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Whether eustatic sea-level rise through the Holocene has been punctuated or continuous has remained controversial for almost two decades. Resolving this debate has implications for predicting future responses of remaining ice sheets to climate change and also for understanding the drivers of human settlement and dispersal patterns through prehistory. Here we present a sea-level curve for the past 8900 yr from Singapore, a tectonically stable location remote from ice-loading effects. We also present critical and unique sedimentation rate, organic [delta][sup.13]C, and foraminiferal [delta][sup.13]C proxy records of sea-level change derived from a shallow-marine sediment core from the same area over the same time interval. The sea-level curve, corroborated by the independent proxy records, suggests rapid rise at a rate of 1.8 m/100 yr until 8100 cal (calibrated) yr B.P., a near cessation in the rate of sea-level rise between 7800 and 7400 cal yr B.P., followed by a renewed rise of 4-5 m that was complete by 6500 cal yr B.P. We suggest that this period of relatively stable sea level during the early to mid-Holocene enabled modern deltas to advance, providing a highly productive environment for the establishment of coastal sedentary agriculture. Periods of rapid sea-level rise before and after may have catalyzed significant postglacial episodes of human dispersal in coastal regions. doi: 10.1130/G31066.1

We inferred climate change through the Pleistocene-Holocene transition from [[delta].sup.13]C and [delta]D values of bat guano deposited from 14.5 to 6.5 ka (calendar ka) in Bat Cave, Grand Canyon, Arizona. The [[delta].sup.13]C and [delta]D values generally covaried, indicating that regional late Pleistocene climate was relatively cool and wet, and early Holocene climate gradually became warmer with increased summer precipitation until ca. 9 ka, at which time the onset of modern North American Monsoon-like conditions occurred. During the Younger Dryas event, [[delta].sup.13]C values decreased, whereas [delta]D values increased, indicating a cool and possibly drier period. We also observed a distinct isotopic anomaly during the 8.2 ka event, at which time both [[delta].sup.13]C and [delta]D values decreased. The [[delta].sup.13]C values abruptly increased at 8.0 ka, suggesting a rapid change in atmospheric circulation and greater influence from convective storms originating from the south. Deposits of bat guano represent a largely untapped source of paleoenvironmental information that can provide continuous and long-term continental archives of environmental change. Keywords: arid, precipitation, vegetation, paleoclimate, North American Monsoon.

We generated 10 high-resolution profiles of stable carbon and oxygen isotope values ([delta][sup.13][C.sub.oto] and [delta][sup.13][O.sub.oto]) of sagittal otoliths of whitefish (Coregonus lavaretus) from Lake Annecy (France) to determine the factors that control intra-individual [delta][sup.13][C.sub.oto] variation. Dominant patterns of intra-otolith variation compared well with seasonal and age-specific respiration modeling. Conversely, intra-otolith variation of S C values did not compare well with measured dietary and environmental variation. We infer that the proportion Of metabolically sourced carbon (M) is the dominant control on intra-otolith variation. Current models of otolith carbon incorporation provide different estimates of M. Once appropriate fractionation factors among otolith, endolymph, blood, and carbon sources are elucidated, [delta][sup.13][C.sub.oto] values will reveal energetic, environmental, and dietary information of teleost fish for past and present populations. Used in conjunction with [delta][sup.18][O.sub.oto] values, [delta][sup.13][C.sub.oto] values will be powerful proxies of fish environment, behavior, and evolution. Nous avons etabli les profils des teneurs en isotopes stables du carbone et de l'oxygene ([delta][sup.13][C.sub.oto] et [delta][sup.18][O.sub.oto]) de 10 otolithes sagittales de coregones (Coregonus lavaretus) provenant du lac d'Annecy (France) afin de determiner les facleurs qui controlem les variations intra-individuelles du [delta][sup.13][C.sub.oto]. Les variations inira- otolilhaires des valeurs de [delta][sup.13]C presenieni des caracieristiques sitnilaires aux variations saisonnieres et ontogeniques de l'activite respiratoire reconstruites par un modele de bioenergetique. Au contraire, les variations isoiopiques inira-otolilhaires ne sonl pas semblables aux variations isotopiques mesurees dans F alimentation et F environ nenien t aquatique des coregones. Nous en deduisons que la proportion de carbone derivant de la source inetabolique (M) est le factetir de controle principal des variations intra-otolithaires. Les modeles actueis decrivant l'incorporation du carbone otolithaire ont fourni differentes estimations de M. Une fois que les facteurs de fraction neme nt entre l'otolithe, l'endolymphe, le sang et les sources de carbone seront connus, les mesures de [delta][sup.13][C.sub.oto] devraient permettre de reconstruire l'histoire energetique, environnementale et alimentaire des populations de teleosteens actuelles et passees. Utilisees conjointement aux valeurs de [delta][sup.18][O.sub.oto], les valeurs de [delta][sup.13][O.sub.oto] devraient se reveler de precieux indicateurs de l'environnement, du comportemenl et de revolution des poissons., Introduction Otoliths are accretionary carbonate structures located in the inner ear of fish. Saggitae are the largest of three pairs of otoliths and are composed of aragonite deposited on a [...]

Northern Australia is a region where limited information exists on environments at the last glacial maximum (LGM). Girraween Lagoon is located on the central northern coast of Australia and is a site representative of regional tropical savanna woodlands. Girraween Lagoon remained a perennial waterbody throughout the LGM, and as a result retains a complete proxy record of last-glacial climate, vegetation and fire. This study combines independent palynological and geochemical analyses to demonstrate a dramatic reduction in both tree cover and woody richness, and an expansion of grassland, relative to current vegetation at the site. The process of tree decline was primarily controlled by the cool-dry glacial climate and CO2 effects, though more localised site characteristics restricted wetland-associated vegetation. Fire processes played less of a role in determining vegetation than during the Holocene and modern day, with reduced fire activity consistent with significantly lower biomass available to burn. Girraween Lagoon's unique and detailed palaeoecological record provides the opportunity to explore and assess modelling studies of vegetation distribution during the LGM, particularly where a number of different global vegetation and/or climate simulations are inconsistent for northern Australia, and at a range of resolutions. [ABSTRACT FROM AUTHOR]