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While the four species of horseshoe crabs share many common reproductive traits with respect to their reproductive systems, they do differ with respect to their mating behavior (monogamy vs. polygynandry). Past research has attributed these differences to a number of factors including: spawning densities, operational sex ratios (OSR's), male condition (or age), environmental and/or genetic factors, or a combination thereof. Mating behaviors in the three Asian horseshoe crab species (Tachypleus gigas, T. tridentatus, and Carcinoscorpius rotundicauda) with low spawning densities and 1:1 operational sex ratios are typically monogamous. In Limulus polyphemus, mating behavior is more variable ranging from monogamy to polygynandry. Here we provide evidence, through a long term behavioral study, that variation in mating behavior is influenced by population density in L. polyphemus. Our study population on two beaches in Connecticut (Long Island Sound) have a spawning density 400 times less than that found in Delaware Bay (0.002 females/m2 vs. 0.8 females/m2) but similar operational sex ratios. Between 90%-95% of all spawning females in CT were paired with only one male, thus exhibiting monogamous behavior. In contrast, between 30 and 60% of spawning females in Delaware Bay have more than one mate and produce clutches of eggs with multiple paternities. Male condition played no role in mating behavior in CT populations. We also observed that on average 18% of the females on the spawning beaches are single. These results suggest that population density is an important condition that determines mating behavior. Also, low population density may lead to decreased mate finding ability and lost opportunities for spawning [Current Zoology 56 (5): 634-642, 2010]. © 2010 Current Zoology.

The rhizosphere in terrestrial systems is the region of soil surrounding plant roots where there is increased microbial activity; in aquatic plants, this definition may be less clear because of diffusion of nutrients in water, but there is still a zone of influence by plant roots in this environment [1]. Within that zone chemical conditions differ from those of the surrounding environment as a consequence of a range of processes that were induced either directly by the activity of plant roots or by the activity of rhizosphere microflora. Recently, there are a number of new studies related to rhizospheres of aquatic plants and specifically their increased potential for remediation of contaminants, especially remediation of metals through aquatic plant-microbial interaction. Copyright 2010 Elsevier Ltd. All rights reserved.

The adaptation of traditional, face-to-face courses to the online format presents both challenges and opportunities. Many pedagogical practices need to be rethought when designing online courses. A successful online course needs to be intellectually stimulating and engaging. The chapter demonstrates how to create an engaging learning environment without any additional budget. The author describes approaches that she has developed, experimented with, and found to be effective in asynchronous online art history courses, as well as learner engagement strategies she has implemented in the eLearning environment. Advantages of scenario-based discussions board assignments and the effects of role playing in discussion forums are discussed. The author shares examples of personalized discussion board assignments aimed to motivate online learners, create a collaborative learning environment, improve peer-to-peer interaction, and prevent plagiarism.

"Frans Hals and the Vernacular" published on 01 Jan 2012 by Brill.

"Medieval renaissance Baroque" celebrates Marilyn Aronberg Lavin's breakthrough achievements in both the print and digital realms of art and cultural history. Fifteen friends and colleagues present tributes and essays that reflect every facet of this renowned scholar's brilliant career. Tribute presenters include Ellen Burstyn, Langdon Hammer, Phyllis Lambert, and James Marrow. Contributors include Kirk Alexander, Horst Bredekamp, Nicola Courtright, David Freedberg, Jack Freiberg, Marc Fumaroli, David A. Levine, Daniel T. Michaels, Elizabeth Pilliod, Debra Pincus, and Gary Schwartz. 79 illustrations, bibliography of Marilyn Lavin's works, index.

"Reflects Marilyn Aronberg Lavin's innovative work in art and cultural history in both the print and digital realms. Contributors: Kirk Alexander, Horst Bredekamp, Nicola Courtright, David Freedberg, Jack Freiberg, Marc Fumaroli, David A. Levine, Daniel T. Michaels, Elizabeth Pilliod, Debra Pincus, Gary Schwartz. Seventy-seven illustrations, bibliography of Lavin's works, index"--Provided by publisher.

Since 2000, significant collections of Latest Miocene hominin fossils have been recovered from Chad, Kenya, and Ethiopia. These fossils have provided a better understanding of earliest hominin biology and context. Here, we describe five hominin teeth from two periods (ca. 5.4 Million-years-ago and ca. 6.3 Ma) that were recovered from the Adu-Asa Formation in the Gona Paleoanthropological Research Project area in the Afar, Ethiopia that we assign to either Hominina, gen. et sp. indet. or Ardipithecus kadabba. These specimens are compared with extant African ape and other Latest Miocene and Early Pliocene hominin teeth. The derived morphology of the large, non-sectorial maxillary canine and mandibular third premolar links them with later hominins and they are phenetically distinguishable and thus phyletically distinct from extant apes. Copyright © 2014 Elsevier Ltd. All rights reserved.

This article argues that the Acheulean is perhaps the longest lasting cultural–technological tradition in human history, dating from around 1.7 to 0.3 Mya and roughly corresponding to the time during which H. Erectus and H. Heidelbergensis lived in Africa. Unlike earlier Oldowan technology, Acheulean cores — handaxes, cleavers, and picks — were standardised, of predetermined shape and made on large cobbles and flakes. The extensive Acheulean archaeological record throughout Africa over 1.4 million years described is testimony to the success of this technology’s makers in different habitats, altitudes, and settings, but also to its apparent conservative cultural nature: a learned tradition passed on through thousands of generations of highly mobile hominin groups with small population sizes. Although there are differences between Early and Late Acheulean technology, the makers of these tools may have undergone more significant changes with respect to the use of other technologies, strategic land use, and social life.

In this article, I examine the statements and actions of two key informants, both of whom direct welfare programs in a district of the former East Berlin. I argue that this evidence points to a particular modality of political rationalization, which I dub organizational discourse. The entanglement of organizational discourse and governmentality are explored, as is the place of organizational discourse within both the liberal welfare state and the bygone state socialist regime.

Use-value and exchange-value are pragmatic features of commodity exchange which are apparent from the careful study of specific interactions, as well as from the viewpoint of economic processes at large. While Marx's well-known attempt to describe this pair of concepts in Capital (2001) takes the latter tack, I attempt here to take the formeri.e., to approach the composition of the commodity from the point of view of the pragmatics of interaction. In doing so, I offer a semiotic model of the valuation of commodities which differs from accounts given by Kockelman (2006) and Agha (2011). The ethnographic object at stake in this essay is StreetWise, a Chicago street newspaper said to have empowering effects on its vendors.

Human sacrifice in the Inca Empire at times took the form of the capacocha, a sacrificial rite involving the most beautiful children in the empire. In this study, we investigate a possible capacocha at the pre-Columbian site of Choquepukio in the Cuzco Valley of Peru. During excavations at Choquepukio in 2004, seven children (aged 3-12 years) were discovered buried together; accompanying them was an elaborate assemblage of high status artifacts similar to those from other recent archaeological finds that are believed to be capacocha sacrifices. Since colonial documents indicate that capacocha children were selected from diverse regions of the empire, we initiated a radiogenic strontium isotope analysis to determine the origins of the children found at Choquepukio. Our analysis showed that, indeed, two children in the assemblage had non-local origins. When considered together, the osteological, archaeological, and isotopic evidence suggest that a capacocha event occurred at Choquepukio, representing the only lower-elevation capacocha to have been found in the Cuzco region. (C) 2010 Elsevier Ltd. All rights reserved.