Marine sessile benthos living on hard substrates have evolved a variety of attachment strategies. Rhizotrochus (Scleractinia, Flabellidae) is a representative of azooxanthellate solitary scleractinians with a wide geographical distribution and unique attachment structures; it firmly attaches to hard substrates using numerous tube-like rootlets, which are extended from a corallum wall. In contrast, most sessile corals, whether extant or extinct, are attached by stereome-reinforced structures at their corallum bases. However, morphological and constructional traits of the rootlets themselves, along with their evolutionary significance, have not yet been fully resolved. Growth and developmental processes of spines in Truncatoflabellum and rootlets in Rhizotrochus suggest that these attachment structures are homologous. Both structures commonly develop from the calicular edges of walls through the transformation of wall structures, and their skeletal microstructures exhibit similar patterns of rapid accretion and thickening deposits. Taking molecular phylogeny and fossil records of flabellids into consideration, Rhizotrochus evolved from a common free-living ancestor and invaded hard-substrate habitats by the exploitation of rootlets originating from spines, which were adaptive for soft-substrates. Repeated evolution of attachment apparatuses in both scleractinian Rhizotrochus and extinct rugosans (e.g., Silurian Dokophyllum) is likely to represent evolutionary convergence. This study of attachment strategies in Rhizotrochus provides new insights into the understanding of not only the history of adaptive strategies of sessile benthos on changing substrates, but also the natures of soft tissues in extinct organisms.

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Candida aurisは2009年に我が国において患者の外耳道から分離・報告された新しいカンジダの一種である。多くの菌株で高い環境生残性・抗真菌薬耐性傾向を示し，商業ベースの検査方法では診断できないという特徴がある。そのため，真菌では初めてとなる汎世界的流行を引き起こし，世界40か国，6つの地域で検出報告がある。すでに500近い論文が発表され，そのうちいくつかではout breakも報告されている¹⁾。急速な世界的拡大，多剤耐性による高い死亡率を持つことから，2016年Centers for Disease control and Prevention（CDC）はC. aurisを「薬剤耐性脅威レポート」においてurgent threats（もっとも優先度の高い脅威）に位置付け，警告をしている。ここ10年で世界的脅威となりつつある，C. aurisについて概説する。

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集団中のヘデロな遺伝子座の機会的固定が阻止され,集団中にヘテロ性が保持される幾つかの場合について考察した.
(1) 孤立した単一集団ならば,世代の経過とともにその有効な大きさが指数的に増大する場合,あるいは単一集団が周囲から個体の移入を毎代受け入れでいる場合がそれであるが,人間が繁殖を支配できる家畜においては,
(2) 幾つかの近交系に対する交配を巡回的に行なつて,生産家畜群を維持する場合には,近交系における近親交配がいかに強度であつても,生産家畜群においては,極限状態でも,ヘテロ性は消失しない.たとえば,近交系が3個以上であれば,近交係数は10%以下に保たれることが明らかになつた.

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The family relationships among a sample of members drawn from a particular generation of populations or species play a central role in describing the genealogical behaviour of generations of individuals. Such a genealogical approach is certainly interesting and important in its own right, but it is also very useful to produce a wide variety of classical results in the mathematical theory of population genetics. The power and elegance of the theory rely on 'equivalence' or 'exchangeability' among individuals in a population and have been best demonstrated in single-locus multiple-allele systems. Here I would like to introduce the basic idea of the theory and some results of its application to molecular taxonomy.

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本稿では古生物学という学問と，絶滅した中生代の化石海生爬虫類である首長竜について解説した．化石の研究は古生物学と呼ばれ，考古学と間違われやすいが，地学と生物学の境界に位置しており，博物館との関わりも深い．古生物学に関連するトピックは小学校から高等学校までの様々な学年の理科教科書に登場し，高校教科書では地学と生物学の両方にまたがっている．

首長竜は恐竜であると思われがちであるが，系統学的な定義でも骨の形態でも異なる別個の分類群である．また，福島県で発見された首長竜フタバスズキリュウを用いて，学名や記載論文の意義についても解説した．

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　ベイズ法に基づいた分岐年代推定ソフトウェアーを用いて，ウイルスの年代推定が最近盛んに行われている．筆者は世界中から3種の代表的な植物ウイルスを独自に採集し，それらのゲノム塩基配列情報を決定後，ウイルスの拡散経路が農業史や人類移動にどのように関連しているのか，時間軸（タイムスケール）について解析した．農業が開始する以前の世界では雑草などにウイルスが潜んでいたと思われるが，現在は食用作物，特用作物，牧草・芝草，草花，果樹そして野菜と様々な農作物に感染し，現代の人類生存に大きな影響を及ぼしている．野菜は食料として重要であるが，中でも大きな割合を占めるのがアブラナ科の野菜である．多くのアブラナ科植物の起源は地中海沿岸地方を含んだヨーロッパ南部や小・中央アジアと言われている．アブラナ科の野菜に大きな被害を与えている代表的な3種のウイルス，ポティウイルス科ポティウイルス属のカブモザイクウイルス，カリモウイルス科カリモウイルス属のカリフラワーモザイクウイルスそしてブロモウイルス科ククモウイルス属のキュウリモザイクウイルスを取り上げ，植物ウイルス分子進化に纏わる時間軸に関連した新しい知見を解説する．

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Many students of Korean kinship have observed that there is an organization of close agnates, called tang-nae or chib-an, a "group" of patrilineal descendants of a common great-great-grandfather. This "group" it has been pointed out, is closely related to the institutions of ancestor cults and five mourning grades. The present paper is an analysis of this "group" based on the field data from a village m South Cholla province. (There are three kinds of ancestor cults in Korea, tomb cult-shihyangche-and two kinds of home cults-ch'arye and kije. We are concerned here with the home cults only.) A man has an obligation to perform memorial services for his patri-lineal ancestors within four generations. The services are performed at the house of the eldest son of the deceased. The status of the eldest son as the chief priest in offering memorial services is transmitted to his eldest son in turn at his death. Thus, the households (chip) of a set of brothers are differentiated into the one of the eldest brother, where the memorial services for their parents are performed, and those of the younger brothers. The former is called k'un-chip (big house), and the latter, chagun-chip (small house) . The range of male agnates who share a common great-great-grandfather (the highest generation ancestor for whom the memorial services are offered at home) is called tang-nae, or more commonly chib-an. Usually the terms k'un-chip and chagun-chip are used within the range of tang-nae or chib-an. Since tang-nae consists of the male patrilineal descendants of a common fourth generation ancestor and their spouses, only those of the same generation within the third cousin range patrilaterally have the same range of tang-nae. Thus, theoretically, the constitution of tang-nae differs with each generation. Though the Confucian teachings obligate only the lineal descendants to perform memorial services for the ancestors, there is a consensus that it is a matter of courtesy to attend the services for the collateral ancestors performed at the households of one's chib-an, too. On the other hand, those lineal descendants who live away from the village where the k'un-chip is located (where the services are offered) tend to skip the memorial services especially when the services are for the remoter generation ancestors. Thus, the services are actually performed by a portion of lineal descendants and a portion of collateral descendants roughly within the range of tang-nae. It is imperative that a man, once married, should be offered services after death and that his line should be perpetuated in the genealogy (chokpo) . Adoption is resorted to when a man has no son. The adoptee should be of the same lineage in the first descending generation of the adopting person. There is a preference for close kin relationship between the parties before an arrangement of adoption is made. The adopted son succeeds his adoptive father for ritual purposes, and he inherits the property of the latter. More often than not, however, adoption is arranged after the death of the adopting person, and in such cases, no radical change may be made in the arrangements of life of the adoptee, except for the ritual purposes. Adoption brings about a situation where the formal genealogical relationships expressed in chokpo and those relationships by birth do not coincide with each other. Under such circumstances, the chib-an relationships are determined by the relationships by birth, and not by those of chokpo genealogy.

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Higher-level relationships of the basal teleosts are reviewed, with particular reference to the monophyly and interrelationships of the Elopomorpha.Since Greenwood et al. established in 1966 the Elopomorpha on the basis of eight putative synapomorphies, many authors have discussed validity of their monophyly through comparative observations of osteology, ontogeny, microstructure of spermatozoa, and physiology. Such circumstantial evidence have remained controversial, because none of them have reconstructed their phylogeny using character matrices derived from both morphological and molecular data. The same is true of long-standing controversy over phylogenetic positions of the Elopomorpha among major basal teleostean lineages, many authors simply demonstrating their “views” in the form of cladograms with putative synapomorphies until quite recently. Considering their morphological heterogeneity (from very primitive elopomorphs to highly derived eels) and ancient origins that presumably goes back to over a hundred million years ago, we concluded that corroboration of monophyly and determination of the phylogenetic position of the Elopomorpha should be based on comparisons of longer DNA sequences from many purposefully-chosen species. Recent development of a PCR-based approach for sequencing the fish mitochondrial genomes would be the most promising candidate for providing such data within a short period of time and they have actually resolved the latter problem in a recent study.

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