The late Neoproterozoic witnessed a revolution in the history of life: the transition from a microbial world to the one known today. The enigmatic organisms of the Ediacaran hold the key to understanding the early evolution of metazoans and their ecology, and thus the basis of Phanerozoic life. Crucial to interpreting the information they divulge is a thorough understanding of their taphonomy: what is preserved, how it is preserved, and also what is not preserved. Fortunately, this Period is also recognized for its abundance of soft-tissue preservation, which is viewed through a wide variety of taphonomic windows. Some of these, such as pyritization and carbonaceous compression, are also present throughout the Phanerozoic, but the abundance and variety of moldic preservation of body fossils in siliciclastic settings is unique to the Ediacaran. In rare cases, one organism is preserved in several preservational styles which, in conjunction with an increased understanding of the taphonomic processes involved in each style, allow confident interpretations of aspects of the biology and ecology of the organisms preserved. Several groundbreaking advances in this field have been made since the 1990s, and have paved the way for increasingly thorough analyses and elegant interpretations.

Macrostratigraphy is the study and statistical analysis of sediment packages that formed continuously at a specified scale of temporal resolution and that are bound by gaps recognizable at that same scale. The temporal ranges of gap-bound packages, compiled separately for different geographic locations, permit area-weighted, survivorship-based measures of rock quantity and spatio-temporal environmental continuity to be measured. Analytical basin fill models suggest that the parameters controlling sedimentation and sequence stratigraphic architecture, such as base level and sediment supply, can be detected quantitatively by macrostratigraphy.

Macrostratigraphic analysis of the marine sedimentary rock record in the United States at a temporal resolution of ~106 years reproduces most of the well-known Sloss sequences, but it also identifies two prominent megasequences, the Paleozoic and Modern megasequences, which are separated by a Permian-Triassic discontinuity and Phanerozoic minimum in rock quantity. Many short- and long-term features of the macroevolutionary history of marine animals are reproduced by macrostratigraphy, including 1) many patterns in genus richness, 2) patterns in rates of genus extinction and, to a lesser degree, rates of origination, and 3) patterns of extinction selectivity and the shifting relative richness of Sepkoski's Paleozoic and Modern evolutionary faunas. The extent to which macrostratigraphy reproduces the macroevolutionary history of marine animals transcends what is expected by geologically-controlled sampling biases. Instead, the processes which control the spatio-temporal dynamics of shelf sedimentation, including expansions and contractions of shallow epicontinental seas, have probably exerted a consistent influence on the macroevolutionary history of marine animals. Exploring the common cause hypothesis by putting fossils back into rocks and rocks into a new quantitative framework for physical environmental change holds considerable promise for paleobiology.

What is the range of time-averaging in the terrestrial vertebrate record? How are time-averaged assemblages distributed within the terrestrial vertebrate record? What are the implications of time-averaging for vertebrate paleobiological analysis?

Not all organisms have an equal chance of entering the fossil record. Previo—us attempts to quantify this percentage suggest that for megascopic marine organisms (megafauna), ∼30% would be predicted to leave no identifiable fossils. Here, that exercise is repeated for marine macrofauna, for which ∼80% are predicted to leave no identifiable fossils. The percentage will be far higher for meiofauna, the numerically most dominant marine animals. The organisms which are often most abundant in marine sediments, such as small polychaetes and nematodes, have essentially no fossil record. Yet such organisms are ecologically important in the modern oceans, and almost certainly were in ancient environments as well, so it is useful to consider the roles they play in different ecosystems. Insight into the evolution and paleoecology of these groups can be gained by using molecular divergence estimates to infer temporal origins combined with modern distributional and ecological data. As a case study, this approach is applied to the small and soft-bodied early animal fauna living under low levels of atmospheric oxygen that likely characterized the Precambrian.

The order Cetacea was the earliest, and is the most diverse mammalian group to adapt to a marine existence. The first fossil whales appear in the fossil record in the Middle Eocene. Interestingly, cetaceans developed in some ways that are parallel to earlier marine reptiles and appear to have filled some of their niches. Some cetaceans later re-adapted to fresh water.

Mass extinctions shape the history of life and can be used to inform understanding of the current biodiversity crisis. In this paper, a general introduction is provided to the methods used to investigate the ecosystem effects of mass extinctions (Part I) and to explore major patterns and outstanding research questions in the field (Part II). The five largest mass extinctions of the Phanerozoic had profoundly different effects on the structure and function of ecosystems, although the causes of these differences are currently unclear. Outstanding questions and knowledge gaps are identified that need to be addressed if the fossil record is to be used as a means of informing the dynamics of future biodiversity loss and ecosystem change.

Symbiotic relationships are common between algae and diverse lineages of corals, planktic foraminifera, benthic foraminifera, and bivalves as well as in many other groups that do not leave an extensive fossil record. Ancient photosymbioses can be inferred using various lines of inference including the morphology of the host, its habitat, rates of calcification, (which tend to be high in many photosymbiotic taxa), and the geochemistry of the host's shell. This survey shows that stable isotopes are reliable means of identification of photosymbioses in corals and planktic foraminifera, but are far less reliable in benthic foraminifera and bivalves. Organisms that increase their symbiont density proportionate to their own growth display a steep rise in shell δ13C, while organisms whose own growth exceeds that of their symbiont population display a far smaller effect on shell δ13C.

Large theropod dinosaurs like tyrannosaurs were the biggest land-living predators in earth history. Because of this, there has been considerable interest in reconstructing the paleobiology of these immense carnivores (Bakker, 1986; Bakker et al., 1988; Paul, 1988; Molnar and Farlow, 1990; Farlow et al., 1991; Abler, 1992; Farlow, 1993, in press; Horner and Lessem, 1993). In the present paper we consider a topic relevant to interpretations of how tyrannosaurs used their teeth during feeding: the incidence of wear surfaces on tyrannosaur teeth.

Within a family, genera are usually separated on the basis of their colonial structure. The periodic occurrence of transgeneric highly variable specific units (spectra) in the fossil record poses nomenclatural and phylogenetic problems. A detailed example among Jurassic montlivaltiids is presented in this paper involving the genera Montlivaltia, Coenotheca, Thecosmilia, Latiphyllia and Complexastrea. These spectra are related to peculiar unstable nonreefal environments and are characterized by the dominance of young stages of the colonial growth (astogeny). The arising nomenclatural difficulties are solved by way of spectral nomenclature which allows naming morphological types, as well as taxonomic units and keeping some stability within the general frame of nominal taxa. Genera correspond to grades (solitary, thamnasterioid, phaceloid, meandroid, cerioid) rather than clades and the colonial structure is a labile character. Several alternative phylogenetic hypotheses are proposed, among which, some can renew our vision of this group and emphasize that the iterative production of generic-level shapes is best explained by mean of heterochronic processes. It is suggested that testing of these hypotheses be extended to other families such as Microsolenidae, Stylophyllidae or Fungiidae.

Issues of scale are becoming increasingly important to paleobiological interpretations of the fossil record. Nevertheless, a number of biological processes display scale-independent behaviors. The effects of predation on the distribution of dense populations of epifaunal, suspension-feeding ophiuroids are scale-independent, at scales ranging from the microecological to the macroevolutionary. On a microecological scale (meters to kilometers, hours to days), dense ophiuroid populations are limited in shallow-water environments by predatory fishes and crabs. On a larger, ecological scale (tens to hundreds of kilometers, decades to centuries), circumstantial evidence indicates that oceanographically driven, multidecadal cycles of predator abundance determine the abundance of ophiuroids throughout the western English Channel. On a macroevolutionary scale (millions to tens of millions of years, global spatial scale), dense, autochthonous assemblages of ophiuroids declined in conjunction with the Mesozoic diversification of modern shell-crushing predators: teleostean fishes, decapod crustaceans, and neoselachian sharks. The sporadic reappearance of dense ophiuroid populations in a late Eocene, shallow marine deposit in Antarctica suggests that predator-prey relationships were disrupted as temperatures declined in the region at that time. Scale-independence is a useful model for explaining and predicting patterns of distribution of dense ophiuroid populations in time and space.

Ostracodes are bivalved Crustacea whose fossil shells constitute the most abundant and diverse metazoan group preserved in sediment cores from deep and intermediate ocean water depths. The ecology, zoogeography, and shell chemistry of many ostracode taxa makes them useful for paleoceanographic research on topics ranging from deep ocean circulation, bottom-water temperature, ecological response to global climate change and many others. However, the application of ostracodes to the study of climate change has been hampered by a number of factors, including the misconception that they are rare or absent in deep-sea sediments and the lack of taxonomic and zoogeographic data. In recent years studies from the Atlantic, Pacific, and Arctic Oceans show that ostracodes are abundant enough for quantitative assemblage analysis and that the geochemistry of their shells can be a valuable tool for paleotemperature reconstruction. This paper presents practical guidelines for using ostracodes in investigations of climate-driven ocean variability and the ecological and evolutionary impacts of these changes.

Taken as a whole, Devonian and Carboniferous floras represent vastly different evolutionary stages in the colonization of the Earth's surface by plants. When only Late Devonian and Mississippian floras are considered, however, all of the floral innovations that led to and characterize the increasingly sophisticated plant communities of the Carboniferous began in the Famennian. When examined carefully enough, the stratigraphical succession of floras at the Devonian/Mississippian boundary reveals a gradual decline of typical Late Devonian elements and an equally gradual increase of plant types that eventually characterize the Early Mississippian. Furthermore, significant floral changes occur throughout the Late Devonian as archaic genera, that originated in Middle Devonian or earlier, disappear and new types appear that will become important in the Mississippian. Within the Mississippian too, the earliest floras contain elements left over from the Devonian, but show the origins or expansions of groups that ultimately were of great importance in the Pennsylvanian.

Introducing Students to microfossils in the K-12 curriculum can be a rewarding and exciting experience for both instructor and student. Students, even those who collect fossils as a hobby, are generally unaware of microfossils. Exposure to microfossils opens up a whole new world of inquiry, and the extent to which that inquiry is developed can be adjusted to the grade-level and interest-level of the individual student.

The isotopic composition of fossil invertebrates contains a wealth of information about the physical and chemical environments of the ancient past. The exploitation of this biogeochemical archive by paleontologists began about 50 years ago with the realization that the ratios of oxygen isotopes in the shells and skeletons of marine organisms offered the potential to accurately reconstruct paleoenvironmental conditions, particularly temperature (Urey, 1947; Urey et al., 1951). With the introduction of the oxygen isotope paleotemperature methodology (Epstein et al., 1951, 1953; Epstein and Lowenstam, 1953), the field of “isotope paleontology” was born (Wefer and Berger, 1991).

This part of our course builds on the assumption that evolutionary change, although being stochastic in principle, is channeled by external and internal constraints to such a degree that it becomes quasi-predictable – or at least understandable. On this basis it makes sense to use the old methods of comparative morphology in the new framework of constructional morphology (Seilacher, 1970) in order to recognize patterns and to interpret them as trends and evolutionary pathways. For such an approach, bivalves are particularly suited:

1. they deviate little from a common design (for instance they never lost their shell).

2. their preservable hard parts adequately reflect the developmental biography of each individual.

3. their shell form expresses the compromise between developmental constraints and functional paradigm with little interference from soft part anatomy, physiology and biotic interactions.

4. they are diversified enough to provide many examples of parallel adaptations for model testing, particularly if we include the fossil record.

Many areas of paleontological enquiry, from questions of correlation to the characterization of macroevolutionary patterns, require estimates of taxonomic longevities. However, the fossil record is incomplete and biased and, as such, provides an incomplete sampling of true temporal ranges. “It is incomplete because many individuals, species, and higher taxa are not recorded as fossils. It is biased because the probability that a taxon is represented by a fossil is a function of the taxon's morphology, abundance, ecological habitat and spatial distribution, as well as the taxon's age.” (Pease, 1985, p. 272) To what extent do the inadequacies of the fossil record compromise our ability to estimate taxonomic longevities? What analytic methods exist for estimating true longevities from stratigraphic data, or for detecting situations where significant biases may be present? And perhaps most importantly, do analytic methods provide an effective way of dealing with the inadequacies of the fossil record?

Ecosystem Stability and taxonomic stasis are the opposite aspect in the history of life from ecosystem perturbation and reorganization, or extinction and origination. Naturally, change is more exciting than stasis, and change also is more useful in many ways as, for instance, in the development of biostratigraphic frameworks. Paleontological preference for geologically rapid change has gone so far that a fast evolving group of organisms has been used to create an orthostratigraphy (Orthochronologie of Schindewolf, 1950), which is claimed to be the “real” biostratigraphy. By implication, all other taxonomic groups are relegated to a secondary status of merely delivering “parastratigraphies,” which may be useful (locally or regionally), but are not the “real thing.” Ammonites, conodonts, foraminifera, and a few other taxa hold the distinction of being the “chosen” taxa, and it should be self-evident that only marine organisms qualify for this role. On the other hand, organisms on land always have been known to demonstrate coarser stratigraphic resolution. By implication, they might be more prone to ecosystem and taxonomic stasis over the long run. This, in itself, is an important observation.

Stalked crinoids (sea lilies) are not extinct, but are restricted to depths below 100 m and comprise over 80 living species. Over the past 20 years, a wide range of new information on the biology of stalked crinoids has been acquired from deep-sea photography and submersible studies. Taphonomic studies show that stalked crinoids can disarticulate and undergo breakage and abrasion without significant transportation, although crinoids can survive the rigors of transportation without damage if decay has not weakened connective tissues. Because stalks can remain articulated longer than crowns, the occurrence of articulated fossil crinoid stalks should not be interpreted as proof of rapid burial. Stalked crinoids are passive suspension feeders forming filtration fans oriented normal to bottom currents of low velocity. Mutable collagenous tissues comprising the ligaments of stalk, cirri, and arms are significant in providing variable stiffness that enables stalked crinoids to maintain elevation of the stalk and the filtration fan feeding posture. Regenerated arms and stalks lacking crowns suggest that stalked crinoids are subject to predation by fish in deep water, although predation pressure is likely lower than in shallow water.