Paratuberculosis y amiloidosis en gacelas

Trabajo presentado a la: XXXIII Reunión de la Sociedad Española de Anatomía Patológica Veterinaria (SEAPV). Lugo. P12. 15-17 junio

Beaching of the tunicate Salpa thompsoni at high levels of suspended particulate matter in the Southern Ocean

A mass death event of the pelagic tunicate Salpa thompsoni, which occurred in April 2002 in the Potter Cove, near the Argentinean/German Antarctic station Jubany (62°14S 58°40W), King George Island, South Shetland Islands, is described. Salps appeared on the beach two days after very strong (> 80 km.h-1) winds were registered, which accumulated particulate material in the inner part of the cove and probably also re-suspended bottom sediments. The sharp increase in particulate matter concentrations in Potter Cove caused clogging (sensu Harbison et al. 1986) of salp mucous filtering nets and likely a combination of clogging, winds and tides caused dying salps to be washed out on the beach. Until further research, it may be postulated that particle concentrations exceeding 20 mgDW.l-1 could be considered as natural threshold concentrations for S. thompsoni in the high Antarctic coastal regions

Expanding the scope of Actualistic Taphonomy in Archaeological Research

This chapter presents the application of actualistic taphonomy to the study of one of the inorganic remains produced by hominins since 3 million year BP up to historical times: lithic artifacts. As rocks are among the most durable raw materials employed by modern humans and their ancestors, differential preservation has conferred a leading role in archaeological research upon lithic artifacts. Indeed, lithics -flaked artifacts in particular- are the proxy for culture or anthropic presence most commonly used by scholars all over the world. This artifact-human relationship promoted actualistic research on flintknapping in archaeology but no similar effort was devoted to assessing alternative non-cultural (i.e. taphonomic) sources for flaked stone objects. Even though actualistic studies have already shown that taphonomic processes may produce lithic pseudomorphs, this fact is only rarely considered in archaeological practice and research design. Furthermore, it is commonly assumed that human products are different enough from any natural specimen to be detected by lithic analysts. However, the current lack of knowledge on non-cultural flaking processes and their byproducts prevents their identification in the archaeological record, thus undermining the accuracy and reliability of archaeological interpretations. This paper illustrates the contribution of actualistic taphonomy to study the inorganic remains of the archaeological record and its critical role in assessing the cultural vs natural origin of lithic specimens in Fuego-Patagonia (South America). Naturalistic and experimental research on rockfall and trampling presented here suggests that the effects of these taphonomic processes result in pseudoartifacts that progressively incorporate to the regional archaeological record.Fil: Borrazzo, Karen Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Multidisciplinario de Historia y Ciencias Humanas; Argentin