A recent development in biology has been the growing acceptance that holobionts, entities comprised of symbiotic microbes and their host organisms, are widespread in nature. There is agreement that holobionts are evolved outcomes, but disagreement on how to characterize the operation of natural selection on them. The aim of this paper is to articulate the contours of the disagreement. I explain how two distinct foundational accounts of the process of natural selection give rise to competing views about evolutionary individuality.

Among mycologists, questions persist about what entities should be treated as the fundamental units of fungal populations. This article articulates a coherent view about populations of heterokaryotic fungi and the individuals that comprise them. Using Godfrey-Smith’s minimal concept of a Darwinian population, I argue that entities at two levels of the biological hierarchy satisfy the minimal concept in heterokaryotic fungi: mycelia and nuclei. I provide a preliminary answer to the question of how to understand the relation between these two populations. (...) This article contributes to discussions about the nature of biological individuality, organismality, and evolutionary transitions. (shrink)

Eukaryogenesis is widely viewed as an improbable evolutionary transition uniquely affecting the evolution of life on this planet. However, scientific and popular rhetoric extolling this event as a singularity lacks rigorous evidential and statistical support. Here, we question several of the usual claims about the specialness of eukaryogenesis, focusing on both eukaryogenesis as a process and its outcome, the eukaryotic cell. We argue in favor of four ideas. First, the criteria by which we judge eukaryogenesis to have required a genuinely (...) unlikely series of events 2 billion years in the making are being eroded by discoveries that fill in the gaps of the prokaryote:eukaryote “discontinuity.” Second, eukaryogenesis confronts evolutionary theory in ways not different from other evolutionary transitions in individuality; parallel systems can be found at several hierarchical levels. Third, identifying which of several complex cellular features confer on eukaryotes a putative richer evolutionary potential remains an area of speculation: various keys to success have been proposed and rejected over the five-decade history of research in this area. Fourth, and perhaps most importantly, it is difficult and may be impossible to eliminate eukaryocentric bias from the measures by which eukaryotes as a whole are judged to have achieved greater success than prokaryotes as a whole. Overall, we question whether premises of existing theories about the uniqueness of eukaryogenesis and the greater evolutionary potential of eukaryotes have been objectively formulated and whether, despite widespread acceptance that eukaryogenesis was “special,” any such notion has more than rhetorical value. (shrink)

That holobionts are units of selection squares poorly with the observation that microbes are often recruited from the environment, not passed down vertically from parent to offspring, as required for collective reproduction. The taxonomic makeup of a holobiont’s microbial community may vary over its lifetime and differ from that of conspecifics. In contrast, biochemical functions of the microbiota and contributions to host biology are more conserved, with taxonomically variable but functionally similar microbes recurring across generations and hosts. To save what (...) is of interest in holobiont thinking, we propose casting metabolic and developmental interaction patterns, rather than the taxa responsible for them, as units of selection. Such units need not directly reproduce or form parent-offspring lineages: their prior existence has created the conditions under which taxa with the genes necessary to carry out their steps have evolved in large numbers. These taxa or genes will reconstruct the original interaction patterns when favorable conditions occur. Interaction patterns will vary in ways that affect the likelihood of and circumstances under which such reconstruction occurs. Thus, they vary in fitness, and evolution by natural selection will occur at this level. It is on the persistence, reconstruction, and spread of such interaction patterns that students of holobiosis should concentrate, we suggest. This model also addresses other multi-species collectively beneficial interactions, such as biofilms or biogeochemical cycles maintaining all life. (shrink)

In recent years there has been a major revival of interest in the political philosophy of Immanuel Kant. Thinkers have looked to Kant's theories about knowledge, history, the moral self and autonomy, and nature and aesthetics to seek the foundations of their own political philosophy. This volume, written by established authorities on Kant as well as by new scholars in the field, illuminates the ways in which contemporary thinkers differ regarding Kantian philosophy and Kant's legacy to political and ethical theory. (...) The book contains essays by Patrick Riley, Lewis White Beck, Mary Gregor, and Richard L. Velkley that place Kant in the tradition of political philosophy; chapters by Dieter Henrich, Susan Shell, Michael W. Doyle, and Joseph M. Knippenberg that examine Kantian perspectives on history and politics; contributions by William A. Galston, Bernard Yack, William James Booth, and Ronald Beiner that judge the Kantian legacy; and classic discussions by John Rawls, Jürgen Habermas, Charles Taylor, and Hans-Georg Gadamer that present different perspectives on contemporary debates about Kant. (shrink)

Improvement in performance after the end of the training session, termed “Offline improvement,” has been shown in procedural learning tasks. We examined whether Offline improvement in learning a novel orthography depends on the type of reading instruction. Forty-eight adults received multisession training in reading nonsense words, written in an artificial script. Participants were trained in one of three conditions: alphabetical words preceded by direct letter instruction (Letter-Alph); alphabetical words with whole-word instruction (Word-Alph); and nonalphabetical (arbitrary) words with whole-word instruction (Word-Arb). (...) Offline improvement was found only for the Letter-Alph group. Moreover, correlation with a standardized measure of word reading ability showed that good readers trained in the Letter-Alph group exhibit greater Offline improvement, whereas good readers trained in the Word-Arb group showed greater Within-session improvement during training. These results suggest that different consolidation processes and learning mechanisms were involved in each group. We argue that providing a short block of direct letter instruction prior to training resulted in increased involvement of procedural learning mechanisms during training. (shrink)

Efforts to address algorithmic harms have gathered particular steam over the last few years. One area of proposed opportunity is the notion of an “algorithmic audit,” specifically an “internal audit,” a process in which a system’s developers evaluate its construction and likely consequences. These processes are broadly endorsed in theory—but how do they work in practice? In this paper, we conduct not only an audit but an autoethnography of our experiences doing so. Exploring the history and legacy of a facial (...) recognition dataset, we find paradigmatic examples of algorithmic injustices. But we also find that the process of discovery is interwoven with questions of affect and infrastructural brittleness that internal audit processes fail to articulate. For auditing to not only address existing harms but avoid producing new ones in turn, we argue that these processes must attend to the “mess” of engaging with algorithmic systems in practice. Doing so not only reduces the risks of audit processes but—through a more nuanced consideration of the emotive parts of that mess—may enhance the benefits of a form of governance premised entirely on altering future practices. (shrink)

Type II DNA topoisomerase activity is required to change DNA topology. It is important in the relaxation of DNA supercoils generated by cellular processes, such as transcription and replication, and it is essential for the condensation of chromosomes and their segregation during mitosis. In mammals this activity is derived from at least two isoforms, termed DNA topoisomerase IIα and β. The α isoform is involved in chromosome condensation and segregation, whereas the role of the β isoform is not yet clear. (...) DNA topoisomerase IIβ was first reported in 1987. Here we review the research on DNA topoisomerase IIβ over the last 10 years. BioEssays 20:215–226, 1998.© 1998 John Wiley & Sons, Inc. (shrink)

Each year in the UK there are approximately 250,000 miscarriages, 3,000 stillbirths and 3,000 terminations following a diagnosis of fetal-abnormality. This paper draws from original empirical research into the experience of pregnancy loss and the accompanying decisionmaking processes. A key finding is that there is considerable variation across England in the range of options that are offered for disposal of pregnancy remains and the ways in which information around disposal are communicated. This analysis seeks to outline the key features of (...) what constitutes effective communication in this context, where effective communication is taken to mean that patients are provided with the key information necessary, in an appropriate manner, so that they are fully able to make a decision. A primary source of evidence includes interviews with the bereaved and pregnancy-loss support workers, in order to understand how the options available, and associated necessary procedures, are communicated. In addition, patient information leaflets are also analyzed as they offer an important tool for information delivery at a difficult and emotionally charged time. Following this, an overview is provided of the information that these leaflets should contain, along with guidance on effective presentation of this information. (shrink)

This chapter contains sections titled: A Runner is Born A Runner's Conversion to Cycling A Few Lessons from a Relatively New Convert The End of the Tour Notes.

The word ‘tyrant’ was not originally Greek, but borrowed from some eastern language, perhaps in western Asia Minor. On the other hand, tyranny as it developed in the Greek cities in the archaic age would seem to have been initially an indigenous growth, independent of any intervention by foreign powers. It then became a constantly recurring phenomenon of Greek political and social life, so long as the Greeks enjoyed an independent history.

On Aen. 2. 277 DServius notes ‘non sine ratione etiam hoc de crinibus dolet Aeneas, quia illis maxime Hector commendabatur, adeo ut etiam tonsura ab eo nomen acceperit, sicut Graeci poetae docent.’ Fraenkel showed that the reference in Graeci poetae is to Lycophron , the source of the comment being provided by Eustathius 1276. 29, a scholion on Il. 22. 401 f. He adds a caution against supposing that Servius’ source referred not only to Lycophron but also to other Greek (...) poets, ‘e.g. some Attic comedians’. That such allusions were in fact made in Comedy is proved by Pollux. (shrink)

From his own experience the author has found that searching and finding out that God has created a perfect world/universe relieves him of the stress and pressure of being in a world/universe of total confusion and turmoil while trying to make sense out of his daily struggles of living.

Understanding how best to educate for sustainability must be a priority in this time of environmental uncertainty. This commentary examines the role of inquiry-based learning in education for ….