Unusual preservation of small primaspid trilobites may provide a key to interpretation of an enigmatic, apparently organically textured surface or sedimentary structure in the subtidal Upper Ordovician (Katian) Kope Formation of northern Kentucky. A thin, elliptical lens of silty mudstone in the lower Kope Formation (Pioneer Valley submember, Southgate Member, C-1 Sequence) has several unique features mainly present on its basal surface, as a hyporelief, but also to a limited extent on the upper surface. Toward one end, the basal surface has sinuous fluting that terminates at the other end in a complex of conjoined, flattened, ellipsoidal or spatulate lobes that is partly overlain by an outlier of the primary lens. The basal surface has small-scale corrugations (3 to 4 mm wide) and polygonal reticulation variably developed. Articulated exoskeletons of small, spinose primaspid trilobites [Primaspis crosotus (Locke)] occur mostly with their ventral surfaces applied directly to the textured surfaces (i.e., dorsal side down). On some lobes the reticulate texturing wraps around from the basal to the upper surface and is covered with minute rounded pustules (∼ 0.3 mm). These enigmatic features are interpreted either as a recumbent microbial mat or an erect three-dimensional organism that was smothered and infilled by influx of silty sediment, preserved ultimately as a mold in hyporelief with trilobites in life position. Evidence for similar organic structures has not been previously reported from the Kope Formation. The taphonomic processes responsible for their preservation carry paleoenvironmental implications for possible microbial or macroalgal biotas within photic depths, and complex mediation of episodic depositional processes by organic biofilms or tissues.

Actualistic observations form the basis of many taphonomic studies in paleontology. However, surveys limited by environment or taxon may not be applicable far beyond the bounds of the initial observations. Even when multiple studies exploring the potential variety within a taphonomic process exist, quantitative methods for comparing these datasets in order to identify larger scale patterns have been understudied. This research uses modern bite marks collected from 21 of the 23 generally recognized species of extant Crocodylia to explore statistical and phylogenetic methods of synthesizing taphonomic datasets. Bite marks were identified, and specimens were then coded for presence or absence of different mark morphotypes. Attempts to find statistical correlation between trace types, marking animal vital statistics, and sample collection protocol were unsuccessful. Mapping bite mark character states on a eusuchian phylogeny successfully predicted the presence of known diagnostic, bisected marks in extinct taxa. Predictions for clades that may have created multiple subscores, striated marks, and extensive crushing were also generated. Inclusion of fossil bite marks which have been positively associated with extinct species allow this method to be projected beyond the crown group. The results of this study indicate that phylogenies can and should be further explored for use as predictive tools in a taphonomic framework.

We report on a paired set of manus and pes tracks from the lower part of the Upper Cretaceous Cantwell Formation in Denali National Park, Alaska, USA. The tridactyl track is bi-lobed in the ‘heel' and the morphology allows attribution to a hadrosaurid. While adult hadrosaurs typically reached body lengths of 1200 cm, the length of this Alaskan pes impression is approximately 11 cm, which provides a hip height estimate of approximately 44–45 cm for this trackmaker. The manus impression is approximately 3.6 cm wide and 2.75 cm long. While hypothesized through studies of skeletal anatomy, given the small body size of the hadrosaur that made these tracks, this paired set of impressions indicates that at least some juvenile hadrosaurs were facultative quadrupeds rather than obligatory bipeds.

Environmental parameters in Hamelin Pool, Shark Bay were investigated to characterize extrinsic factors that may be affecting stromatolite morphogenesis. Hamelin Pool, which evolved into a restricted environment during the last few millennia, sustains the world's most extensive and diverse assemblage of modern marine stromatolites. These stromatolites occur in a shallow nearshore facies belt covering over 100 km of coast. Temperature, salinity, water level, and current data collected between 2012 and 2014 have revealed previously undocumented regional and seasonal trends. Regional trends include increasing salinity, greater temperature range, and decreasing energy moving southward from Faure Sill and to the Nilemah Embayment. Seasonal trends reveal paradoxically increased salinities in wet winter months and decreased salinity in dry summer months. When paired with annual tidal cycles, these trends suggest the influx of low salinity groundwater along the Hamelin Pool shelf. Speculation on how the documented environmental parameters may affect stromatolite growth suggests potential impact on morphology, internal fabric, and stromatolite-building microbial communities. These insights into environmental pressures within a living stromatolite system provide a framework for understanding extrinsic factors affecting microbial communities and stromatolite development throughout Earth history.