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Reconstructing past herd mobility, reproduction, and diet is crucial for understanding animal management practices among the first sedentary farming communities. It can also shed light on how domestic animals were integrated into the existing exchange networks of goods, products, and raw materials, and how they contributed to broader economic and social changes during the Neolithic. Despite the longstanding importance of cattle (Bos taurus) to herders, the role of cattle in the daily, seasonal, and annual cycle of activities of early farming communities remains relatively poorly understood. This study focuses on the Middle Neolithic site of Cova de les Pixarelles (3942–3632 cal. BCE) one of the few sites in the Iberian Peninsula from this period with a substantial collection of faunal remains. The site is particularly notable for its high proportion of cattle remains. Previous research on the cattle bone assemblage from Cova de les Pixarelles has included comprehensive archaeozoological, palaeopathological, and biomechanical analyses—an innovative, integrative approach in Mediterranean archaeology that offers an exceptional level of biographical detail. This study uses bulk bone collagen carbon (δ13Ccoll) and nitrogen (δ15N) isotopes, and sequential analysis of enamel bioapatite oxygen (δ18O) and carbon (δ13Ccarb) isotopes to further enhance our understanding of animal management practices during the Middle Neolithic, providing new insights on the diet, mobility and reproduction patterns of cattle. Results indicate that the Neolithic communities that used Cova de les Pixarelles managed these animals to obtain optimal pastures, moving them seasonally from lowland areas to higher mountain plateaus and carefully managing their reproduction cycles. We suggest a nuanced herding approach, combining open-range grazing with an ecological division of herds based on age, sex, and reproductive function, and seasonal vertical mobility, contributing to a complex but efficient herding system during the Middle Neolithic. [ABSTRACT FROM AUTHOR]

The volume of human carbon (δ13C) and nitrogen (δ15N) isotope data produced in archaeological research has increased markedly in recent years. However, knowledge of bone remodelling, its impact on isotope variation, and the temporal resolution of isotope data remains poorly understood. Varied remodelling rates mean different elements (e.g., femur and rib) produce different temporal signals but little research has examined intra-element variability. This study investigates human bone remodelling using osteon population density and the relationship with carbon and nitrogen isotope data at a high resolution, focusing on variation through femoral cross-sections, from periosteal to endosteal surfaces. Results demonstrate considerable differences in isotope values between cross-sectional segments of a single fragment, by up to 1.3‰ for carbon and 1.8‰ for nitrogen, illustrating the need for standardised sampling strategies. Remodelling also varies between bone sections, occurring predominantly within the endosteal portion, followed by the midcortical and periosteal. Therefore, the endosteal portion likely reflects a shorter period of life closer to the time of death, consistent with expectations. By contrast, the periosteal surface provides a longer average, though there were exceptions to this. Results revealed a weak negative correlation between osteon population density and δ15N or δ13C, confirming that remodelling has an effect on isotope values but is not the principal driver. However, a consistent elevation of δ15N and δ13C (0.5‰ average) was found between the endosteal and periosteal regions, which requires further investigation. These findings suggest that, with further research, there is potential for single bone fragments to reconstruct in-life dietary change and mobility, thus reducing destructive sampling. [ABSTRACT FROM AUTHOR]

The δ13C composition of Cibicidoides wuellerstorfi and other Cibicidoides spp is an important tool to reconstruct past changes in the deep ocean carbon cycle. The species are expected to match the δ13C of ambient dissolved inorganic carbon (DIC), although it has been recognized that substantial offsets can occur. Here, I present a compilation of modern δ13C and δ18O data for named Cibicidoides species in combination with fully resolved carbonate chemistry at each core location. The data show for C. wuellerstorfi that the offset from the expected value in both carbon (∆13C) and oxygen (∆18O) is correlated with seawater carbonate chemistry. The result is comparable to, but not identical with, published culture experiments in which marine organisms were grown under variable pH‐conditions. Overall, ∆13C in C. wuellerstorfi correlates positively with carbonate saturation, [DIC], and temperature. The three variables together explain 47.1% of the variation in ∆13C. The trend for ∆18O is similar, except that the effect of temperature has been removed through correction with a published δ18O‐temperature equation. Up to 35% of the remaining variation in ∆18O can be explained by ambient carbonate chemistry. Data for other named Cibicidoides species are broadly similar, but are too sparse for a detailed analysis. The results indicate that strongly negative ∆13C occurs predominantly in the deep Atlantic in response to a combination of low [DIC], low temperature, and undersaturation within the lysocline. Implications for paleoceanographic reconstructions are discussed. Key Points: The offset between the measured and expected δ13C and δ18O of Cibicidoides wuellerstorfi correlates with seawater carbonate chemistryNegative ∆13C occurs mainly in the deep Atlantic due to a combination of low temperature, under‐saturation, and low to intermediate dissolved inorganic carbon [ABSTRACT FROM AUTHOR]

The paleoceanographic history of the Pacific Ocean during the mid-Cretaceous is poorly constrained due to the loss of much of the contemporaneous Pacific seafloor to subduction and difficulties in recovering chert-rich sediments by ocean drilling. Pelagic sediments that were originally deposited in the Pacific Ocean but that have been subsequently accreted during subduction potentially provide an alternative paleoceanographic archive. This study presents micropaleontological and carbon-isotope data from the Calera Limestone, part of the classic Franciscan Complex exposed in Permanente Quarry, central California, USA. In the three stratigraphic sections studied, pelagic limestones with low organic-carbon contents are the dominant lithology. However, two stratigraphic intervals are recognized that contain organic carbon, and these date to the early Aptian and late Albian--early Cenomanian. These time intervals correspond to two mid-Cretaceous oceanic anoxic events (OAEs): early Aptian OAE1a (equivalent to the 'Selli level') and late Albian OAE1d (equivalent to the 'Breistroffer event'). It is well established that both of these events were associated with significant carbon-isotope excursions, which are also shown to exist in the Calera Limestone. The record of OAE1a from the Calera Limestone complements ocean drilling records by providing further evidence for variability in the sedimentary and stratigraphic record of this event. The carbon-isotope data from the late Albian--early Cenomanian provide the first detailed chemobiostratigraphic record of this period for the Pacific Ocean, confirming that environmental change occurred at this time in the Pacific, possibly related to OAE1d. Keywords: Cretaceous, oceanic anoxic events, carbon isotopes, Calera Limestone, paleoceanography.

A two-box ocean model with a coupled carbon and phosphorus cycle is used to test which processes can realistically generate a rapid positive 2[per thousand] [[delta].sup.13]C excursion in the global carbon reservoir, Internal oceanic processes (enhanced preservation of organic matter under anoxic conditions, enhanced upwelling) cannot produce a substantial [[delta].sup.13]C excursion under the assumption that burial rates of C and P are coupled. Loss of nutrients to the sediment acts as a negative feedback mechanism that prevents a substantial perturbation of the carbon cycle. A large and renewable source of nutrients is needed, either from increased continental weathering or from enhanced regeneration of sedimentary organic phosphorus under anoxic conditions. Measurements of total phosphorus and organic carbon in sediments from the Tarfaya Basin, Morocco, suggest that a large decrease in P burial occurred relative to organic carbon at the base of the Cenomanian--Turonian Oceanic Anoxic Event (OAE2), with the right magnitude to quantitatively explain a 2[per thousand] shift in [[delta].sup.13]C. It is concluded that the main underlying mechanism that allowed and sustained enhanced carbon burial during the mid-Cretaceous was a perturbation of the oceanic phosphorus cycle. Keywords: Cenomanian, OAE2, carbon cycle, phosphorus.

At Ocean Drilling Program Site 689 (Maud Rise, Southern Ocean), [[Delta].sup.18]O records of fine-fraction bulk carbonate and benthic foraminifers indicate that accelerated climate cooling took place following at least two closely spaced early late Eocene extraterrestrial impact events. A simultaneous surface-water productivity increase, as interpreted from [[Delta].sup.13]C data, is explained by enhanced water-column mixing due to increased latitudinal temperature gradients. These isotope data appear to be in concert with organic-walled dinoflagellate-cyst records across the same microkrystite-bearing impact-ejecta layer in the mid-latitude Massignano section (central Italy). In particular, the strong abundance increase of Thalassiphora pelagica is interpreted to indicate cooling or increased productivity at Massignano. Because impact-induced cooling processes are active on time scales of a few years at most, the estimated 100 k.y. duration of the cooling event appears to be too long to be explained by impact scenarios alone. This implies that a feedback mechanism, such as a global albedo increase due to extended snow and ice cover, may have sustained impact-induced cooling for a longer time after the impacts. Keywords: Eocene, meteorites, climate effects, ODP Site 689.

We present preliminary sclerochronological analysis on 15 Argyrosomus regius (meagre) otoliths collected from two different human occupation levels from the Cabeço da Amoreira shell midden (Muge valley, Portugal). The otoliths were sectioned and observed under a reflected light stereomicroscope to examine seasonal growth rings. Carbonates collected from individual growth rings subsampled with a micromill sampling device were analyzed for their stable oxygen isotope content with the objective of determining the predominant season of capture and therefore season of site use, environmental conditions, and sites of resource procurement (local versus regional). The otoliths' stable isotope records show clear seasonality and a season of capture estimate that seems consistent with a "good season" (warmer season, i.e., from spring to late summer/beginning of autumn in this area) site use in the last occupation layer (the great majority of otoliths are from layer 1), except for four samples giving heaver oxygen isotope (δ18O) values that suggest colder conditions and only one with markedly positive δ18O values. Potential effect of diagenesis on the otolith records was also assessed through coupled laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) and by micro-X-Ray diffraction (μ-XRD). Results revealed the presence of only aragonite and no traces of calcite, providing no evidence of diagenesis that could significantly alter isotope results and lead to erroneous interpretations. The implications of these results are discussed and compared with data from other archeological sites, as well as data from micromorphology regarding continuity or interruption of site use and other faunal remains. [ABSTRACT FROM AUTHOR]