Medieval Whalers in the Netherlands and Flanders: Zooarchaeological Analysis of Medieval Cetacean Remains
ENVIRONMENTAL ARCHAEOLOGY
Authors: van den Hurk, Youri; Spindler, Luke; McGrath, Krista; Speller, Camilla
Abstract
Medieval historical sources suggest that cetacean exploitation was, for large parts of Europe, restricted to the social elite. This appears to have also been the case for the Netherlands and Flanders. It remains unclear, however, how frequently active hunting was undertaken, and which species were targeted. Zooarchaeological cetacean remains are often recovered from Medieval (AD 400-1600) sites in the Netherlands and Flanders, however the majority of these specimens have not been identified to the species level, leaving a substantial gap in our knowledge of past cetacean exploitation. By applying ZooMS, as well as morphological and osteometric analyses, these zooarchaeological specimens were identified to the species level. This analysis revealed that the North Atlantic right whale (Eubalaena glacialis), sperm whale (Physeter macrocephalus), and grey whale (Eschrichtius robustus) were frequently exploited. Active whaling appears to have been undertaken as well, especially in Flanders and in Frisia (the northern part of the Netherlands). Zooarchaeological cetacean remains appear to be present with relative frequency at high-status sites such as castles, as well as ecclesiastical sites, confirming the historical evidence that the social elite indeed did have a taste for cetacean meat. However, cetacean products were also available outside of elite and ecclesiastical contexts.
Seeing is believing: Current methods to observe sperm acrosomal exocytosis in real time
MOLECULAR REPRODUCTION AND DEVELOPMENT
Authors: Balestrini, Paula A.; Jablonski, Martina; Schiavi-Ehrenhaus, Liza J.; Marin-Briggiler, Clara, I; Sanchez-Cardenas, Claudia; Darszon, Alberto; Krapf, Dario; Buffone, Mariano G.
Abstract
Acrosomal exocytosis (AR) is a critical process that sperm need to undergo to fertilize an egg. The evaluation of the presence or absence of the acrosome is usually performed by using lectins or dyes in fixed cells. With this approach, it is neither possible to monitor the dynamic process of exocytosis and related molecular events while discriminating between live and dead cells, nor to evaluate the acrosomal status while sperm reside in the female reproductive tract. However, over the last two decades, several new methodologies have been used to assess the occurrence of AR in living cells allowing different groups to obtain information that was not possible in the past. These techniques have revolutionized the whole study of this process. This review summarizes current methods available to analyze AR in living cells as well as the important information that emerged from studies using these approaches.