Fluvial and maritime drainage installations with roman amphorae: the Flavian wharf at Caño de Sancti petri (San Fernando, Cádiz)

En este trabajo se presentan los resultados del estudio e interpretación de una excavación de urgencia que tuvo lugar a principios de 1996 en la salina de San Cayetano en San Fernando (Cádiz), junto a una de las orillas del Caño de Sancti Petri. La estructura localizada se componía de una serie de alineaciones paralelas de ánforas romanas machihembradas, en posición horizontal, situadas en dos niveles y reforzadas entre sí por pilotes de madera de pino (datados por C-14), sobre las cuales se localizaron los restos de una pavimentación pétrea. El conjunto parece fecharse en época flavia a tenor de las precisiones derivadas del estudio de los envases ánforicos reutilizados, que ascienden a más de cuarenta (mayoritariamente salsarias béticas altoimperiales –Dr. 7/11, Beltrán II A y Beltrán II B–, olearias del Valle del Guadalquivir –Dr. 20– y otros tipos importados –Dr. 2/4 y Dr. 14–). Los paralelos edilicios localizados, especialmente en la zona noritálica (laguna de Venecia y llanura padana) y en la desembocadura del Ródano permiten relacionar esta estructura con los restos de una plataforma drenante hidrófuga destinada a garantizar la solidez y horizontalidad del substrato. Su localización en la orilla del Caño de Sancti Petri, unida al actual topónimo (Los Cargaderos) y a su relación con las villae altoimperiales situadas en las inmediaciones permiten interpretar este yacimiento como un posible embarcadero destinado a facilitar el tránsito de mercancías en esta zona del archipiélago gaditano. Al hilo de este hallazgo se plantean algunas reflexiones sobre las construcciones realizadas con ánforas en el ámbito de la isla de San Fernando (como reflejo de la problemática general de la Bahía de Cádiz) y especialmente sobre el uso de madera en las instalaciones portuarias hispanorromanas.We present in this paper the results of the archaeological study of a rescue excavation carried out in 1996 in the so called “Salina de San Cayetano” in the city of San Fernando (Cádiz), near one of the banks of the “Caño de Sancti Petri”. The structure is composed of two levels of interconnected amphorae located in parallel horizontal lines, reinforced by pine stakes, underneath a small stones pavement. The site is dated in flavian times according to the information provided by the more than forty reused vessels (mainly baetican amphorae for fish –Dr. 7/11, Beltrán II A and Beltrán IIB–, oil amphorae from the Guadalquivir valley –Dr. 20– and other imported ones –Dr. 2/4 and Dr. 14–). The parallels found, specially in northern Italy (area of Venice and the Po plain) and in the Rhone river let us relate this structure to a draining platform. Its location by the river side, the name of the site (“Los Cargaderos” = dockers) and the vicinity of some early roman villae show that we are in front of a small roman wharf in the Bay of Cádiz. Some observations concerning the reusing of amphorae for architectural purposes and the use of wood in the hispanorroman harbour installations are also discussed

Vertebrae reveal industrial-era increases in Atlantic bluefin tuna catch-at-size and juvenile growth

Climate change and size-selective overexploitation can alter fish size and growth, yet our understanding of how and to what extent is limited due to a lack of long-term biological data from wild populations. This precludes our ability to effectively forecast population dynamics and support sustainable fisheries management. Using modern, archived, and archaeological vertebrae dimensions and growth rings of one of the most intensely exploited populations, the eastern Atlantic and Mediterranean bluefin tuna (Thunnus thynnus, BFT), we estimated catch-at-size and early-life growth patterns from the 3 (rd) century bce to the 21 (st) century ce to understand responses to changes in its environment. We provide novel evidence that BFT juvenile growth increased between the 16 (th)-18 (th), 20 (th), and 21 (st) centuries, and is correlated with a warming climate and likely a decrease in stock biomass. We found it equally plausible that fisheries-induced evolution has acted to increase juvenile BFT growth, driving earlier maturation as a result of size-selective exploitation. Coincidently, we found limited evidence to suggest a long history of large ( >200 cm FL) BFT capture. Instead, we found that the catch-at-size of archaeological BFT was relatively small in comparison with more intensive, 20 (th) and 21 (st) century tuna trap fisheries which operated further from shore. This complex issue would benefit from studies using fine-scale biochronological analyses of otoliths and adaptation genomics, throughout the last century especially, to determine evolutionary responses to exploitation, and further disentangle the influence of temperature and biomass on fish growth

A catalogue of Spanish archaeomagnetic data

International audienceA total of 58 new archaeomagnetic directions has been determined from archaeological structures in Spain. Together with five previous results they allow the compilation of the first archaeomagnetic catalogue for Spain, which includes 63 directions with ages ranging between the 2nd century BC and the 20th century AD. Characteristic remanence directions have been obtained from stepwise thermal and alternating field demagnetization. The hierarchical structure has been respected in the calculation of the mean site directions. Rock magnetic experiments reveal that the main magnetic carrier is magnetite or titanomagnetite with different titanium contents. The age estimate of the studied structures is generally well justified by archaeological constraints. For six structures the proposed date is also supported by physical methods. The data are in close agreement with the French secular variation (SV) curve. This catalogue represents the first step in the construction of a SV curve for the Iberian Peninsula, which will be of much use in archaeomagnetic dating and in modelling of the Earth's magnetic field in Western Europe

Ancient DNA SNP-panel data suggests stability in bluefin tuna genetic diversity despite centuries of fluctuating catches in the eastern Atlantic and Mediterranean

Atlantic bluefin tuna (Thunnus thynnus; BFT) abundance was depleted in the late 20th and early 21st century due to overfishing. Historical catch records further indicate that the abundance of BFT in the Mediterranean has been fluctuating since at least the 16th century. Here we build upon previous work on ancient DNA of BFT in the Mediterranean by comparing contemporary (2009–2012) specimens with archival (1911–1926) and archaeological (2nd century BCE–15th century CE) specimens that represent population states prior to these two major periods of exploitation, respectively. We successfully genotyped and analysed 259 contemporary and 123 historical (91 archival and 32 archaeological) specimens at 92 SNP loci that were selected for their ability to differentiate contemporary populations or their association with core biological functions. We found no evidence of genetic bottlenecks, inbreeding or population restructuring between temporal sample groups that might explain what has driven catch fluctuations since the 16th century. We also detected a putative adaptive response, involving the cytoskeletal protein synemin which may be related to muscle stress. However, these results require further investigation with more extensive genome-wide data to rule out demographic changes due to overfishing, and other natural and anthropogenic factors, in addition to elucidating the adaptive drivers related to these

Fish and fishing in the Roman world

This article focuses on two aspects related to fish and fishing. It first discusses the social context for the consumption of preserved and fresh fish, showing that generally consumption of certain types of fresh fish conferred status, whereas consumption of preserved fish, being more affordable, was attested across social strata. The paper then moves on to examine the organization of the ‘fishing industry’, specifically the relationship between fish-salting establishments and the fishermen who provided the fish. Although we have many literary, documentary, and archaeological sources for fish preservation and fishing techniques in classical antiquity, the fishermen engaged in large-scale fishing remain rather elusive

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

From sea monsters to charismatic megafauna: changes in perception and use of large marine animals

Marine megafauna has always elicited contrasting feelings. In the past, large marine animals were often depicted as fantastic mythological creatures and dangerous monsters, while also arousing human curiosity. Marine megafauna has been a valuable resource to exploit, leading to the collapse of populations and local extinctions. In addition, some species have been perceived as competitors of fishers for marine resources and were often actively culled. Since the 1970s, there has been a change in the perception and use of megafauna. The growth of marine tourism, increasingly oriented towards the observation of wildlife, has driven a shift from extractive to non-extractive use, supporting the conservation of at least some species of marine megafauna. In this paper, we review and compare the changes in the perception and use of three megafaunal groups, cetaceans, elasmobranchs and groupers, with a special focus on European cultures. We highlight the main drivers and the timing of these changes, compare different taxonomic groups and species, and highlight the implications for management and conservation. One of the main drivers of the shift in perception, shared by all the three groups of megafauna, has been a general increase in curiosity towards wildlife, stimulated inter alia by documentaries (from the early 1970s onwards), and also promoted by easy access to scuba diving. At the same time, environmental campaigns have been developed to raise public awareness regarding marine wildlife, especially cetaceans, a process greatly facilitated by the rise of Internet and the World Wide Web. Currently, all the three groups (cetaceans, elasmobranchs and groupers) may represent valuable resources for ecotourism. Strikingly, the economic value of live specimens may exceed their value for human consumption. A further change in perception involving all the three groups is related to a growing understanding and appreciation of their key ecological role. The shift from extractive to non-extractive use has the potential for promoting species conservation and local economic growth. However, the change in use may not benefit the original stakeholders (e.g. fishers or whalers) and there may therefore be a case for providing compensation for disadvantaged stakeholders. Moreover, it is increasingly clear that even non-extractive use may have a negative impact on marine megafauna, therefore regulations are needed.SFRH/BPD/102494/2014, UID/MAR/04292/2019, IS1403info:eu-repo/semantics/publishedVersio