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The life of paleontologist Charles R. Marshall is discussed, focusing on his professional contributions in stratigraphic geological research. Charles R. Marshall received the Charles Schuchert Award in October 1999.

The article discusses the study on data set of 1450 species from 18 fossilferous sections in varied paleoenvironmental settings in South China and northern pre-Gondwanan region, integrating it with high-precision geochronologic data for evaluation of rapidity of largest Phanerozoic mass extinction. Constrained optimization (CONOP) was applied for reduction of Signor-Lipps effect. The study indicates occurrence of abrupt extinction of 62 percent of species within 200 thousand years (Kyr).

YIN HONGFU, Ed. Oxford University Press, New York, 1994. xiv, 370 pp., illus. $120 or £80. Oxford Biogeography Series, 8. Translated from the Chinese edition (1988). Grappling with the tectonic [...]

Niche construction theory (NCT) explicitly recognizes environmental modification by organisms ("niche construction") and their legacy over time ("ecological inheritance") to be evolutionary processes in their own right. Here we illustrate how niche construction theory provides useful conceptual tools and theoretical insights for integrating ecosystem ecology and evolutionary theory. We begin by briefly describing NCT, and illustrating how it differs from conventional evolutionary approaches. We then distinguish between two aspects of niche construction-environment alteration and subsequent evolution in response to constructed environments-equating the first of these with "ecosystem engineering." We describe some of the ecological and evolutionary impacts on ecosystems of niche construction, ecosystem engineering, and ecological inheritance, and illustrate how these processes trigger ecological and evolutionary feedbacks and leave detectable ecological signatures that are open to investigation. Finally, we provide a practical guide to how NCT could be deployed by ecologists and evolutionary biologists to explore eco-evolutionary dynamics. We suggest that, by highlighting the ecological and evolutionary ramifications of changes that organisms bring about in ecosystems, NCT helps link ecosystem ecology to evolutionary biology, potentially leading to a deeper understanding of how ecosystems change over time. [ABSTRACT FROM AUTHOR]

Therapsid and other tetrapod fossils from the South African Karoo Supergroup provide the most detailed and best studied terrestrial vertebrate record of the Middle and Late Permian. The resulting biostratigraphic scheme has global applicability. Establishing a temporal framework for these faunas has proven difficult: magnetostratigraphy has been hampered by a Jurassic overprint, and intercorrelation with Permian marine sequences has been equivocal. Here we report U-Pb zircon isotope dilution-thermal ionization mass spectrometry (ID-TIMS) dates for five volcanic ashes interbedded with fossils from the Pristerognathus, Tropidostoma, and Cistecephalus vertebrate biozones of the Beaufort Group. This temporal framework allows correlation to marine zonations and improves understanding of rates of faunal evolution and patterns of basin evolution. Our results identify no correlative vertebrate extinctions in the Karoo Supergroup to the marine end-Guadalupian mass extinction and raise the question of whether there is any record of a terrestrial extinction related to the Emeishan large igneous province. [ABSTRACT FROM AUTHOR]

Comparative developmental studies have revealed a rich array of details about the patterns and processes of morphological change in animals and increasingly in plants. But, applying these insights to the study of major episodes of evolutionary innovation requires understanding how these novel morphologies become established and sufficiently abundant (either as individuals within a species or as a clade of species) to be preserved in the fossil record, and, in many cases, to influence ecological processes. Evolutionary novelties may: (1) disappear without changing the species; (2) be associated with the generation (through selection or drift) of a new species; and if the latter (3) may or may not become ecologically significant. Only the latter are commonly preserved in the fossil record. These alternatives mirror the distinction among historians of technology between innovation and invention. Here, I argue that specific sorts of evolutionary inventions drive ecological transformation, essentially constructing an environment for themselves and ancillary organisms through ecological spillover effects, increasing the 'carrying capacity' of an ecosystem. J. Exp. Zool. (Mol. Dev. Evol.) 318B:460-465, 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A number of developments in the identification and analysis of species were discussed in the 1992 Paleontological Society Symposium. One of these developments was the acknowledgement that only in certain occassions can marine paleontologists reduce time into narrow units to truly see the process of speciation. Another major event was the growing use ofcladistics by paleontologists in their approach to speciation. Lastly, there was a mounting recognition of the importance of the ecological context of evolutionary events.

The article explores a divergence event during the early Cambrian period resulting in the appearance of bilaterian animal species. Scientists have debated influences on this diversification, suggesting environmental, developmental, and ecological factors as possible causes. Studies of the fossil record, along with comparisons of developmental patterning and networks of ecological interactions, indicate that what the authors call a macroevolutionary lag occurred between the divergence of animal clades and their first appearance in the fossil record.

The fossil record of animal life is far more incomplete and patchy than even the most obscure historical records. Consequently, some of the approaches developed by paleobiologists over the past couple of decades to assess the reliability of the fossil record, investigate patterns and infer underlying processes may be useful in analyzing historical data as well. Here I discuss two examples where paleontologists have investigated historical questions, in one case the evolution of cornets, in the second estimating the survival rate of Medieval manuscripts. Depending on the scope of big history, there are a number of areas where history and paleontology overlap, particularly in the investigation of early human history. More rigorous analysis of the biases of the historical record may be of some use in determining which historical patterns are sufficiently reliable for further exploration. [ABSTRACT FROM AUTHOR]

The behavior of organisms can contribute to the transformation of their environments. When organismal impacts on the environment feed back to influence organismal density, viability, fertility, or persistence, the environment can be construed as an extension of the organism. This process of fitness-enhancing environmental transformation has been called niche construction. We focus on the relationship of niche construction with species or strain diversity and on the variability of investment in niche construction versus reproduction. We demonstrate a fundamental dilemma of niche construction, whereby the construction of a shared resource leads to a tragedy of the commons, with competition tending to eliminate niche construction strategies. The ability to monopolize a niche, either through spatial proximity or through preferential exploitation, can stabilize niche construction and promote ecological coexistence among polymorphic constructors. We consider both sympatric and allopatric origins of niche construction. Under a variety of different construction mechanisms, variability in the investment in niche construction versus reproduction suggests reproductive altruism but is fully consistent with selfish behavior. We discuss the implications of niche-construction theory on the evolution of life cycles and development, behavioral plasticity, the division of labor, and long-term macroevolutionary trends. [ABSTRACT FROM AUTHOR]

Current plant and animal diversity preserves at most 1-2% of the species that have existed over the past 600 million years. But understanding the evolutionary impact of these extinctions requires a variety of metrics. The traditional measurement is loss of taxa (species or a higher category) but in the absence of phylogenetic information it is difficult to distinguish the evolutionary depth of different patterns of extinction: the same species loss can encompass very different losses of evolutionary history. Furthermore, both taxic and phylogenetic measures are poor metrics of morphologic disparity. Other measures of lost diversity include: functional diversity, architectural components, behavioral and social repertoires, and developmental strategies. The canonical five mass extinctions of the Phanerozoic reveals the loss of different, albeit sometimes overlapping, aspects of loss of evolutionary history. The end-Permian mass extinction (252 Ma) reduced all measures of diversity. The same was not true of other episodes, differences that may reflect their duration and structure. The construction of biodiversity reflects similarly uneven contributions to each of these metrics. Unraveling these contributions requires greater attention to feedbacks on biodiversity and the temporal variability in their contribution to evolutionary history. Taxic diversity increases after mass extinctions, but the response by other aspects of evolutionary history is less well studied. Earlier views of postextinction biotic recovery as the refilling of empty ecospace fail to capture the dynamics of this diversity increase. [ABSTRACT FROM AUTHOR]

Organisms influence their environments through activities that range from bioturbation to modification of redox gradients and construction of structures. Some of these activities modify the selective regime of the builder (niche construction) and some influence the ecological success of other species (ecosystem engineering) as well as their evolutionary prospects. In this article, I argue that these processes produce effects that persist over geological time, modulating macroevolutionary patterns and diversity. Examples include greater sediment bioturbation and increased thickness and persistence of shell beds. The impact of these processes has been increasing over time, with recent communities encompassing greater ecosystem engineering than those of the early Phanaerozoic. Thus, positive feedback through environmentally mediated selection seems to have increasingly enhanced biodiversity through the Phanaerozoic. [Copyright &y& Elsevier]

The increased application of abundance data embedded within a more detailed and precise environmental context is enabling paleontologists to explore more rigorously the dynamics and underlying processes of ecological and evolutionary change in deep time. Several recent findings are of special theoretical interest. Community membership is commonly more stable and persistent than expected by chance, even in the face of the extreme environmental changes of the Ice Ages, and major evolutionary novelties commonly lie dormant for tens of millions of years before the ecological explosions of the clades that possess them. As we discuss here, questions such as these cannot be adequately addressed without the use of the fossil record. [Copyright &y& Elsevier]

Development of the animal body plan is controlled by large gene regulatory networks (GRNs), and hence evolution of body plans must depend upon change in the architecture of developmental GRNs. However, these networks are composed of diverse components that evolve at different rates and in different ways. Because of the hierarchical organization of developmental GRNs, some kinds of change affect terminal properties of the body plan such as occur in speciation, whereas others affect major aspects of body plan morphology. A notable feature of the paleontological record of animal evolution is the establishment by the Early Cambrian of virtually all phylum-level body plans. We identify a class of GRN component, the "kernels" of the network, which, because of their developmental role and their particular internal structure, are most impervious to change. Conservation of phyletic body plans may have been due to the retention since pre-Cambrian time of GRN kernels, which underlie development of major body parts. [ABSTRACT FROM AUTHOR]

The fossil record preserves numerous natural experiments that can shed light on the response of ecological communities to environmental change. However, directly observing the community dynamics of extinct organisms is not possible. As an alternative, neutral ecological models suggest that species abundance distributions reflect dynamical processes like migration, competition, recruitment, and extinction. Live-dead comparisons suggest that such distributions can be faithfully preserved in the rock record. Here we use a maximum-likelihood approach to show that brachiopod (lamp shell) abundance distributions from four temporally distinct ecological landscapes from the Glass Mountains, Texas (of the Permian period), exhibit significant differences. Further, all four are better fitted by zero-sum multinomial distributions, characteristic of Hubbell's neutral model, than by log-normal distributions, as predicted by the traditional ecological null hypothesis. Using the neutral model as a guide, we suggest that sea level fluctuations spanning about 10?Myr altered the degrees of isolation and exchange among local communities within these ecological landscapes. Neither these long-term environmental changes nor higher-frequency sea level fluctuations resulted in wholesale extinction or major innovation within evolutionary lineages. [ABSTRACT FROM AUTHOR]

Describes an assemblage of silicified microgastropods from the Heshan formations in China. Demonstration of gastropod diversity; Inclusion of the latest family of gastropods; Implications for understanding gastropod extinction patterns.

Analyzes the temporal distribution of silica-replaced fossils and bedded chert to determine the influence of factors such as extinctions and climate change on siliceous facies. Comparison of silica-replaced fossils and bedded cherts at same level; Trends in silica replacement of fossils; Significant sources of variation in the silica cycle.

Discusses the effects of mass extinctions on evolution. Evolutionary opportunities created by mass extinctions; Biotic rebound occurring to refill niches created by mass extinctions; Paleontological discussions of post-extinction recoveries; Case studies presented; Evolutionary significance of post-extinction recoveries.

Understanding the complex patterns of latitudinal diversity gradients (LDGs) in deep time has been hampered by the absence of long-term records of LDGs through multiple climatic changes. We used records of marine invertebrate fossils to generate LDGs in each age bin from the Carboniferous icehouse to the Triassic greenhouse climates. We evaluated LDGs by subsampling, calculated evolutionary rates for different latitudinal zones, and assessed the modularity of the fossil data within latitudinal zones using the Louvain algorithm. Our results suggest that the LDG peaks may be shaped by multiple factors rather than alternating icehouse and greenhouse climates, although icehouse climates usually restrict diversity at high latitudes. In nearly all clades, peak diversity shifted northward during the late Carboniferous and early Permian, reflecting the northward drift of plates and increased habitat area. Changes in the steepness of the LDG was most pronounced at low latitudes and during biotic crises and recovery, while icehouse to greenhouse transitions created more deviation at high latitudes. Our results show a strong historical influence from previous LDG patterns in LDG dynamics, but one that was interrupted by upheavals in composition after dramatic environmental changes. [ABSTRACT FROM AUTHOR]

The distribution of species body size within taxonomic groups exhibits a heavy right tail extending over many orders of magnitude, where most species are much larger than the smallest species. We provide a simple mode of cladogenetic diffusion over evolutionary time that omits exp licit mechanisms for interspecific competition and other microevolutionary processes, yet fully explains the shape of this distribution. We estimate the model's parameters from fossil data and find that it robustly reproduces the distribution of 4002 mammal species from the late Quaternary. The observed fit suggests that the asymmetric distribution arises from a fundamental trade-off between the short-term selective advantages (Cope's rue) and long-term selective risks of increased species body size in the presence of a taxon-specific lower limit on body size. [ABSTRACT FROM AUTHOR]

In his theory of Economic Development, economist Joseph Schumpeter distinguished between inventions — the creation and establishment of something new — and innovations, inventions that become economically successful and earn profits. In this distinction, Schumpeter echoes an earlier dichotomy in biology between the physical sources of genetic and phenotypic variability among organisms and those factors leading to the establishment of a favored variant within a population. Schumpeter's definition of invention intentionally includes fixation, and thereby highlights the elusive nature of innovation with its connotation of influence and success.Case studies of invention and innovation abound, from the Cambrian radiation of animals in biology to the telegraph, telephone, and Internet in technology, and some are sufficiently beguiling to obscure an evident lack of generality.