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Macroids and rhodoliths, made by encrusting acervulinid foraminifera and coralline algae, are widely recognized as bioengineers providing relatively stable microhabitats and increasing biodiversity for other species. Macroid and rhodolith beds occur in different depositional settings at various localities and bathymetries worldwide. Six case studies of macroid/rhodolith beds from 0 to 117 m water depth in the Pacific Ocean (northern Central Ryukyu Islands, French Polynesia), eastern Australia (Fraser Island, One Tree Reef, Lizard Island), and the Mediterranean Sea (southeastern Spain) show that nodules in the beds are perforated by small-sized boring bivalve traces (Gastrochaenolites). On average, boring bivalve shells (gastrochaenids and mytilids) are more slender and smaller than those living inside shallow-water rocky substrates. In the Pacific, Gastrochaena cuneiformis, Gastrochaena sp., Leiosolenus malaccanus, L. mucronatus, L. spp., and Lithophaga/Leiosolenus sp., for the first time identified below 20 m water depth, occur as juvenile forms along with rare small-sized adults. In deep-water macroids and rhodoliths the boring bivalves are larger than the shallower counterparts in which growth of juveniles is probably restrained by higher overturn rates of host nodules. In general, most boring bivalves are juveniles that grew faster than the acervulinid foraminiferal and coralline red algal hosts and rarely reached the adult stage. As a consequence of phenotypic plasticity, small-sized adults with slow growth rates coexist with juveniles. Below wave base macroids and rhodoliths had the highest amounts of bioerosion, mainly produced by sponges and polychaete worms. These modern observations provide bases for paleobiological inferences in fossil occurrences. [Figure not available: see fulltext.]

Coral reefs are now subject to global threats and influences from numerous anthropogenic sources. Foraminifera, a group of unicellular shelled organisms, are excellent indicators of water quality and reef health. Thus we studied a set of samples taken in 1992 to provide a foraminiferal baseline for future studies of environmental change. Our study provides the first island-wide analysis of shallow benthic foraminifera from around Moorea (Society Archipelago). We analyzed the composition, species richness, patterns of distribution and abundance of unstained foraminiferal assemblages from bays, fringing reefs, nearshore and back- and fore-reef environments. A total of 380 taxa of foraminifera were recorded, a number that almost doubles previous species counts. Spatial patterns of foraminiferal assemblages are characterized by numerical abundances of individual taxa, cluster groups and gradients of species richness, as documented by cluster, Fisher α, ternary plot and Principal Component Analyses (PCA). The inner bay inlets are dominated by stress-tolerant, mostly thin-shelled taxa of Bolivina, Bolivinella, Nonionoides, Elongobula, and Ammonia preferring low-oxygen and/or nutrient-rich habitats influenced by coastal factors such as fresh-water runoff and overhanging mangroves. The larger symbiont-bearing foraminifera (Borelis, Amphistegina, Heterostegina, Peneroplis) generally live in the oligotrophic, well-lit back- and fore-reef environments. Amphisteginids and peneroplids were among the few taxa found in the bay environments, probably due to their preferences for phytal substrates and tolerance to moderate levels of eutrophication. The fringing reef environments along the outer bay are characterized by Borelis schlumbergeri, Heterostegina depressa, Textularia spp. and various miliolids which represent a hotspot of diversity within the complex reef-lagoon system of Moorea. The high foraminiferal Fisher α and species richness diversity in outer bay fringing reefs is consistent with the disturbance-mosaic (microhabitat heterogeneity) hypothesis. Calculations of the FORAM Index (FI), a single metric index to assess reef vitality, indicate that all fore- and most back-reef environments support active carbonate accretion and provide habitat suitability for carbonate producers dependent on algal symbiosis. Lowest suitability values were recorded within the innermost bays, an area where natural and increasing anthropogenic influences continue to impact the reefs. The presence of habitat specific assemblages and numerical abundance values of individual taxa show that benthic foraminifera are excellent recorders of environmental perturbations and good indicators useful in modern and ancient ecological and environmental studies.

• Chapter 1. PaleoParks: Our paleontological heritage protected and conserved in the field worldwide, by Jere H. Lipps, p. 1-10, 20 figs. • Chapter 2. The Triassic Guanling fossil Group - A key GeoPark from Barren Mountain, Guizhou Province, China, by Xiaofeng Wang, Xiaohong Chen, Chuanshang Wang & Long Cheng, p. 11-28, 30 figs., 2 tables. • Chapter 3. The GeoPark of Haute-Provence, France - Geology and palaeontology protected for sustainable development, by Jean-Simon Pagès, p. 29-34, 11 figs. • Chapter 4. The protection and use of the geological and paleontological heritage in Baja California Sur, Mexico, by Javier Gaitán Morán & Alejandro Álvarez Arellano • Capítulo 4. El resguardo y aprovechamiento del patrimonio geológico y paleontológico en Baja California Sur, México, por Javier Gaitán Morán & Alejandro Álvarez Arellano, p. 35-48, 4 figs. • Chapter 5. Protecting fossil sites in New Zealand, by Bruce W. Hayward, p. 49-64, 10 figs., 6 tables. • Chapter 6. The Salt Range: Pakistan's unique field museum of geology and paleontology, by Shahid Jamil Sameeni, p. 65-73, 28 figs. • Chapter 7. Paleontological parks and museums and prominent fossil sites in Thailand and their importance in the conservation of fossils, by Nareerat Boonchai, Paul J. Grote & Pratueng Jintasakul, p. 75-95, 13 figs. • Chapter 8. Managing fossil resources at the Falls of the Ohio, Indiana and Kentucky, USA: A fossil park in an urban setting, by Alan Goldstein, p. 97-101, 8 figs., 1 table. • Chapter 9. Paleo-piracy endangers Vendian (Ediacaran) fossils in the White Sea - Arkhangelsk region of Russia, by Mikhail A. Fedonkin, Andrey Yu. Ivantsov, Maxim V. Leonov, Jere H. Lipps, Ekaterina A. Serezhnikova, Eugeniy I. Malyutin & Yuriy V. Khan, p. 103-111, 12 figs. • Chapter 10. Copper Canyon track locality (Pliocene) conservation strategies, Death Valley National Park, USA, by Torrey Nyborg, p. 113-119, 4 figs. • Chapter 11. A possible Late Miocene fossil forest PaleoPark in Hungary, by Géza Császár, Miklós Kázmér, Boglárka Erdei & Imre Magyar, p. 121-133, 19 figs.

Bonebeds are vertebrate bioclast concentrations in beds that are local to basinal in extent. The middle Miocene Sharktooth Hill bonebed in the southeastern San Joaquin Basin of California is among the largest of such deposits, exposed over 15 km and containing a rich assemblage of marine vertebrates, with a mean density of ~200 specimens/[m.sup.2]. It ranks among the most widespread and richest bonebeds known, yet its genesis is poorly understood. Hypotheses for its origin and formation include mass death from shark predation, volcanic or red tide poisoning, accumulation from a calving ground for marine mammals, and condensed accumulation over a long period of time. Based on multiple kinds of evidence, we conclude that the bonebed formed over a protracted time interval of little to no net clastic sedimentation, coincident with a significant transgressive-regressive cycle between 16 and 15 Ma ago, during the middle Miocene Climatic Optimum (MMCO). Geochronological constraints bracket the duration of bonebed formation to no longer than 700 ka, indicating that time averaging is a critical consideration for paleoecological analyses of North Pacific Ocean biotic richness during the MMCO.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2005.04.010 Byline: Jere H. Lipps (a)(b), Sarah Rieboldt (a)(b) Keywords: Europa; Astrobiology; Habitats; Taphonomy; Exploration Abstract: Jupiter's moon Europa possesses an icy shell kilometers thick that may overlie a briny ocean. The inferred presence of water, tidal and volcanic energy, and nutrients suggests that Europa is potentially inhabited by some kind of life; indeed Europa is a primary target in the search for life in the Solar System although no evidence yet exists for any kind of life. The thickness of the icy crust would impose limits on life, but at least 15 broad kinds of habitats seem possible for Europa. They include several on the sea floor, at least 3 in the water column, and many in the ice itself. All of these habitats are in, or could be transported to, the icy shell where they could be exposed by geologic activity or impacts so they might be explored from the surface or orbit by future planetary missions. Taphonomic processes that transport, preserve, and expose habitats include buoyant ice removing bottom habitats and sediment to the underside of the ice, water currents depositing components of water column habitats on the ice bottom, cryovolcanoes depositing water on the surface, tidal pumping bringing water column and ice habitats to the near-surface ice, and subice freezing and diapiric action incorporating water column and bottom ice habitats into the lower parts of the icy shell. The preserved habitats could be exposed at or near the surface of Europa chiefly in newly-formed ice, tilted or rotated ice blocks, ridge debris, surface deposits, fault scarps, the sides of domes and pits, and impact craters and ejecta. Future exploration of Europa for life must consider careful targeting of sites where habitats are most likely preserved or exist close to the surface. Author Affiliation: (a) Department of Integrative Biology, 3140, 3060 VLSB, University of California, Berkeley, CA 94720, USA (b) Museum of Paleontology, University of California, Berkeley, CA 94720, USA Article History: Received 17 August 2004; Revised 29 March 2005

Megathrust earthquakes in western North America may be preceded by a precursor phase several years prior to megathrust, induced earthquakes. For example, on 27 March 1964, a 9.2 magnitude (on the Richter scale) earthquake occurred on the coast of Alaska. Changes in foraminifera and diatom assemblages at Girdwood Flats, Alaska, provide evidence of a precursor to this earthquake, thereby detailing a previously unknown sequence of events. We describe further evidence of precursor phases from marshes in Turnagain Arm, Alaska, United States, and farther south in Netarts Bay, Oregon, United States; this is the first time that two widely spaced locations have been examined for earthquake-related precursor stages. The Alaska earthquake offers the possibility to compare a modern sequence (A.D. 1964) of events with the geologic record. The Netarts Bay marsh has experienced no modern earthquake that could be used for comparison, but the nature of megathrust zones implies that the modern and ancient events should be physically similar. New cores examined from Turnagain Arm include both the 1964 earthquake and an event identified and dated at 1800 yr B.P. Prior to the 1964 event, the foraminifera and thecamoebian assemblages changed from a forest phase to a mildly brackish stage; this sequence was dated as being 15 yr or less in length, using [Pb.sup.210] and [Cs.sup.137] dating techniques. The event at 1800 yr B.P. was also associated with a similar precursor stage, indicating a small subsidence prior to the megathrust earthquake-related subsidence event. In Netarts Bay a new core was taken at a previously cored site to make use of carbon-14 dates and the assurance that at least four events were known to have occurred over the past 3000 yr. The new core contains four transitions, each identified by a mineralic deposit, often sharply bounded below and gradationally overlain by marsh peat. Transition in this context refers to the section of core analyzed, ~15 cm above and below each of the four sand layers. Foraminiferal assemblage analyses indicate that these units represented a high marsh prequake phase followed by a lower marsh precursor stage, the earthquake-related deposition (sand layer), and then a rebound back into postquake marsh deposits. Sand deposits with either no or few foraminifera are inferred as tsunami/ earthquake-related deposition stages. These transitions in two widely separated geographic areas (Alaska and Oregon) indicate that similar mechanisms operate for large megathrust earthquakes at subduction zones from Alaska to northern California in the Cascadia Subduction Zone, thus implying that precursor events also occur and can be detected by foraminiferai zonation all along this area. In a recent article (Dragert et al., 2001), scientists from the west coast suggested that 'slow' or 'silent' earthquakes they measured with continuous geographical positioning systems might be indicators of megathrust earthquakes. The transitions we document may be the prehistoric representations of these 'silent' quakes. Foraminiferal evidence may help by allowing, more accurate positioning of seismometers along the west coast of North America and thereby lead to more precise and timely earthquake prediction methods. Keywords: precursor, megathrust earthquake, foraminifera, thecamoebian, marsh/ forest transition.