• The Journal of the Korea Contents Association
• /
• v.14 no.1
• /
• pp.66-75
• /
• 2014

The purpose of this study is to analyze and illustrate 'Rhizome', a postmodern speculation system based on de-subjectivity and decentralization, presented by Gilles Deleuze. He borrowed the word rhizome, an originally botanical term meaning a horizontal stem under the surface of the earth, to counteract the dominating system grounded on binary, root-tree structure. The study then criticizes the early movements of de-subjectivity with molecular-biological and evolutionary evidences, and proves that these evidences can only be characterized by chance and nomadism, which are the key elements that constitute Rhizome. As a practical example of Rhizome, the study analyzes the film by Gus Van Sant, and demonstrates that both his various cinematic experiments and the result bear the same characteristics as Rhizome.

• Animal Systematics, Evolution and Diversity
• /
• v.17 no.2
• /
• pp.263-275
• /
• 2001

Animal phyla in the traditional animal phylogeny were organized into an order of increasing body plan complexity, which was based on the similarities in early embryonic stages. Molecular phylogeny mainly by 18S rRNA data provides recently re-evaluation of the traditional evolutionary scenario. The current molecular-based view of animal relationships strongly suggest the burst of two groups regraded as intermediate grades of body complexity in the traditional concept and displacement of them into higher positions in the tree. The new animal tree provides a framework within new picture of bilaterian ancestor could be drawn, and comparative developmental and genomic data to be interpreted.

• The Bulletin of The Korean Astronomical Society
• /
• v.39 no.1
• /
• pp.33.2-33.2
• /
• 2014

Halo merger trees are essential backbones of semi-analytic models for galaxy formation and evolution. Recent studies have pointed out that extracting merger trees from numerical simulations of structure formation is non-trivial; different algorithm can give differing merger histories. Thus they should be carefully understood before being used as input for models of galaxy formation. As one of the projects proposed in the SUSSING MERGER TREES Workshop, we investigate the impact of different halo merger trees on a semi-analytic model. We find that the z = 0 global galaxy properties in our model show differences between trees when using a common parameter set, but that these differences are not very significant. However, the star formation history of the Universe and the properties of satellite galaxies can show marked differences between trees with different methods for constructing a tree. Calibrating the SAM for each tree individually to the empirical data can reduce the discrepancies between the z = 0 global galaxy properties, however this is at cost of increasing the differences in evolutionary histories of galaxies. Furthermore, the underlying physics implied can vary, resulting in key quantities such as the supernova feedback efficiency differing by factors of 2. Such a change alters the regimes where star formation is primarily suppressed by supernovae. Therefore, halo merger trees extracted from a common halo catalogue using different, but reliable, algorithms can result in a difference in the semi-analytic model, however, given the enormous uncertainties in galaxy formation physics, these are not necessarily significant.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2023.04a
• /
• pp.11-11
• /
• 2023

Due to the abundance of information in Nuclear DNA, it has a magnificent phylogenetic resolution. Moreover, because they show biparental inheritance, it has proven to be superior to organelle DNA, which has a limited number of genes and only shows maternal lineage. In particular, the transcriptome, which includes much nuclear DNA but is relatively inexpensive to analyze, can provide valuable insights into evolution through selection analysis and enable gene function research. This study's dataset includes 45 transcriptomes (16 generated for this study). It aims to explore the evolutionary history of Apioideae by comparing the results of the phylogenetic analysis with gene tree discordance and chloroplast phylogeny. The results confirmed the taxonomic positions of Peucedanum terebinthaceum, Ligusticum tachiroei, and Cymopterus melanotilingia and proposed a genus change for Glehnia littoralis. High gene tree discordances were identified in recently diverged clades, suggesting frequent hybridization and introgression. In the most recently diverged tribe of Selineae, the highest number of PSGs (positively selected genes) has been confirmed, which is inferred to be due to the geological and climatic diversity of their originated habitat, Central Asia. These genes include those related to responses to growth and drought, oxidative, and salt stress. In particular, the CYP97A gene confirmed as PSGs in Bupleurum latissimum is inferred to be a result of adaptation to the light-limited environment of Ulleungdo Island, as it is associated with the efficiency of photosynthesis.

• Korean Journal of Plant Taxonomy
• /
• v.40 no.1
• /
• pp.1-15
• /
• 2010

Recognizing a basal group in a taxon is one of the most important factors involved in understanding the evolutionary history of that group of life. Many botanists have suggested a sister to all other angiosperms to understand the origin and rapid diversification of angiosperms based on morphological and fossil evidence. Recent technical advances in molecular biology and the accumulation of molecular phylogenetic data have provided evidence of the extant basal-most angiosperm which is a sister to all other angiosperms. Although it is still arguable, most plant taxonomists agree that Amborella trichopoda Baill., a species (monotypic genus and monotypic family) distributed in New Caledonia, is a sister to all other extant angiosperms based on evidence from the following molecular approaches: 1) classical phylogenetic analyses based on multiple genes (or DNA regions), 2) analyses of a tree network of duplicated gene families, and 3) gene-structural evidence. As an alternative hypothesis with relatively minor evidence, some researchers have also suggested that Amborella and Nymphaeaceae form a clade that is a sister to all other angiosperms. Debate regarding the basal-most angiosperms is still ongoing and is currently one of the hot issues in plant evolutionary biology. We expect that sequencing of the whole genome of Amborella as an evolutionary model plant and subsequent studies based on this genome sequence will provide information regarding the origin and rapid diversification of angiosperms, which is Darwin's so called abominable mystery.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.35 no.1
• /
• pp.1-8
• /
• 2011

An analytical study on the flow resistance of tree-shaped channel-flow architectures was carried out based on the principle of the constructal law; the evolutionary increase in the access to currents that flow through the channels with improvements in the flow configurations were studied in a square domain using two diameters. Two types of tree-shaped configurations were optimized. The minimized global flow resistance decreased steadily as the system size $N^2$ increased. From the two channel configurations, the one that resulted in better pressure drop was selected. Further, it was shown that the system performance can be enhanced by adopting the second tree-shaped configurations when the system size is greater than $18^2$.

• Journal of Ecology and Environment
• /
• v.41 no.8
• /
• pp.223-234
• /
• 2017

Background: Spatial structure of plants in a population reflects complex interactions of ecological and evolutionary processes. For dioecious plants, differences in reproduction cost between sexes and sizes might affect their spatial distribution. Abiotic heterogeneity may also affect adaptation activities, and result in a unique spatial structure of the population. Thus, we examined sex- and size-related spatial distributions of old-growth forest of dioecious tree Torreya nucifera in extremely heterogeneous Gotjawal terrain of Jeju Island, South Korea. Methods: We generated a database of location, sex, and size (DBH) of T. nucifera trees for each quadrat ($160{\times}300m$) in each of the three sites previously defined (quadrat A, B, C in Site I, II, and III, respectively). T. nucifera trees were categorized into eight groups based on sex (males vs. females), size (small vs. large trees), and sex by size (small vs. large males, and small vs. large females) for spatial point pattern analysis. Univariate and bivariate spatial analyses were conducted. Results: Univariate spatial analysis showed that spatial patterns of T. nucifera trees differed among the three quadrats. In quadrat A, individual trees showed random distribution at all scales regardless of sex and size groups. When assessing univariate patterns for sex by size groups in quadrat B, small males and small females were distributed randomly at all scales whereas large males and large females were clumped. All groups in quadrat C were clustered at short distances but the pattern changed as distance was increased. Bivariate spatial analyses testing the association between sex and size groups showed that spatial segregation occurred only in quadrat C. Males and females were spatially independent at all scales. However, after controlling for size, males and females were spatially separated. Conclusions: Diverse spatial patterns of T. nucifera trees across the three sites within the Torreya Forest imply that adaptive explanations are not sufficient for understanding spatial structure in this old-growth forest. If so, the role of Gotjawal terrain in terms of creating extremely diverse microhabitats and subsequently stochastic processes of survival and mortality of trees, both of which ultimately determine spatial patterns, needs to be further examined.

• Journal of Microbiology and Biotechnology
• /
• v.6 no.5
• /
• pp.364-365
• /
• 1996

A region encoding the 16S rRNA was cloned by PCR from Streptomyces melanosporofaciens 7489 and sequenced by the chain-termination dideoxy sequencing method. A phylogenetic tree constructed by sequence alignment of 24 Streptomyces species suggests that there is little evolutionary distance between this strain and Streptomyces rimosus.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.1
• /
• pp.23-27
• /
• 2008

Self-splicing group I introns in tRNA anticodon loops have been found in diverse groups of bacteria. In this work, we identified $tRNA^{fMet}$ group I introns in six strains of marine Synechococcus elongatus. Introns with sizes around 280 bp were consistently obtained in all the strains tested. In a phylogenetic analysis using the nucleotide sequence determined in this study with other cyanobacterial $tRNA^{fMet}$ and $tRNA^{Leu}$ intron sequences, the Synechococcus sequence was grouped together with the sequences from other unicellular cyanobacterial strains. Interestingly, the phylogenetic tree inferred from the intronic sequences clearly separates the different tRNA introns, suggesting that each family has its own evolutionary history.

• Journal of Species Research
• /
• v.10 no.2
• /
• pp.142-153
• /
• 2021

Algal genomics approaches provide a massive number of genome/transcriptome sequences and reveal the evolutionary history vis-à-vis primary and serial endosymbiosis events that contributed to the biodiversity of photosynthetic eukaryotes in the eukaryote tree of life. In particular, phylogenomic methods using several hundred or thousands of genes have provided new insights into algal taxonomy and systematics. Using this method, many novel insights into algal species diversity and systematics occurred, leading to taxonomic revisions. In addition, horizontal gene transfers (HGTs) of functional genes have been identified in algal genomes that played essential roles in environmental adaptation and genomic diversification. Finally, algal genomics data can be used to address the pangenome, including core genes shared among all isolates and partially shared strain-specific genes. However, some aspects of the pangenome concept (genome variability of intraspecies level) conflict with population genomics concepts, and the issue is closely related to defining species boundaries using genome variability. This review suggests a desirable future direction to merge algal pangenomics and population genomics beyond traditional molecular phylogeny and taxonomy.