Superorganisms of the protist kingdom : a new level of biological organization

The concept of superorganism has a mixed reputation in biology-for some it is a convenient way of discussing supra-organismal levels of organization, and for others, little more than a poetic metaphor. Here, I show that a considerable step forward in the understanding of superorganisms results from a thorough review of the supra-organismal levels of organization now known to exist among the “unicellular” protists. Limiting the discussion to protists has enormous advantages: their bodies are very well studied and relatively simple (as compared to humans or termites, two standard examples in most discussions about superorganisms), and they exhibit an enormous diversity of anatomies and lifestyles. This allows for unprecedented resolution in describing forms of supra-organismal organization. Here, four criteria are used to differentiate loose, incidental associations of hosts with their microbiota from “actual” superorganisms: (1) obligatory character, (2) specific spatial localization of microbiota, (3) presence of attachment structures and (4) signs of co-evolution in phylogenetic analyses. Three groups-that have never before been described in the philosophical literature-merit special attention: Symbiontida (also called Postgaardea), Oxymonadida and Parabasalia. Specifically, it is argued that in certain cases-for Bihospites bacati and Calkinsia aureus (symbiontids), Streblomastix strix (an oxymonad), Joenia annectens and Mixotricha paradoxa (parabasalids) and Kentrophoros (a ciliate)-it is fully appropriate to describe the whole protist-microbiota assocation as a single organism (“superorganism”) and its elements as “tissues” or, arguably, even “organs”. To account for this level of biological complexity, I propose the term “structured superorganism”

Distribution and Phylogeny of EFL and EF-1α in Euglenozoa Suggest Ancestral Co-Occurrence Followed by Differential Loss

BACKGROUND: The eukaryotic elongation factor EF-1alpha (also known as EF1A) catalyzes aminoacyl-tRNA binding by the ribosome during translation. Homologs of this essential protein occur in all domains of life, and it was previously thought to be ubiquitous in eukaryotes. Recently, however, a number of eukaryotes were found to lack EF-1alpha and instead encode a related protein called EFL (for EF-Like). EFL-encoding organisms are scattered widely across the tree of eukaryotes, and all have close relatives that encode EF-1alpha. This intriguingly complex distribution has been attributed to multiple lateral transfers because EFL's near mutual exclusivity with EF-1alpha makes an extended period of co-occurrence seem unlikely. However, differential loss may play a role in EFL evolution, and this possibility has been less widely discussed. METHODOLOGY/PRINCIPAL FINDINGS: We have undertaken an EST- and PCR-based survey to determine the distribution of these two proteins in a previously under-sampled group, the Euglenozoa. EF-1alpha was found to be widespread and monophyletic, suggesting it is ancestral in this group. EFL was found in some species belonging to each of the three euglenozoan lineages, diplonemids, kinetoplastids, and euglenids. CONCLUSIONS/SIGNIFICANCE: Interestingly, the kinetoplastid EFL sequences are specifically related despite the fact that the lineages in which they are found are not sisters to one another, suggesting that EFL and EF-1alpha co-occurred in an early ancestor of kinetoplastids. This represents the strongest phylogenetic evidence to date that differential loss has contributed to the complex distribution of EFL and EF-1alpha

Introduction: Toward an Engaged Feminist Heritage Praxis

We advocate a feminist approach to archaeological heritage work in order to transform heritage practice and the production of archaeological knowledge. We use an engaged feminist standpoint and situate intersubjectivity and intersectionality as critical components of this practice. An engaged feminist approach to heritage work allows the discipline to consider women’s, men’s, and gender non-conforming persons’ positions in the field, to reveal their contributions, to develop critical pedagogical approaches, and to rethink forms of representation. Throughout, we emphasize the intellectual labor of women of color, queer and gender non-conforming persons, and early white feminists in archaeology

Genetic tool development in marine protists: emerging model organisms for experimental cell biology

Abstract: Diverse microbial ecosystems underpin life in the sea. Among these microbes are many unicellular eukaryotes that span the diversity of the eukaryotic tree of life. However, genetic tractability has been limited to a few species, which do not represent eukaryotic diversity or environmentally relevant taxa. Here, we report on the development of genetic tools in a range of protists primarily from marine environments. We present evidence for foreign DNA delivery and expression in 13 species never before transformed and for advancement of tools for eight other species, as well as potential reasons for why transformation of yet another 17 species tested was not achieved. Our resource in genetic manipulation will provide insights into the ancestral eukaryotic lifeforms, general eukaryote cell biology, protein diversification and the evolution of cellular pathways

Several wood for several uses. Exploitation and selection at the pile-dwelling cave settlement Grotta di Pertosa

Grotte di Pertosa is a natural karst cave located on the northeastern slopes of the Alburni Mountains in Campania (Southern Italy). This cave housed a pile-dwelling settlement during the Middle and Late Bronze Age. A peculiar aspect of this archaeological site is the preservation of the protohistoric wooden structures thanks to the waters of the underground stream flowing in the cave. The most impressive evidence comprises the floors of two different pile-dwelling levels, which were first excavated in the late nineteenth century by Patroni and Carucci. These scholars published data concerning both the structures and the wooden artifacts discovered. Therefore, in this paper, a review of the inferred archaeobotanical data from their studies is provided. Fortunately, several wooden poles have been preserved in the riverbed area; they are still accessible and represent the main subject of this work. So far 86 poles, still deeply driven into the riverbed, have been identified and registered. Microscopic wood analysis has been conducted on 46 samples taken from as many poles during the 2009-2013 research campaigns; furthermore 20 wood samples of uncertain attribution, found in a rich organic material layer, have also been analyzed as well as charcoal preserved in the same archaeological stratum. A first result from this study is related to paleoenvironmental issues. The comparison between the archaeobotanical assemblages and the modern surrounding vegetation, in light of the paleoclimatic data available in the literature, allowed us to elaborate on a preliminary paleoenvironmental reconstruction and to speculate about the catchment areas of wood exploited. The archaeobotanical study provided also information about wood used for different purposes: building material, fuel and craft-activities

A RADIOCARBON CHRONOLOGY FOR "GROTTE DI PERTOSA" IN CAMPANIA, SOUTHERN ITALY

The Pertosa Caves, today also known as the Pertosa-Auletta Caves, constitute an important karst system in the Campania region (southern Italy). Crossed by the waters of a river that re-emerges on the surface, they have an overall development of about 3 km. Thanks to the width of the entrance, the excellent location along a natural communication route through the mountains and the natural availability of water directly on the site, the initial part of the cavity was frequented by humans, without interruption, from prehistoric times to the Middle Ages. During the protohistory, in particular, the moment of most marked human presence is recorded in the cave. In this phase an extensive pile dwelling system was built on the waters of the underground river. The system was probably created to make the location, subject to frequent flooding, suitable for human settlement. This structure today constitutes an archaeological unicum not only in Italy but throughout Europe. We briefly analyze its general characteristics providing the results of a radiocarbon dating campaign which allowed to assess the occupation phases of the different contexts and the life span of the wooden artifacts, which came to us in a very good state of preservation. Radiocarbon data allowed to assess the chronological range of the human frequentation of the caves and to date the exceptionally well preserved underground pile dwelling system

Violence against children:preliminary evidence from Colombia, El Salvador, Cambodia and Ecuador.

The issue of child abuse in developing countries is of utmost importance for designing policies directed to vulnerable children and aimed at combating the worst forms of child labour. Unfortunately there is limited empirical basis for formulating policies and programmes addressing violence against children in developing countries. This preliminary study uses data from El Salvador(SIMPOC 2001), Colombia (SIMPOC 2001), Cambodia (SIMPOC, 2001) and Ecuador (SIMPOC, 2001) and constitutes a starting point for a more detailed analysis of the issue of children abuse.

Life cycle assessment of an innovative cogeneration system based on the aluminum combustion with water

The continuous increase in primary energy demand and the decrease in the availability of fossil fuels were led to a condition of energy security concerns. In this context, hydrogen can be seen as a promising energy carriers. This paper investigated the environmental performance, through Life Cycle Assessment (LCA) methodology, of a combined production system of hydrogen and power based on aluminum combustion with water. This system is potentially able to produce the integrated generation of four energy sources: hydrogen, high temperature steam, heat and work at the turbine shaft. The LCA results indicated that the life-cycle phases that determine the main environmental impact are: liquid aluminum production, transports of liquid aluminum and electricity consumption. In addition, the major release of carbon dioxide emissions is due to the use of natural gas in the aluminum production phase. In order to determine the “greener” alternative and support the system design choices, according to the eco-design perspective, different system configurations were investigated. In particular, the reaction mechanism between first primary aluminum powder and water steam and then secondary aluminum at liquid state and water steam. The environmental comparison highlighted that the former layout increases by more than 78% compared to latter one