Paleobiology Commons^™

Belowground Rhizomes In Paleosols: The Hidden Half Of An Early Devonian Vascular Plant, Jinzhuang Xue, Zhenzhen Deng, Pu Huang, Kangjun Huang, Michael J. Benton, Ying Cui

Ying Cui

The colonization of terrestrial environments by rooted vascular plants had far-reaching impacts on the Earth system. However, the belowground structures of early vascular plants are rarely documented, and thus the plant−soil interactions in early terrestrial ecosystems are poorly understood. Here we report the earliest rooted paleosols (fossil soils) in Asia from Early Devonian deposits of Yunnan, China. Plant traces are extensive within the soil and occur as complex network-like structures, which are interpreted as representing long-lived, belowground rhizomes of the basal lycopsid Drepanophycus. The rhizomes produced large clones and helped the plant survive frequent sediment burial in well-drained soils …

Examining The Use Of Amazon’S Mechanical Turk For Edge Extraction Of The Occlusal Surface Of Fossilized Bovid Teeth, George K. Thiruvathukal, Gregory J. Matthews, Maxwell P. Luetkemeier, Juliet K. Brophy

George K. Thiruvathukal

In order to reconstruct environments associated with Plio-Pleistocene hominins in southern Africa, researchers frequently rely upon the animals associated with the hominins, in particular, animals in the Family Bovidae. Bovids in southern Africa are typically identified by their teeth. However, identifying the taxon of a bovid tooth is challenging due to various biasing factors. Furthermore, inaccurate identification of fossil bovids can have significant consequences on the reconstructed paleoenvironment. Recent research on the classification of bovid fossil teeth has relied on using elliptical Fourier analysis to summarize the shape of the outline of the occlusal surface of the tooth and the …

New Genera And Species Of Fossil Marine Amioid Fishes (Actinopterygii, Holostei) From The Late Cretaceous Agoult Locality In Southeastern Morocco, Mark V. H. Wilson, Alison M. Murray, Terry C. Grande

Terry Grande

No abstract provided.

Rapid Formation Of Framboidal Sulfides On Bone Surfaces From A Simulated Marine Carcass-Fall, Laura Vietti, Jake Bailey, David Fox, Raymond Rogers

Raymond Rogers

No abstract provided.

Microstratigraphic Analysis Of Burrow-Reworked Dinosaur Track Bed At Joanna's Track Site, Cretaceous Glen Rose Formation, Glen Rose, Texas, Michael Blair, Benjamin Dattilo, Anthony Martin, James Farlow

Benjamin F. Dattilo

Although dinosaur trackways are common in the Cretaceous Glen Rose Formation of Texas, the recently discovered Joanna track site illustrates a unique ichnological relationship where dinosaur tracks were disrupted by invertebrate burrows made long after burial. In an effort to document the precise sequence of events, we described the interval from 0.3 m below the track layer through 2.7 m above it in a vertical outcrop adjacent to the track site, focusing on the 70-cm of strata immediately above the track horizon. An 8-meter N-S cross-section of this 70-cm interval was power-washed, examined for trace fossils, body fossils, and lithology …

Push Me – Pull You: Experimental Biomechanics Of Immobile Suspension Feeders On Soft Substrates, Roy Plotnick, Benjamin Dattilo, Joshua Corrie, Daniel Piquard, Jennifer Bauer

Benjamin F. Dattilo

Immobile suspension feeders on soft substrates (ISOSS; Thayer 1979) although rare in modern marine habitats, were relatively common in the Paleozoic. Numerous Paleozoic taxa have been interpreted as dwelling on soft unconsolidated sediments and possessing morphologic features that either anchor them to the sea floor (e.g., crinoid holdfasts) or prevent them from sinking in (strophomenid brachiopods). Thayer (1975) reviewed the morphologic adaptations for forms living on soft-muddy bottoms and provided a quantitative expression of the static stresses involved. The same quantitative expression can also be used to describe the forces involved in anchoring. With the exception of Leighton and Savarese …

An Unusual Association Of Pseudolingula And Rafinesquina From The Upper Ordovician Of Ohio, Benjamin Dattilo, Rebecca Freeman, Bryan Utesch, Steve Felton, John Pojeta

Benjamin F. Dattilo

Late Ordovician members of Order Lingulida, for the most part, resemble modern lingulids in their infaunal habits and marginal habitats. Pseudolingula, a common Cincinnatian form, is often found preserved in burrows in life position, and as such, it could probably escape moderate sediment accumulations. An unusual association of thousands of specimens of the lingulate Pseudolingula and hundreds of the strophomenid Rafinesquina in the Upper Ordovician of the Cincinnati, Ohio region presents an interesting case. This association occurs on 4-square-meter exposure of a 10 cm shell bed in the Fairview Formation at Harsha Lake, Ohio. The bed is covered with Rafinesquina …

Stirred Not Shaken: Using Taphonomy To Reconstruct Paleoecological Succession And Taphonomic Feedback In A Cincinnatian (Ordovician, Ohio) Storm-Disturbed Shell Bed, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Steve Felton, John Pojeta

Benjamin F. Dattilo

Walker and Alberstadt’s 1975 idea that a single shell bed contains a record of ecological succession has seemingly been refuted through stratinomic studies. These studies suggest that fossils are destroyed and accumulations are reworked by storms to the point of obliterating any record of successional-scale changes in faunas. Therefore storm-disturbed shell beds are not considered ideal for reconstruction of paleoecological succession.

Nevertheless, a storm-winnowed shell bed from the Fairview Formation, Ohio preserves a wide variety of shells in a range of taphonomic conditions that reveal succession-like changes. Exceptionally-preserved lingulid brachiopods found as intact pyrite-lined spar-filled shells rule out the final …

Dinosaur Tracksites Of The Paluxy River Valley (Glen Rose Formation, Lower Cretaceous), Dinosaur Valley State Park, Somervell County, Texas., James O. Farlow, Mike O'Brien, Glenn J. Kuban, Benjamin F. Dattilo, K. T. Bates, Peter L. Falkingham, L. Pinuela, Amanda Rose, A. Freels, C. Kumagai, Courtney Libben, Justin Smith, J. Whitcraft

Benjamin F. Dattilo

In 1940 R.T. Bird of the American Museum of Natural History collected segments of a sauropod and a theropod trackway from a site in the bed (Glen Rose Formation; Lower Cretaceous) of the Paluxy River, in what is now Dinosaur Valley State Park (Glen Rose, Texas, USA). However, Bird left undocumented thousands of other dinosaur footprints from this and other Paluxy tracksites. In 2008 and 2009 our international team carried out fieldwork to create detailed photomosaics of extant Paluxy tracksites, using GIS technology to combine these with historic maps and photographs. We also made photographs, tracings, LiDAR images, and measurements …

The Curse Of Rafinesquina: Negative Taphonomic Feedback Exerted By Strophomenid Shells On Storm-Buried Lingulids In The Cincinnatian (Katian, Ordovician) Series Of Ohio, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Steve Felton, John Pojeta

Benjamin F. Dattilo

Thousands of lingulid brachiopods were found clustered beneath hundreds of individual valves of the strophomenid brachiopod Rafinesquina in the Upper Ordovician of Ohio. This association suggested a relationship between the two brachiopods, but the nature of this relationship was unclear. We utilized serial thin sectioning to examine these brachiopods and to determine the origin of the bed in which they were found. Sedimentary structures, mixed taphonomies, and stratigraphic and paleogeographic setting suggest that the lingulids occupied a hiatal concentration that had previously been reworked, but not significantly transported, by tropical storms. The final burial event was a storm that exhumed …

Remarkable Preservation Of A New Genus And Species Of Limuline Horseshoe Crab From The Cretaceous Of Texas, U.S.A., Rodney Feldman, Carrie Schweitzer, Benjamin Dattilo, James Farlow

Benjamin F. Dattilo

A single specimen, part and counterpart of a carapace, of a horseshoe crab from the Lower Cretaceous (Albian) Glen Rose Formation in north-central Texas, forms the basis for the definition of a new genus and species, Crenatolimulus paluxyensis. The discovery represents only the fifth limuline known from the Cretaceous. Its preservational style is remarkable in that the carapace exterior is faithfully replicated by a massive overgrowth of serpulid worms.

The “Passive Implanter” Strategy Of The Adult Ordovician Brachiopod, Platystrophia Ponderosa., Sadye Howald, Benjamin Dattilo

Benjamin F. Dattilo

Platystrophia ponderosa is found throughout the Maysvillian Strata of the Cincinnati Ordovician. This species thrived in a high energy environment with only muddy shell gravels, and no solid substrates for pedicle attachment. Our growth-series studies show juveniles of this species had large pedicle openings, thin shell, small size, nearly flat shape, and shallow sinus/sulcus. In contrast, the adults had relatively small pedicle openings obstructed by a large beak, secondary thickening of the pedicle valve making it considerably thicker than the brachial valve, large size (up to 4cm in diameter), spherical shape, and deep sinus/sulcus. The morphological characteristics of the adult …

A Quantitative Paleoecological Approach To High-Resolution Cyclic And Event Stratigraphy: The Upper Ordovician Miamitown Shale In The Type Cincinnatian, Benjamin Dattilo

Benjamin F. Dattilo

No abstract provided.

How Many Track Horizons Are Exposed At Dinosaur Valley State Park? Stratigraphy Of The Cretaceous Glen Rose Formation Track Sites Of The Paluxy River, Glen Rose, Texas, Benjamin Dattilo, Sadye Howald, James Farlow, Anthony Martin

Benjamin F. Dattilo

The dinosaur tracks of the Glen Rose Formation in the Paluxy River at Dinosaur Valley State Park are among the best preserved and most abundant in the world. While many track sites are easily correlated to the Main Tracksite, others, especially those at the extreme ends of the park, are differently preserved and not obviously correlated. To count track horizons, several stratigraphic sections were measured along the river from upstream at the McFall Ledge Site to 7.6 km downstream at the County Road 1001 crossing (3.1 km linear distance). These reveal 6 meters of strata separating two track-bearing horizons exposed …

Stop Clinging! –How The Ordovician Brachiopod (Fka Platystrophia) Vinlandostrophia Ponderosa Outgrew Its Mid-Life Attachment Crisis, Benjamin Dattilo, Sadye Howald

Benjamin F. Dattilo

The high-energy nearshore environment and muddy shifting shell gravels recorded in Maysvillian strata of the Cincinnati Ordovician might seem particularly inhospitable to brachiopods, which generally require solid surfaces for attachment. Nevertheless, Vinlandostrophia ponderosa thrived and even characterizes these facies. A preliminary study of growth series suggests that, like the full-grown stages of related species, smaller V. ponderosa were attached by pedicle. Smaller specimens have a large pedicle opening, a nearly flat shape, thin shell, and a shallow sinus/sulcus, leaving the commissure nearly flat. These characteristics are consistent with strong, erect pedicle attachment, even stronger than found in related species, whose …

Sedimentology And Microstratigraphy Of A Cincinnatian Edrioasteroid Obrution Deposit., Aaron Morse, Benjamin Dattilo, David Meyer, Lydia Mark, Michael Harrison

Benjamin F. Dattilo

The Manchester edrioasteroid pavement is a shell layer in mudrock from the Corryville Formation (U. Ordovician, Maysvillain). No previous studies have examined sediments that buried Cincinnatian edrioasteroid pavements. To address this problem, a 16 cm thick stratigraphic sample measuring 90 cm by 30 cm was collected with a plaster jacket, dried for 2 years, then encased in fiberglass for dry cutting into slabs 2-4 cm thick. These were hardened with epoxy and polished dry with sandpaper. A prepared slab was sent to Bruker AXS for analysis using the M4 Tornado µ-XRF.

Delicate colonies of bryozoans, embedded in mudrock were found …

The Orientation Of Strophomenid Brachiopods On Soft Substrates, Roy Plotnick, Benjamin Dattilo, Daniel Piquard, Jennifer Bauer, Joshua Corrie

Benjamin F. Dattilo

Strophomenid brachiopods have long been interpreted as ‘‘snowshoe’’ strategists, with their flattened concavoconvex valves providing resistance to foundering in very soft sediments. There has been a sharp difference of opinion in whether the shells were oriented with their convex or their concave surface in contact with the sediment. This study, along with independent evidence from sedimentology, ichnology, and morphology, indicates that the strophomenids lived with their shells concave down (convex up). Experiments indicate the force required to push shells into soft cohesive muds is much greater for the convex up than for the convex down orientation. Forces also increase with …

An Enigmatic Lobate Mat-Like Fossil(?) In The Kope Formation (Upper Ordovician), Kenton County, Kentucky, Ron Fine, Carlton Brett, Benjamin Dattilo, David Meyer

Benjamin F. Dattilo

A new, enigmatic, large fossil(?) object from a thin silty mudstone bed (up to 3 cm thick) underlain by siltstone was excavated from the lower Kope Formation (Economy Member, basal Pioneer Valley submember) near Covington, KY. The excavated object is roughly elliptical in outline, over 2 m long, with a parallel-fluted structure at one end that terminates in a complex of conjoined, flattened, ellipsoidal or spatulate concretion-like lobes at the other end. The lobes are about 10 cm and range to 45 cm long. Internally, some lobes show lamination, sometimes convoluted. The most perplexing feature of the lobe-like structures is …

Fine-Scale Lithologic Variations In Late Ordovician (Katian) Pertidal Depositions Of The Kentucky Bluegrass Suggest Sea-Level Fluctuations As The Primary Mechanism For Type Cincinnatian Meter-Scale Cycles., Sasha Mosser, Thomas Schramm, Benjamin Dattilo, Carlton Brett, Rebecca Freeman, Michael Blair

Benjamin F. Dattilo

Late Ordovician peritidal facies of central Kentucky are laterally equivalent to cyclic subtidal facies of the Cincinnati region but correlation details, and causes of cyclicity are poorly understood. If type Cincinnatian shale-limestone (meter scale) cycles were driven by sea-level fluctuations then equivalent peritidal facies should be cyclic. Likewise, the same magnitude of base level change should result in greater environmental variability in these shallow facies. If cycles are of Milankovitch origin, it should be reflected in cycle duration. We attempt to test these predictions by examining litho, sequence, and macro-biostratigraphic evidence at Point Leavell, KY and other localities. Exposures at …

Gape, Feeding Currents And Valve Snapping In Thecidellina Meyeri From Curaçao, Netherlands Antilles: Biomechanical Analogue For Trace-Making Paleozoic Strophomenates?, Benjamin Dattilo, Tanya Del Valle, David Meyer, Aaron Morse

Benjamin F. Dattilo

The ability of Ordovician strophomenates Sowerbyella and Rafinesquina to move sediment and create moat-like depressions has led to questions about mechanisms. Anatomical studies suggest a gape of more than 45°, likely critical to trace-making abilities. Strophomenates are extinct, but thecidellinids are reasonably good analogues; they also gape widely and have a similar lophophore structure. They differ in their small size, 3 - 5 mm, lack of concavo-convex form, and by pedicle valve cementation. Nevertheless, their physiology could illuminate biomechanical constraints on strophomenate-sediment interactions. For this study, we analyzed 1 hour of video showing 30+ specimens collected with the fragment of …

The Brachiopod Trap: What Their Oldest (Upper Ordovician, Ohio) Failed Escape Burrows Tell Us About The Evolution Of Burrowing In Lingulids, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Bryan Utesch, Steve Felton, John Pojeta

Benjamin F. Dattilo

Infaunal organisms living in shallow marine settings are vulnerable to exhumation during storms or entombment by storm-deposited sediments. Cambrian­–Early Ordovician lingulids included epifaunal as well as possible infaunal forms. However, many epifaunal forms became extinct during the Middle Ordovician, and Late Ordovician lingulids were similar in their infaunal habits and marginal habitats. Modern infaunal lingulids are able to reorient themselves after burial in sediments, but it is unclear when this ability evolved. Initial burrowing of juvenile lingulids, as well as re-burrowing of exhumed modern lingulids involves digging downwards and then back up in a u-shape, but successful escape burrowing involves …

First Cranial Remains Of A Gondwanatherian Mammal Reveal Remarkable Mosaicism, Daivid Krause, Simone Hoffmann, John Wible, Christopher Kirk, Julia Schultz, Wighart Von Koenigwalds, Joseph Groenke, James Rossie, Patrick O'Connor, Erick Seiffert, Elizabeth Dumont, Waymon Holloway, Raymond Rogers, Lydia Rahantarisoa, Addison Kemp, Haingoson Andriamialison

Raymond Rogers

No abstract provided.

The “Curse Of Rafinesquina:” Negative Taphonomic Feedback Exerted By Strophomenid Shells On Storm-Buried Lingulids In The Cincinnatian Series (Katian, Ordovician) Of Ohio, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Steve Felton, John Pojeta

Benjamin F. Dattilo

Taphonomic feedback is the idea that accumulation of organic remains either enhances the habitat for some organisms (positive taphonomic feedback), and/or degrades the habitat for others (negative taphonomic feedback). Examples of epibionts living on skeletal remains are direct evidence of positive taphonomic feedback. Disruption of infaunal burrowing activities by skeletal fragments is an example of negative taphonomic feedback; direct fossil evidence of this phenomenon has not been documented previously. Infaunal organisms are vulnerable to exhumation or entombment during storms, but organisms that burrow can also re-establish viable life positions subsequently. For example, when modern lingulids re-burrow after exhumation, they first …

A New Eusuchian Crocodyliform With Novel Cranial Integument And Its Significance For The Origin And Evolution Of Crocodylia, Casey Holliday, Nicholas Gardner

Nicholas Gardner

Crocodyliforms were one of the most successful groups of Mesozoic tetrapods, radiating into terrestrial, semiaquatic and marine environments, while occupying numerous trophic niches, including carnivorous, insectivorous, herbivorous, and piscivorous species. Among these taxa were the enigmatic, poorly represented flat-headed crocodyliforms from the late Cretaceous of northern Africa. Here we report a new, giant crocodyliform from the early Late Cretaceous (Cenomanian) Kem Kem Formation of Morocco. Represented by a partial braincase, the taxon has an extremely long, flat skull with large jaw and craniocervical muscles. The skull roof is ridged and ornamented with a broad, rough boss surrounded by significant vascular …

Declining Atmospheric Co2 During The Late Middle Eocene Climate Transition, Gabriela Doria, Dana Royer, Alexander Wolfe, Andrew Fox, J. Westgate, David Beerling

Gabriela Doria

No abstract provided.

Race And Human Diversity: A Biocultural Approach, Robert Anemone

Robert L. Anemone

No abstract provided.

Gis And Paleoanthropology: Incorporating New Approaches From The Geospatial Sciences In The Analysis Of Primate And Human Evolution, Robert L. Anemone, Glenn C. Conroy, Charles W. Emerson

Robert L. Anemone

The incorporation of research tools and analytical approaches from the geospatial sciences is a welcome trend for the study of primate and human evolution. The use of remote sensing (RS) imagery and geographic information systems (GIS) allows vertebrate paleontologists, paleoanthropologists, and functional morphologists to study fossil localities, landscapes, and individual specimens in new and innovative ways that recognize and analyze the spatial nature of much paleoanthropological data. Whether one is interested in locating and mapping fossiliferous rock units in the field, creating a searchable and georeferenced database to catalog fossil localities and specimens, or studying the functional morphology of fossil …

Cenozoic Mass Extinctions In The Deep Sea; What Disturbs The Largest Habitat On Earth?, Ellen Thomas

Ellen Thomas

No abstract provided.

Longitudinal Study Of Dental Development In Chimpanzees Of Known Chronological Age: Implications For Understanding The Age At Death Of Plio-Pleistocene Hominids, Robert Anemone, Mark Mooney

Robert L. Anemone

Reconstruction of life history variables of fossil hominids on the basis of dental development requires understanding of and comparison with the pattern and timing of dental development among both living humans and pongids. Whether dental development among living apes or humans provides a better model for comparison with that of Plio-Pleistocene hominids of the genus Australopithecus remains a contentious point. This paper presents new data on chimpanzees documenting developmental differences in the dentitions of modern humans and apes and discusses their significance in light of recent controversies over the human or pongid nature of australopithecine dental development. Longitudinal analysis of …

Biogeography Of The Late Paleocene Benthic Foraminiferal Extinction, Ellen Thomas

Ellen Thomas

During the Late Paleocene Thermal Maximum (LPTM) benthic foraminifera at middle bathyal and greater depths suffered extinction of 30-50% of species during a few thousand years. Extinction was less severe at neritic to upper bathyal depths, where temporary changes in faunal composition prevailed. Pre-extinction deep-sea faunas were cosmopolitan and diverse, and contained heavily calcified species. Immediate post-extinction faunas were more variable geographically, exhibited low diversity, and were dominated by thin-walled calcareous or agglutinated taxa, possibly because CaCO3 dissolution increased globally from neritic to abyssal depths just before the extinction. These assemblages were dominated either by long-lived taxa such as Nuttallides …