. Indeed,such a ‘fossil snake’ was included in an exhibit ofrocks and fossils in one of J.T.H.’s elementary schoolclassrooms. The confusion with plants is alsounderstandable as, historically, many trace fossilswere initially described as plants (‘fucoids’).Bifungites is one taxon that has been brought in to theMuseum several times as a fossil plant to be identified.Cleveland Museum of Natural HistoryTrace fossil collectionThe Invertebrate Paleontology Collection of theCleveland Museum of Natural History containsnumerous invertebrate trace fossils, mostly from Ohioand nearby (but also not so nearby) states. Thisincludes suites of figured and cited specimens fromOhio (e.g., Stukel 1987, Hannibal 1997), WestVirginia (Bjerstedt 1989) and New Jersey(Gierlowski-Kordesch 1991). Most of the trace fossilsare housed in metal cabinets. This collection iscrowded, one reason being the large size of sometrace fossils. The figured and cited specimens aresegregated from the other trace fossils to make themmore accessible. The Vertebrate PaleontologyCollection contains a number of fossil footprints ofdinosaurs, most from the Triassic of Massachusetts,but also a number of trackways from thePennsylvanian of Ohio and the Permian of Arizona.-262-Figure 1. Sinusoidal invertebrate trace fossil Cochlichnus?,Cleveland Museum of Natural History (CMNH) 1314.Such elongate, sinuous ichnofossils are commonlyconfused with body fossils by the general public. Scale barequals 10 mm.