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Redescription of Early Pennsylvanian trace-fossil holotypes from the nonmarine Hindostan Whetstone beds of Indiana
- Christopher G. Maples, Allen W. Archer
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- Journal:
- Journal of Paleontology / Volume 61 / Issue 5 / September 1987
- Published online by Cambridge University Press:
- 14 July 2015, pp. 890-897
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The late Namurian Hindostan Whetstone beds are among the oldest Pennsylvanian strata recognized in the Illinois Basin. Trace-fossil holotypes of Haplotichnus indianensis, Plangtichnus erraticus, and Treptichnus bifurcus were first described and illustrated from these nonmarine strata with line drawings without reference to scale in a relatively obscure work by S. A. Miller (1889). These holotypes are refigured and redescribed in this paper. Based on examination of holotype collections, the Ordovician “Feather-stitch Trail” of Wilson (1948) is judged not to be congeneric with Treptichnus. The ichnogenus Ancorichnus, which is present in the Hindostan Whetstone beds, superficially resembles Haplotichnus; however, Haplotichnus lacks the internal meniscae characteristic of Ancorichnus.
The case for strategic international alliances to harness nutritional genomics for public and personal health†
- Jim Kaput, Jose M. Ordovas, Lynnette Ferguson, Ben van Ommen, Raymond L. Rodriguez, Lindsay Allen, Bruce N. Ames, Kevin Dawson, Bruce German, Ronald Krauss, Wasyl Malyj, Michael C. Archer, Stephen Barnes, Amelia Bartholomew, Ruth Birk, Peter van Bladeren, Kent J. Bradford, Kenneth H. Brown, Rosane Caetano, David Castle, Ruth Chadwick, Stephen Clarke, Karine Clément, Craig A. Cooney, Dolores Corella, Ivana Beatrice Manica da Cruz, Hannelore Daniel, Troy Duster, Sven O. E. Ebbesson, Ruan Elliott, Susan Fairweather-Tait, Jim Felton, Michael Fenech, John W. Finley, Nancy Fogg-Johnson, Rosalynn Gill-Garrison, Michael J. Gibney, Peter J. Gillies, Jan-Ake Gustafsson, John L. Hartman IV, Lin He, Jae-Kwan Hwang, Jean-Philippe Jais, Yangsoo Jang, Hans Joost, Claudine Junien, Mitchell Kanter, Warren A. Kibbe, Berthold Koletzko, Bruce R. Korf, Kenneth Kornman, David W. Krempin, Dominique Langin, Denis R. Lauren, Jong Ho Lee, Gilbert A. Leveille, Su-Ju Lin, John Mathers, Michael Mayne, Warren McNabb, John A. Milner, Peter Morgan, Michael Muller, Yuri Nikolsky, Frans van der Ouderaa, Taesun Park, Norma Pensel, Francisco Perez-Jimenez, Kaisa Poutanen, Matthew Roberts, Wim H.M. Saris, Gertrud Schuster, Andrew N. Shelling, Artemis P. Simopoulos, Sue Southon, E. Shyong Tai, Bradford Towne, Paul Trayhurn, Ricardo Uauy, Willard J. Visek, Craig Warden, Rick Weiss, John Wiencke, Jack Winkler, George L. Wolff, Xi Zhao-Wilson, Jean-Daniel Zucker
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- Journal:
- British Journal of Nutrition / Volume 94 / Issue 5 / November 2005
- Published online by Cambridge University Press:
- 08 March 2007, pp. 623-632
- Print publication:
- November 2005
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Nutrigenomics is the study of how constituents of the diet interact with genes, and their products, to alter phenotype and, conversely, how genes and their products metabolise these constituents into nutrients, antinutrients, and bioactive compounds. Results from molecular and genetic epidemiological studies indicate that dietary unbalance can alter gene–nutrient interactions in ways that increase the risk of developing chronic disease. The interplay of human genetic variation and environmental factors will make identifying causative genes and nutrients a formidable, but not intractable, challenge. We provide specific recommendations for how to best meet this challenge and discuss the need for new methodologies and the use of comprehensive analyses of nutrient–genotype interactions involving large and diverse populations. The objective of the present paper is to stimulate discourse and collaboration among nutrigenomic researchers and stakeholders, a process that will lead to an increase in global health and wellness by reducing health disparities in developed and developing countries.
An estuarine model for Pennsylvanian Lagerstätten
- Howard R. Feldman, Christopher G. Maples, Allen W. Archer, Ronald R. West, Erik P. Kvale
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- Journal:
- The Paleontological Society Special Publications / Volume 6 / 1992
- Published online by Cambridge University Press:
- 26 July 2017, p. 95
- Print publication:
- 1992
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Estuaries were important sites of deposition throughout most of the Pennsylvanian in the Midcontinent. Modern estuaries typically occur within flooded river valleys where marine and fresh waters mix. Characteristic estuarine circulation results in locally high rates of deposition of muddy sediment that can lead to good preservation of fossils. Several Pennsylvanian conservat-Lagerstätten are best interpreted as having formed within ancient estuaries. Three types of estuarine deposits have been identified. Type 1 estuarine systems are large-scale transgressive systems that start with fluvial sands overlying an erosional surface. This is overlain successively by middle-estuarine laminated mudstone, and finally marine mudstone and shale. Well-preserved fossils occur in laminated mudstones and siltstones. This sequence may include within in it type 3 estuarine Lagerstätten. An example is the Douglas Group (Missourian, Kansas).
Type 2 estuarine Lagerstätten consist of thin estuarine deposits confined to narrow paleochannels. This includes the Garnett (Missourian, Kansas) and Hamilton (Virgilian, Kansas) deposits, both of which contain articulated vertebrates and well-preserved plants. Both channels are filled with mixed siliciclastic and carbonate sediments. Fine grained facies from which the best fossils are recovered in both contain evidence of tidal deposition, although tidal rhythmicity is best developed in the Hamilton channel. Plant assemblages in both are dominated by the conifer Walchia, probably indicating a relatively dry climate.
Type 3 estuarine Lagerstätten consist of thick gray-shale wedges that overlie coals. The best-known example is the Francis Creek Shale (Desmoinesian, Illinois). A relatively wet climate is indicated by abundant fern and seed-fern foliage. Laminations in shale facies commonly show well-developed tidal rhythmicity. A typical stratigraphic succession starts with laminated shale overlying coal. This grades upwards into flaser and lenticular bedding to ripple and then large-scale cross-bedded sandstone. Upright trees rooted in the coal indicate rapid burial. Well-preserved fossils are recovered from early-diagenetic siderite concretions from the laminated shale.
Preservation of fossils is best in laminated mudstones deposited in middle-estuarine environments where conditions are ideal for good preservation. In all cases so far studied the zones of best preservation are well laminated and have sparse (if any) burrows and sessile benthic fossils. Most of the well-preserved organisms are terrestrial, nektonic, or at least mobile. Brackish and fluctuating salinities restricted scavenging and burrowing organisms that may scatter skeletons. High turbidity and deposition rate may have further discouraged many organisms. Matching bedding rhythmicity with tidal cycles allows calculation of depositional rates of 1 cm or more of compacted sediment per 2-week neap-spring tidal cycle. This is consistent with the high rates of deposition known from modern tidal environments. High depositional rates assured that any organism that fell to the sea floor was buried in a few hours to a few days. Once buried anoxic conditions established around decaying carcasses may have led to early mineralization.
Pliocene scallop growth lines: potential for environmental reconstruction and population dynamics
- George R. Clark II, Allen W. Archer
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- Journal:
- The Paleontological Society Special Publications / Volume 6 / 1992
- Published online by Cambridge University Press:
- 26 July 2017, p. 58
- Print publication:
- 1992
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Prominent growth ridges on the shell of the modern scallop Pecten diegensis are known to form with a daily periodicity. Pecten stearnsii, its direct ancestor, has the same growth ridges and would be expected to form them at the same rate.
Pecten stearnsii specimens collected from the Pliocene Imperial Formation near San Filipe, Baja California, Mexico, have repetitive variations in the spacing of their growth ridges. Harmonic analysis of these variations found three tidal periodicities to be present, tropic (13.7 days), synodic (14.8 days), and anomalistic (27.6 days). This observation also served to confirm the daily nature of the growth ridges.
Tidal patterns at various locations within the present-day Gulf of California are dominated to various degrees by synodic and tropic periodicities. Comparisons of the growth-line records to modern tidal records by cross-correlation found a good match with a tidal station south of the collecting site, where the tropic periodicity dominates but the synodic periodicity is still important.
An important aspect of this match is that a graph of cross-correlations at all possible overlaps shows a cycle of good correlations, with a period of six months between peaks. As this is a reflection of the resonance between tropic and synodic periodicities, the peaks would occur at the same times of year in the Pliocene as today. This makes it possible to relate each specimen's growth record to the calendar, although two alternate interpretations, six months apart, would exist.
Two possible relationships would be of interest. First, if all the specimens had died at the same time of year it could mean a catastrophe, such as a severe storm. This was not the case, which is in itself a useful observation. Second, if all the specimens began their growth line record at the same time of year, it would suggest specific seasons for spawning and for spatfall. Here the evidence was more supportive; most specimens began forming growth ridges in either late March or late September, with perhaps a month's growth prior to the first growth ridge.
If isotopic paleotemperature analysis can be applied to these shells, or to others with similar characteristics, new levels of resolution in both environmental reconstruction and paleopopulation analysis may be achieved.