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Organizational adaptation is a ubiquitous concept in management and organization research. Discussed in many theories, sometimes under different labels, the notion of adaptation is related to organizations being congruent to the environments within which they operate. Research traditions including behavioral theory (see A Behavioral Theory of the Firm), contingency theory as explained in Differentiation and Integration in Complex Organizations, population ecology (see The Population Ecology of Organizations), institutional theory elaborated upon in both Institutionalized Organizations: Formal Structure as Myth and Ceremony and The Iron Cage Revisited: Institutional Isomorphism and Collective Rationality in Organizational Fields, resource dependence (see The External Control of Organizations: A Resource Dependence Perspective), and evolutionary economics (see An Evolutionary Theory of Economic Change) all address organizational adaptation—though they emphasize different mechanisms. Adaptation, regarded as the strategic choice that organizations make, is often contrasted with the notion of selection driven by the determinism imposed by environments (see Organizational Adaptation: Strategic Choice and Environmental Determinism). Adaptive organizations are those able to obtain congruence both within organizations, reflected as congruence in internal functions and strategies, and across organizations, reflected as congruence with the needs of the external environment. The form of adaptation is also particularly relevant. Organizational theory has viewed adaptation as a state, an ability, and as a process. States of adaptation discuss stability and adaptation at points in time. From states of adaptation, adaptive abilities determine the impetus of adaptation and the locus of adaptation within organizations. Finally, the adaptation processes describe the means by which organizations adapt the challenges they face in negotiating new positions within environments. Research has covered each of these areas and this bibliography is organized primarily around forms of adaptation to elaborate on the ways in which it has been viewed by organizational theory and strategy scholars. The variety of research traditions examining organizational adaptation have not always aligned, however. Each research tradition seeks to explain different outcomes, from survival to performance to change. Thus, across theoretical traditions, the adaptation construct has been measured in many different ways—and often not as congruence with the external environment. In fact, this represents one of the challenges that recent research has identified as holding back progression of the adaptation research agenda. As such, this bibliography concludes with a section on issues in adaptation research in order to assist researchers in pursuing research in this area.

International audience; Many software systems today provide support for adaptation and reconfiguration at runtime, in response to changes in their environment. Such adaptive systems are designed to run continuously and may not be shut down for reconfiguration or maintenance tasks. The variability of such systems has to be explicitly managed, together with mechanisms that control their runtime adaptation and reconfiguration. Dynamic software product lines (DSPLs) can help to achieve this. However, dealing with evolution is particularly challenging in a DSPL, as changes made at run-time can easily lead to inconsistencies. This paper describes the challenges of evolving DSPLs using an example cyber-physical system for home automation. We discuss the shortcomings of existing work and present a reference architecture to support DSPL evolution. To demonstrate its feasibility and flexibility, we implemented the proposed reference architecture for two different DSPLs: the aforementioned cyber-physical system, which uses feature models to describe its variability, and a runtime monitoring infrastructure, which is based on decision models. To assess the industrial applicability of our approach, we also implemented the reference architecture for a real-world DSPL, an automation software system for injection molding machines. Our results provide evidence on the flexibility, performance and industrial applicability of our approach.

Erratum in : Correction for Adam et al., Evolutionary history of carbon monoxide dehydrogenase/acetyl-CoA synthase, one of the oldest enzymatic complexes. [Proc Natl Acad Sci U S A. 2018]; International audience; Carbon monoxide dehydrogenase/acetyl-CoA synthase (CODH/ ACS) is a five-subunit enzyme complex responsible for the carbonyl branch of the Wood-Ljungdahl (WL) pathway, considered one of the most ancient metabolisms for anaerobic carbon fixation, but its origin and evolutionary history have been unclear. While traditionally associated with methanogens and acetogens, the presence of CODH/ACS homologs has been reported in a large number of un-cultured anaerobic lineages. Here, we have carried out an exhaustive phylogenomic study of CODH/ACS in over 6,400 archaeal and bacterial genomes. The identification of complete and likely functional CODH/ACS complexes in these genomes significantly expands its distribution in microbial lineages. The CODH/ACS complex displays astounding conservation and vertical inheritance over geological times. Rare intradomain and interdomain transfer events might tie into important functional transitions, including the acquisition of CODH/ACS in some archaeal methanogens not known to fix carbon, the tinkering of the complex in a clade of model bacterial acetogens, or emergence of archaeal-bacterial hybrid complexes. Once these transfers were clearly identified, our results allowed us to infer the presence of a CODH/ACS complex with at least four subunits in the last universal common ancestor (LUCA). Different scenarios on the possible role of ancestral CODH/ACS are discussed. Despite common assumptions, all are equally compatible with an autotrophic, mixotrophic, or heterotrophic LUCA. Functional characterization of CODH/ACS from a larger spectrum of bacterial and archaeal lineages and detailed evolutionary analysis of the WL methyl branch will help resolve this issue.

Estimating the rates at which bacterial genomes evolve is critical to understanding major evolutionary and ecological processes such as disease emergence, long-term host-pathogen associations, and short-term transmission patterns. The surge in bacterial genomic data sets provides a new opportunity to estimate these rates and reveal the factors that shape bacterial evolutionary dynamics. For many organisms estimates of evolutionary rate display an inverse association with the time-scale over which the data are sampled. However, this relationship remains unexplored in bacteria due to the difficulty in estimating genome-wide evolutionary rates, which are impacted by the extent of temporal structure in the data and the prevalence of recombination. We collected 36 whole genome sequence data sets from 16 species of bacterial pathogens to systematically estimate and compare their evolutionary rates and assess the extent of temporal structure in the absence of recombination. The majority (28/36) of data sets possessed sufficient clock-like structure to robustly estimate evolutionary rates. However, in some species reliable estimates were not possible even with “ancient DNA” data sampled over many centuries, suggesting that they evolve very slowly or that they display extensive rate variation among lineages. The robustly estimated evolutionary rates spanned several orders of magnitude, from 10−6 to 10−8 nucleotide substitutions site-1 year-1. This variation was largely attributable to sampling time, which was strongly negatively associated with estimated evolutionary rates, with this relationship best described by an exponential decay curve. To avoid potential estimation biases such time-dependency should be considered when inferring evolutionary time-scales in bacteria.

In invasion ecology, reliable measures of female fecundity are necessary to infer population growth rate and develop control programs to determine the proportion of animals that should be culled to reduce population size. Here, we present a reliable staining technique of uterine scars to determine individual fecundity in terms of both seasonal and total (annual) number of young born per female. We applied this method to two alien squirrels species (grey squirrel, Sciurus carolinensis and Pallas’s squirrel, Callosciurus erythraeus) introduced in Northern Italy, obtaining carcasses from control campaigns from 2011 to 2013. We also investigated environmental and phenotypic variables that might affect individual variation in fecundity and compared annual reproductive output between the two species. For grey squirrels (n=44), 25% of examined females produced a single litter and 61% two litters. Females which reproduced in both seasons tended to have larger summer than spring litters (on average 2.61 and 1.94 offspring, respectively) and mean annual fecundity was 3.4 scars/female ranging from 1 to 8 births. There was no effect of year, eye lens weight, body size or body mass on total fecundity. For Pallas’s squirrel (n=31), 58% of females had a spring litter, some of these also produced a summer litter (35%) and a few even a third litter in autumn (10%). Heavier and older females (higher eye lens weight) had more uterine scars than younger animals with lower body mass. Finally, fecundity of the two IAS in Italy was similar or even higher than in the native range and/or in other countries of introduction, suggesting they are well adapted to their new environment and potentially have a high capacity to spread and recover after reduction of population size. Download the complete issue.