Ichnology is the study of traces created in the substrate by living organisms. This is the first book to systematically cover basic concepts and applications in both paleobiology and sedimentology, bridging the gap between the two main facets of the field. It emphasizes the importance of understanding ecologic controls on benthic fauna distribution and the role of burrowing organisms in changing their environments. A detailed analysis of the ichnology of a range of depositional environments is presented using examples from the Precambrian to the recent, and the use of trace fossils in facies analysis and sequence stratigraphy is discussed. The potential for biogenic structures to provide valuable information and solve problems in a wide range of fields is also highlighted. An invaluable resource for researchers and graduate students in paleontology, sedimentology and sequence stratigraphy, this book will also be of interest to industry professionals working in petroleum geoscience.

Ichnology: Organism-Substrate Interactions in Space and Time

Were molecular data available for extinct taxa, questions regarding the origins of many groups could be settled in short order. As this is not the case, various strategies have been proposed to combine paleontological and neontological data sets. The use of fossil dates as node age calibrations for divergence time estimation from molecular phylogenies is commonplace. In addition, simulations suggest that the addition of morphological data from extinct taxa may improve phylogenetic estimation when combined with molecular data for extant species, and some studies have merged morphological and molecular data to estimate combined evidence phylogenies containing both extinct and extant taxa. However, few, if any, studies have attempted to estimate divergence times using phylogenies containing both fossil and living taxa sampled for both molecular and morphological data. Here, I infer both the phylogeny and the time of origin for Lissamphibia and a number of stem tetrapods using Bayesian methods based on a data set containing morphological data for extinct taxa, molecular data for extant taxa, and molecular and morphological data for a subset of extant taxa. The results suggest that Lissamphibia is monophyletic, nested within Lepospondyli, and originated in the late Carboniferous at the earliest. This research illustrates potential pitfalls for the use of fossils as post hoc age constraints on internal nodes and highlights the importance of explicit phylogenetic analysis of extinct taxa. These results suggest that the application of fossils as minima or maxima on molecular phylogenies should be supplemented or supplanted by combined evidence analyses whenever possible.

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Divergence time estimation using fossils as terminal taxa and the origins of Lissamphibia.

The fossil record of the earliest tetrapods (vertebrates with limbs rather than paired fins) consists of body fossils and trackways. The earliest body fossils of tetrapods date to the Late Devonian period (late Frasnian stage) and are preceded by transitional elpistostegids such as Panderichthys and Tiktaalik that still have paired fins. Claims of tetrapod trackways predating these body fossils have remained controversial with regard to both age and the identity of the track makers. Here we present well-preserved and securely dated tetrapod tracks from Polish marine tidal flat sediments of early Middle Devonian (Eifelian stage) age that are approximately 18 million years older than the earliest tetrapod body fossils and 10 million years earlier than the oldest elpistostegids. They force a radical reassessment of the timing, ecology and environmental setting of the fish-tetrapod transition, as well as the completeness of the body fossil record.

Tetrapod trackways from the early Middle Devonian period of Poland

Fluvial landscapes diversified markedly over the 250 million years between the Cambrian and Pennsylvanian periods. The diversification occurred in tandem with the evolution of vascular plants and expanding vegetation cover. In the absence of widespread vegetation, landscapes during the Cambrian and Ordovican periods were dominated by rivers with wide sand-beds and aeolian tracts. During the late Silurian and Devonian periods, the appearance of vascular plants with root systems was associated with the development of channelled sand-bed rivers, meandering rivers and muddy floodplains. The widespread expansion of trees by the Early Pennsylvanian marks the appearance of narrow fixed channels, some representing anabranching systems, and braided rivers with vegetated islands. We conclude that the development of roots stabilized the banks of rivers and streams. The subsequent appearance of woody debris led to log jams that promoted the rapid formation of new river channels. Our contention is supported by studies of modern fluvial systems and laboratory experiments. In turn, fluvial styles influenced plant evolution as new ecological settings developed along the fluvial systems. We suggest that terrestrial plant and landscape evolution allowed colonization by an increasingly diverse array of organisms.

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Palaeozoic landscapes shaped by plant evolution

The Frasnian/Famennian boundary interval in the South Polish-Moravian shelf basins: integrated event-stratigraphical approach

Mid Devonian carbonate platform development in the Holy Cross Mts. area (central Poland): new constraints from the conodont Bipennatus fauna

The age of the oldest tetrapod tracks from Zachełmie, Poland

Conodonts have been found in the Muschelkalk intervals in seven deep wells located in the central part of the Polish Middle Triassic basin. Total number of 80 specimens has been ascribed to 18 form-species. The presence of Paragondolella hanbulogi and Neogondolella balcanica is reported for the first time in Polish sections. Germanica and kockeli Zones of the late early Anisian, Pelsonian and ?earliest Illyrian have been found in the Lower Muschelkalk deposits. The Middle Muschelkalk corresponds to the Illyrian without its latest part, and to ?latest Pelsonian. Presence of the Zones .1, 2 and 4, found in the Upper Muschelkalk, allowed to correlate these deposits with the late Illyrian, Fassanian and earliest Longobardian. Analysis of geographical distribution of the investigated species revealed that only cosmopolitan conodonts occur in the Lower Muschelkalk whereas its upper part contains also forms endemic for the German Province.

Katarzyna Narkiewicz

Papers

Tetrapod trackways from the early Middle Devonian period of Poland

Mid Devonian carbonate platform development in the Holy Cross Mts. area (central Poland): new constraints from the conodont Bipennatus fauna

The age of the oldest tetrapod tracks from Zachełmie, Poland

Conodont biostratigraphy of the Muschelkalk (Middle Triassic) in the central part of the Polish Lowlands

Palaeoenvironments of the Eifelian dolomites with earliest tetrapod trackways (Holy Cross Mountains, Poland)