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Radiation into different environments is a common evolutionary phenomenon in plants. This process has been extensively documented in oceanic islands and to a lesser extent in continental areas. The genus Hypochaeris (Asteraceae: Cichorieae) contains 41 species in South America that have evolved during the past one million years. Dispersal of propagules to new regions followed by speciation at the diploid level into different ecological zones has resulted in radiated groups. One such group, the H. apargioides complex, consists of four closely related species, H. apargioides, H. gayana, H. spathulata, and H. thrincioides, all of which are distributed in central-south Chile and adjacent Argentina. Morphometric and molecular (AFLP) data were used to help reveal processes involved in the evolution of the complex. A total of 54 populations were sampled: 34 were analyzed morphometrically and 45 were examined for genetic variation and divergence using AFLP methodology. Morphometric analysis shows that two species, H. gayana and H. spathulata, are clearly separated phenotypically from the others, but that//, apargioides and H. thrincioides are more similar to each other. The principal environmental conditions influencing morphology and distribution of species in the H. apargioides complex appear to be salinity and elevation in H. spathulata and H. gayana, respectively, and climate in H. apargioides and H. thrincioides. The overall pattern in the evolution of the complex is one of subtle morphological divergence in response to environmental selection, perhaps reflecting initial stages of adaptive radiation. The low level of molecular divergence among species also suggests rapid speciation. [ABSTRACT FROM AUTHOR]

Cannabaceae includes ten genera that are widely distributed in tropical to temperate regions of the world. Because of limited taxon and character sampling in previous studies, intergeneric phylogenetic relationships within this family have been poorly resolved. We conducted a molecular phylogenetic study based on four plastid loci (atpB-rbcL, rbcL, rpsl6, trnL-trnF) from 36 ingroup taxa, representing all ten recognized Cannabaceae genera, and six related taxa as outgroups. The molecular results strongly supported this expanded family to be a monophyletic group. All genera were monophyletic except for Trema, which was paraphyletic with respect to Parasponia. The Aphananthe clade was sister to all other Cannabaceae, and the other genera formed a strongly supported clade further resolved into a Lozanella clade, a Gironniera clade, and a trichotomy formed by the remaining genera. Morphological ancestral state reconstructions indicated the complex evolution pattern of most analyzed morphological characters, and it is difficult to identify morphological synapomorphies for most clades within Cannabaceae. [ABSTRACT FROM AUTHOR]

Abstract: Aptamers are promising gene components that can be used for the construction of synthetic gene circuits. In this study, we isolated an RNA aptamer that specifically inhibits transcription of T7 RNA polymerase (RNAP). The 38-nucleotide aptamer, which was a shortened variant of an initial SELEX isolate, showed moderate inhibitory activity. By stepwise doped-SELEX, we isolated evolved variants with strong inhibitory activity. A 29-nucleotide variant of a doped-SELEX isolate showed 50% inhibitory concentration at 11 nM under typical in vitro transcription conditions. Pull-down experiments revealed that the aptamer inhibited the association of T7 RNAP with T7 promoter DNA. [Copyright &y& Elsevier]

Molecular phylogenetic analysis of the mitochondrial small subunit and nuclear large subunit ribosomal DNA re- vealed that the lichen genus Graphis sensu Staiger represents two separate lineages. Graphis s.str. comprises the species of the G. scripta and G. subserpentina groups (`Eugraphis'), as well as the G. striatula group sensu Lucking. For the segregate genus, the name ,4llographa Chevall. is available, and this genus includes the G. acharii, G. dussii, G. marginata, G. nuda, and G. symplecta groups. The separation of both lineages is supported by principal component analysis species ordination based on phenotype characters, although the G. dussii and G. subserpentina groups appear phenotypically intermediate. Species formerly placed in Hemithecium subg. Hemithecium sensu Staiger were shown to belong to at least four lineages, one nested within Graphis (H. implicatum), one within Allographa (H. chiorocarpum), one sister to Allographa (H. rufopallidum), and one nested within the Phaeographis dade (H. plicosum). Allographa is genetically close to the bulk of lirellate Graphidaceae (Diorygma, Glyphis, Pallidogranime, Phaeographis, Platygramme, Platythecium, Sarcographa, Thalloloma, Thecaria), whereas Graphis s.str. exhibits unique genetic apomorphies and takes a more isolated position. [ABSTRACT FROM AUTHOR]

Evolving a software process without a retrospective on its evolution and, in consequence, without an appropriate understanding, can lead to important problems for a software development organization. Two examples of such problems are inefficient performance as a consequence of the arbitrary introduction of changes or difficulty in demonstrating compliance to a given standard. Capturing information on the rationale underlying process changes provides a means for better understanding process evolution. This article presents two studies aimed at understanding and identifying information needs for describing the rationale for process evolution. Additionally, it presents an approach for incrementally evolving processes supported by this rationale. This approach is derived from the results of the studies and a survey of related work. An application of the approach during the evolution of a reference process for developing service-oriented applications is presented together with experience and open questions for future research work. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

To better understand the evolutionary history of the genus Artemisia (Anthemideae, Asteraceae) and its re- lationships to other genera of the subtribes Arternisiinae, Leucantheminae and Tanacetinae, 63 sequences of the external and 10 of the internal transcribed spacer of nuclear ribosomal DNA (ETS and ITS) were newly generated. Analyses were performed on the combined dataset using maximum parsimony, maximum likeli- hood and Bayesian inference. The combined analysis supports that all Artemisiinae genera included plus Hippolytia(subtribe Tanacetinae) and IVipponanthemum (subtribe Leucantheminae) constitute a monophyletic group. Within this group, a successive branching shows three monophyletic groups: (I) Nipponanthemumi Hippolylia/Brachanthemum; (2) the Dendranthema group; and (3) the Artemisia/Kaschgaria group. Within the latter, a new sister-group relationship is found between the monophyletic genus Kaschgaria and the Ar- temisia group, which comprises two main evolutionary lineages: (i) the Dracunculus dade including various Artemisia species and four Asian genera: Fil~foIium, Mausolea, Neopallasia and Turaniphytum; and (ii) the remaining subgenera of Artemisia plus the two North American genera: Picrothamnus and Sphaeromeria. Within this phylogenetic framework the evolution of two important characters (capitula and pollen type) in the group was inferred. Character reconstruction reveals that discoid capitula and Anihemis pollen type are the ancestral condition in the subtribe. The Artemisia/Kaschgaria lineage probably originated from an ances- tor with disciform capitula, central hermaphrodite florets and Artemisia pollen type. Molecular evidence of several biogeographical migration routes of the genus Artemisia is presented. [ABSTRACT FROM AUTHOR]

The parameter-free genetic algorithm (PfGA) is attracting interest as a new approach to avoiding the difficulty of parameter setting which has been a problem in genetic algorithms. However, there is a limit to the speed of evolution, since only random N-point crossover and mutation are used to modify the genes. On the other hand, various gene modification procedures have been attempted. Among these, there are some in which parameter setting is entirely or largely unnecessary. It may be useful to combine these with PfGA. This paper proposes a parameter-free genetic algorithm combined with the pseudo-simplex method, in an attempt to improve the power of optimal solution search by the pseudo-simplex method, which is known to be an effective method of improving the speed of genetic algorithms. The proposed algorithm uses the pseudo-simplex method in the process of generating the child individuals in the PfGA, and also in preprocessing to extract parent individuals from the subpopulation, in an attempt to improve the speed of evolution of the subpopulation. The proposed algorithm is compared to other methods in application to a function optimization problem, and it is verified that its performance for various types of functions is greatly superior to that of the ordinary PfGA, thus demonstrating its usefulness. © 2005 Wiley Periodicals, Inc. Syst Comp Jpn, 36(13): 35–44, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20311 [ABSTRACT FROM AUTHOR]

The phylogenetic relationships between actinolepids (Placodermi, Arthrodira) and other arthrodires (Phlyctaenii and Brachythoraci) are re-evaluated in connection with a study in progress on some Podolian and Spitsbergen actinolepid material. The species Kujdanowiaspis podolica (Brotzen, 1934) is briefly redescribed, and its characters discussed in relation to a recent cladistic analysis of the actinolepids. An enlarged phylogenetic analysis using a data matrix of 55 characters for 31 taxa reveals that the actinolepids may be a paraphyletic group; their taxonomic and nomenclatural status is briefly discussed. Within the actinolepids, the genus Kujdanowiaspis does not have the basal position proposed by previous authors. A proposed new phylogeny shows Wuttagoonaspis as the sister group to all other arthrodires, and the Phyllolepida as the sister group to the Phlyctaenioidei (Phlyctaenii plus Brachythoraci). [ABSTRACT FROM AUTHOR]

This paper reviews the scientific career of Rupert Riedl and his contributions to evolutionary biology. Rupert Riedl, a native of Vienna, Austria, began his career as a marine biologist who made important contributions to the systematics and anatomy of major invertebrate groups, as well as to marine ecology. When he assumed a professorship at the University of North Carolina in 1968, the predominant thinking in evolutionary biology focused on population genetics, to the virtual exclusion of most of the rest of biology. In this atmosphere Riedl developed his “systems theory” of evolution, which emphasizes the role of functional and developmental integration in limiting and enabling adaptive evolution by natural selection. The main objective of this theory is to account for the observed patterns of morphological evolution, such as the conservation of body plans. In contrast to other “alternative” theories of evolution, Riedl never denied the importance of natural selection as the driving force of evolution, but thought it necessary to contextualize natural selection with the organismal boundary conditions of adaptation. In Riedl's view development is the most important factor besides natural selection in shaping the pattern and processes of morphological evolution. J. Exp. Zool. (Mol. Dev. Evol.) 302B: 92-104, 2004. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Alexander Kowalevsky was one of the most significant 19th century biologists working at the intersection of evolution and embryology. The reinstatement of the Alexander Kowalevsky Medal by the St. Petersburg Society of Naturalists for outstanding contributions to understanding evolutionary relationships in the animal kingdom, evolutionary developmental biology, and comparative zoology is timely now that Evo-devo has emerged as a major research discipline in contemporary biology. Consideration of the intellectual lineage of comparative evolutionary embryology explicitly forces a reconsideration of some current conceptions of the modern emergence of Evo-devo, which has tended to exist in the shadow of experimental embryology throughout the 20th century, especially with respect to the recent success of developmental biology and developmental genetics. In particular we advocate a sharper distinction between the heritage of problems and the heritage of tools for contemporary Evo-devo. We provide brief overviews of the work of N. J. Berrill and D. T. Anderson to illustrate comparative evolutionary embryology in the 20th century, which provides an appropriate contextualization for a conceptual review of our research on the sea urchin genus Heliocidaris over the past two decades. We conclude that keeping research questions rather than experimental capabilities at the forefront of Evo-devo may be an antidote to any repeat of the stagnation experienced by the first group of evolutionary developmental biologists over one hundred years ago and acknowledges Kowalevsky's legacy in evolutionary embryology. J. Exp. Zool. (Mol Dev. Evol.) 302B:19–34, 2004. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

We discuss the interplay between evolution and development as reflected in data and concepts since about 1800. Darwin and his “continental apostle” Haeckel put the striking similarity between early vertebrate embryos in an evolutionary context. Haeckel's partly illicit generalizations discredited evolutionary thinking among early experimental embryologists who moreover noted riddles incompatible with contemporary concepts of homology and evolution. Relevant solutions were suggested by the more recent concept of ontogenetic networks that embody complex regulatory properties and genes with partly overlapping functions. Molecular data on development increasingly reveal evolutionary opportunism, for instance when a widespread signaling chain involved in primitive immune defense was apparently recruited later on for dorso-ventral axis determination in some evolutionarily advanced insect groups. Recently, Rickettsia-related bacteria colonizing many arthropod species were found to “manipulate” the first steps of host development to the advantage of their own propagation, but by ways that could also promote host speciation. Molecular genetics can now document evolutionary steps in ontogenetic networks. In the fruit fly for instance, the novel bicoid gene has superseded a crucial patterning function within a pre-existing network—a case of “molecular caenogenesis.” The expression patterns of conserved genes that antagonistically determine dorso-ventral polarity support a literal revolution envisioned almost 200 years ago. This is the dorso-ventral inversion of the body plan in some metazoans—ascribed then to the Articulata, now to the Chordata. The final section posits that the opportunistic character of evolutionary innovations is detrimental to parsimony in development. J. Exp. Zool. (Mol. Dev. Evol.) 302B:69–91, 2004. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The approach I have elected in this retrospective of how I became a student of evo-devo is both biographical and historical, a case study along the lines of Waddington's The Evolution of an Evolutionist ('75), although in my case it is the Evolution of an Evo-devoist. What were the major events that brought me to developmental biology and from there to evo-devo? They were, of course, specific to my generation, to the state of knowledge at the time, and to my own particular circumstances. Although exposed to evolution and embryology as an undergraduate in the 1960s, my PhD and post-PhD research programme lay within developmental biology until the early 1970s. An important formative influence on my studies as an undergraduate was the work of Conrad Hal Waddington (1905–1975), whose writings made me aware of genetic assimilation and gave me an epigenetic approach to my developmental studies. The switch to evo-devo (and my discovery of the existence of the neural crest), I owe to an ASZ (now SICB) symposium held in 1973. J. Exp. Zool. (Mol. Dev. Evol.) 302B:5–18, 2004. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Evidence is mounting that evolutionary change can occur rapidly and may be an important means by which species escape extinction in the face of global change. Consequently, biologists need to incorporate evolutionary thinking into management decisions in conservation and restoration ecology. Here, we review the genetic and demographic properties that influence the ability of populations to adapt to rapidly changing selective pressures. To illustrate how evolutionary thinking can influence conservation and restoration strategies, we compare the potential of two California plant communities (vernal pools and blue oak woodlands) to evolve in response to global change. We then suggest ways in which restoration biologists can manipulate the genetic architecture of target populations to increase their ability to adapt to changing conditions. While there may not be any universal rules regarding the adaptive potential of species, an understanding of the various processes involved in microevolution will increase the short- and long-term success of conservation and restoration efforts. [ABSTRACT FROM AUTHOR]

The article presents a study on implementing the concepts of evolutionary environment and reference conditions to ongoing ecological restoration projects in southwestern ponderosa pine (Pinus ponderosa Laws). It mentions that ecological restoration treatments are prepared to improve the recent, human-caused ecological degradation. It highlights that the suitable applications of restoration techniques will probably differ in various different kinds of settings.

The evolution of information technology has been characterized by three trends: increasing ethereality, increasing connectivity, and increasing versatility. As a consequence of these trends, the nature of many of the devices and systems with which people interact, in the workplace and elsewhere, has been changing rapidly and is likely to continue to do so in the future. In particular, devices are acquiring more and more cognitive-type capabilities and are being used to perform an increasingly large fraction of the tasks once done by human beings On the other hand, the increasing versatility of machines can expand greatly the universe of things that people can do with their help. Human factors researchers and engineers are concerned with the question of how to design tools, appliances, vehicles, communication devices and other artifacts so they are well matched to the capabilities and limitations of human beings and contribute positively to the safety, comfort, and productivity of their users, This concern will be at least as important in the future as it has been in the past, but the context in which it is exercised will be different in many respects. Reflection on how information technology may continue to evolve and be used raises many human factors issues and questions that need to be addressed. [ABSTRACT FROM AUTHOR]

Presents an excerpt from the book "The Monkey's Bridge: Mysteries of Evolution in Central America," by David Rains Wallace.

The article focuses on a study that claims of having genetic diversity in purple sea urchins to endure and adapt to ocean acidification. It states that sea urchins were collected from two distinct locations in which sea water have different carbon dioxide concentration of California coast. It mentions the result of the study that adaptation to climate change would lead to variation in heritable traits due to which there is chance of evolution of species to adopt to climate changes.

The article discusses the role of genes in the evolution of the ecosystem. According to recent research, the structure of the whole community of living organisms in which they survive, is driven by the genes of one dominant species. The evolution of the entire ecosystem is influenced by genetic variation, as in the case of cottonwood trees. The tannin levels in cottonwood trees was found to have predictable effects on the population density of diverse organisms . It is important to conserve genetic variation because of genetic interactions. The health and variability of populations can be influenced by the genetic variability within managed populations.

The article reflects on the proposition that alternative theories and evolution should be taught in equal weight in science classrooms. It defends the view that this proposition is unacceptable and does not achieve educational balance as asserted by its proponents. It views the actions of the Kansas Board of Education which altered its science standards to include supernatural explanations for observed phenomena as attempts to micromanage the dissemination of information and knowledge. It challenges the science community to make statements about science that will result in a sound and verifiable scientific knowledge as foundation to education, system of laws and government policies.