Taxonomy, evolution and domestication of Vicia in relation to aphid resistance

Thirty Vicia species and 28 V. faba cultivars were evaluated for Aphis fabae resistance by measuring rates of aphid population increase (r_m) on the host plants. A subset of these species (22) and cultivars (five) were evaluated for resistance to Acyrthosiphon pisum and Megoura viciae. For the same subset of 22 Vicia species and all three aphid species, positive correlations were observed between the concentration and numbers of leaf and stem non-protein amino acids and the level of aphid resistance. Correlations were also observed between trichome density, on some organs of the host, and both nymphal survival and development time. Aphid resistance, together with these possible physical and chemical resistance mechanisms, showed a pattern which was described in relation to the taxonomy of the genus Vicia and the degree of domestication of the host. The least advanced Vicia species were most resistant whilst the more specialised species and those most closely related to V. faba and V. faba itself were most susceptible. Within each taxonomic group (subgenus or section), the most domesticated species were least resistant. The merits of utilising the resistance found in some V. faba cultivars and in other wild Vicia species were considered.     

Primary domestication and early uses of the emblematic olive tree: palaeobotanical, historical and molecular evidence from the Middle East

Our knowledge of the origins of olive tree domestication in the Middle East and on the processes governing its extension and persistence in different vegetation types from prehistory through antiquity to modern times derives from diverse sources, spanning the biological sciences to the humanities. Nonetheless, it lacks a robust overview that may lead to floating interpretations. This is especially true in the Middle East, considered as the cradle of agriculture, and where the evolutionary history of this emblematic tree is intertwined with that of civilizations. Olive fruit, oil and wood have been, since Prehistoric times, characteristic products of the lands bordering the Mediterranean Sea. In the domestic economy of these countries, the olive tree gradually became a traditional tree crop since the first oil extraction, through the emergence of regional commerce that accompanied the rise and fall of early Near-Middle Eastern urbanism, until the development of modern trade, with an oil production estimated at circa 3000000 tons per year. The rising importance of the olive tree in human life has turned the tree into an endless source of fascination in the Aegean and Eastern Mediterranean, a symbol and a sacred tree, widely cited in the Bibles, the Koran, and in ancient literature. Here we argue that advances in radiocarbon chronology, palaeobotany, genetics, and archaeology-history have profoundly refined the history of olive trees in the Middle East. This review shows that the heartland of primary olive domestication must be enlarged to the Levant and not only focus on the Jordan Valley. The domestication of the olive tree is a long and ongoing process, linked to the early production of oil and the development of the olive trade. We also suggest that the olive tree became a particular icon, a sacred tree, during the Biblical period in the Levant.     

History, current status and future of marine macroalgal research in New Zealand: Taxonomy, ecology, physiology and human uses

New Zealand has a rich and diverse macroalgal flora that has been studied since James Cook's first voyage to New Zealand in 1769. The New Zealand region ranges from cool temperate seas at southerly latitudes to subtropical waters in the north. Here we review the history of phycological research in New Zealand since 1900, and the current status of research in taxonomy, ecology, physiology and seaweed uses including aqua‐culture and seaweed extracts. Some 770 species of seaweed are known to New Zealand, of which 22 are alien. Few taxa have received monographic treatment and many remain to be described. Polysaccharides have been identified from over 80 New Zealand seaweeds and many of these compounds have commercial potential. In addition to urgent taxonomic work, future research should include a national program of long‐term (> 5 years) monitoring of macroalgal communities, rates of growth and primary production, and the contribution of seaweed‐based production to coastal food webs.     

家兔的起源驯化与育种

介绍了家兔起源及驯化的简要历史,现存主要家兔品种的分类,家兔与野兔的区别,世界主要养兔国家的兔业协会及育种和产业发展简况,并对家兔商业生产与宠物兔发展趋势作了展望。     

Taxonomy, phylogeny, and ecology of the heliobacteria

Heliobacteria are a recently discovered group of anoxygenic phototrophic bacteria, first described in 1983. Heliobacteria contain bacteriochlorophyll g, a pigment unique to species of this group, and synthesize the simplest photosynthetic complexes of all known phototrophs. Also, unlike all other phototrophs, heliobacteria lack a mechanism for autotrophy and produce endospores. Four genera of heliobacteria containing a total of 10 species are known. Species of the genera Heliobacterium, Heliobacillus, and Heliophilum grow best at neutral pH, whereas species of Heliorestis are alkaliphilic. Heliobacterium, Heliobacillus, and Heliophilum species form one phylogenetic clade of heliobacteria, while Heliorestis species form a second within the phylum Firmicutes of the domain Bacteria. Heliobacteria have a unique ecology, being primarily terrestrial rather than aquatic phototrophs, and may have evolved a mutualistic relationship with plants, in particular, rice plants. The genome sequence of the thermophile Heliobacterium modesticaldum supports the hypothesis that heliobacteria are “minimalist phototrophs” and that they may have played a key role in the evolution of phototrophic bacteria.     

Genetic analysis of wheat domestication and evolution under domestication

Wheat is undoubtedly one of the world's major food sources since the dawn of Near Eastern agriculture and up to the present day. Morphological, physiological, and genetic modifications involved in domestication and subsequent evolution under domestication were investigated in a tetraploid recombinant inbred line population, derived from a cross between durum wheat and its immediate progenitor wild emmer wheat. Experimental data were used to test previous assumptions regarding a protracted domestication process. The brittle rachis (Br) spike, thought to be a primary characteristic of domestication, was mapped to chromosome 2A as a single gene, suggesting, in light of previously reported Br loci (homoeologous group 3), a complex genetic model involved in spike brittleness. Twenty-seven quantitative trait loci (QTLs) conferring threshability and yield components (kernel size and number of kernels per spike) were mapped. The large number of QTLs detected in this and other studies suggests that following domestication, wheat evolutionary processes involved many genomic changes. The Br gene did not show either genetic (co-localization with QTLs) or phenotypic association with threshability or yield components, suggesting independence of the respective loci. It is argued here that changes in spike threshability and agronomic traits (e.g. yield and its components) are the outcome of plant evolution under domestication, rather than the result of a protracted domestication process. Revealing the genomic basis of wheat domestication and evolution under domestication, and clarifying their inter-relationships, will improve our understanding of wheat biology and contribute to further crop improvement.     

Molecular diversity, structure and domestication of grasses

Map-based cloning has been considered problematic for isolating quantitative trait loci (QTLs) due to the confounding phenotypic effects of environment and other QTLs. However, five recent studies, all in plants, have succeeded in cloning QTLs using map-based methods. We review the important features of these studies and evaluate the prospects for broader application of the techniques. Successful map-based cloning requires that QTLs represent single genes that can be isolated in near-isogenic lines, and that genotypes can be unambiguously inferred by progeny testing. In plants or animals for which map-based cloning of genes with discrete phenotypes is feasible, the modified procedures required for QTLs should not be limiting in most cases. The choice between map-based cloning and alternative methods will depend on details of the species and traits being studied.     

Taxonomy of the marine,luminous bacteria

Summary One hundred and seventy-three strains of marine, luminous bacteria isolated from sea water, surfaces and intestines of fish, as well as from the luminous organs of fish and squid were submitted to an extensive phenotypic characterization. A numerical analysis of the results grouped these strains into four clusters which were formed on the basis of overall phenotypic similarity. One cluster, which was given the designationBeneckea harveyi, consisted of strains which had a moles% GC content in their DNAs of 46.5±1.3 and a single, sheathed, polar flagellum when grown in liquid medium. Most of these strains had unsheathed, peritrichous flagella in addition to the sheathed, polar flagellum when grown on solid medium. The two phenotypically similar clusters which were assigned the species designationsPhotobacterium phosphoreum andP. mandapamensis consisted of strains which had 1–3 unsheathed, polar flagella and moles % GC contents in their DNAs of 41.5±0.7 and 42.9±0.5, respectively. The cluster designatedP. fischeri contained strains having 2–8 sheathed, polar flagella and a moles % GC content of 39.8±1.1. These four species could be further distinguished on the basis of a number of nutritional properties as well as other phenotypic traits. The assignment of the luminous, marine bacteria to four species was supported by differences in the properties of the luminous system as well as differences in the pattern of regulation of spartokinase activity which are discussed. The speciesB. harveyi was found to be phenotypically similar to a number of previously characterized, non-luminous strains ofBeneckea which should probably be assigned to this species.Non-Standard Abbreviations ASW artificial sea water - ATCC American Type Culture Collection - BM basal medium - BMA basal medium agar - GC guanine plus cytosine - LA luminous medium agar - LB luminous medium broth - MA Difco Marine Agar - NCMB National Collection of Marine Bacteria - PHB poly--hydroxybutyrate - S similarity coefficient - YEB yeast extract broth This paper is part of a dissertation submitted by the senior author to the Graduate Division of the University of Hawaii in partial fulfillment of the requirements for the Ph.D. Degree in Microbiology     

Taxonomy, slime molds, and the questions we ask

Taxonomic treatments often influence the way we both ask and attempt to answer certain biological questions. The classical taxonomy of the dictyostelid cellular slime molds (Dictyosteliales) involves a convenient set of categories that were developed independent of phylogeny. In order to test whether the characters supporting the classical taxonomy hold any phylogenetic signal, we subjected 19 described taxa belonging to two families (Acytosteliaceae and Dictyosteliaceae) and three genera (Acytostelium, Dictyostelium, and Polysphondylium) to rooted cladistic analyses using PAUP* v 4.0b4a. Neither family nor any of the three genera were found to represent monophyletic groups. These results confirm that the classical taxonomy used to delineate families and genera within these slime molds carries very little phylogenetic signal. Taxonomic character sets should be scrutinized phylogenetically in order to determine what information they provide about the relatedness of taxa within a group. Because taxonomy often drives the nature of biological inquiry, caution should be exercised when drawing conclusions regarding the evolution of developmental systems in Dictyostelium.     

Neo-Darwinism,niche construction theory,and the initial domestication of plants and animals

The initial domestication of plants and animals and the subsequent emergence of agricultural economies, which began independently more than 10,000 years ago in a number of different world regions, represent a major evolutionary transition in earth history. It is these domesticates, and the agricultural economies based on them, that have formed the lever with which humans have substantially modified the earth’s terrestrial ecosystems over the past ten millennia. General explanations for this transition from hunting and gathering to food production economies formulated over the past 40 years have been based on standard evolutionary theory (SET) and employ the assumption of unidirectional adaptation—that environments change and species adapt. Here I compare these proposed SET—based externalist explanations for domestication with a recently formulated alternative developed from niche construction theory (NCT). Archaeological and paleoenvironmental records from two independent centers of domestication in the Americas—eastern North America and the Neotropics of northern South America, are found to support the NCT-based explanatory approach but not the SET explanations, underscoring the limitations of externalist SET approaches and the need for broader conceptualization of the processes that direct evolutionary change in order to gain a better general understanding of initial domestication as well as other major evolutionary transitions.     

Systematics,Taxonomy, and the New Flora of the Bahamian Archipelago

A history of botanical exploration in the Bahama Archipelago is given, and is presented in three sections. The first section begins with the earliest botanical collections in 1700 by Thomas Walker and describes, in chronological order, botanical collections made up to 1920, when Britton and Millspaugh published the first Bahama flora. The second section chronicles botanical research in the archipelago after 1920, up until the publication by Correll and Correll of the Flora of the Bahama Archipelago in 1982. The third section describes plant research in the archipelago between 1982 and the present day. Following a brief rationale for the need for a new flora, the present research toward the flora is discussed, and an example of changes in the flora since 1982 is presented, with changes in the fern flora tabulated.     

Phytoplankton Evolution, Taxonomy and Ecology

This special issue is a collection of papers dedicated to GretaA. Fryxell by her students, colleagues and children, in honourof her long and distinguished career in the field of phytoplanktontaxonomy and ecology, especially the diatoms. The 21 papersin the book cover several different aspects ranging from taxonomy,ecology, morphology, physiology, toxin production, trophic modes,paleoecology and phylogeny. As expected from the focus of GAF'scareer, diatoms are the focus of most of these papers, whichprovide a wide picture of the state of the art in several     

Evolution and domestication of the Bovini species

Domestication of the Bovini species (taurine cattle, zebu, yak, river buffalo and swamp buffalo) since the early Holocene (ca. 10 000 BCE) has contributed significantly to the development of human civilization. In this study, we review recent literature on the origin and phylogeny, domestication and dispersal of the three major Bos species – taurine cattle, zebu and yak – and their genetic interactions. The global dispersion of taurine and zebu cattle was accompanied by population bottlenecks, which resulted in a marked phylogeographic differentiation of the mitochondrial and Y-chromosomal DNA. The high diversity of European breeds has been shaped through isolation-by-distance, different production objectives, breed formation and the expansion of popular breeds. The overlapping and broad ranges of taurine and zebu cattle led to hybridization with each other and with other bovine species. For instance, Chinese gayal carries zebu mitochondrial DNA; several Indonesian zebu descend from zebu bull × banteng cow crossings; Tibetan cattle and yak have exchanged gene variants; and about 5% of the American bison contain taurine mtDNA. Analysis at the genomic level indicates that introgression may have played a role in environmental adaptation.     

Self domestication and the evolution of language

We set out an account of how self-domestication plays a crucial role in the evolution of language. In doing so, we focus on the growing body of work that treats language structure as emerging from the process of cultural transmission. We argue that a full recognition of the importance of cultural transmission fundamentally changes the kind of questions we should be asking regarding the biological basis of language structure. If we think of language structure as reflecting an accumulated set of changes in our genome, then we might ask something like, “What are the genetic bases of language structure and why were they selected?” However, if cultural evolution can account for language structure, then this question no longer applies. Instead, we face the task of accounting for the origin of the traits that enabled that process of structure-creating cultural evolution to get started in the first place. In light of work on cultural evolution, then, the new question for biological evolution becomes, “How did those precursor traits evolve?” We identify two key precursor traits: (1) the transmission of the communication system through learning; and (2) the ability to infer the communicative intent associated with a signal or action. We then describe two comparative case studies—the Bengalese finch and the domestic dog—in which parallel traits can be seen emerging following domestication. Finally, we turn to the role of domestication in human evolution. We argue that the cultural evolution of language structure has its origin in an earlier process of self-domestication.     

Toward the domestication of lignocellulosic energy crops: learning from food crop domestication

Domestication of cereal crops has provided a stable source of food for thousands of years. The extent to which lignocellulosic crops will contribute to the world's renewable energy depends largely on how the new crops will be domesticated. Growing miscanthus as biofuel feedstocks on marginal and degraded land in northern and northwestern China offers an example for developing theoretical framework and practical strategies for energy crop domestication. The domestication should incorporate the highest possible genetic diversity from wild species, focus on the improvement of drought and cold tolerance especially in the stage of crop establishment, increase the efficiencies of water and nutrient uses and photosynthesis, adjust vegetative growing season according to local temperature and precipitation, and reduce or prevent seed production. Positive ecological effects on soil conservation, landscape restoration, carbon sequestration, and hydrological cycles should be maximized, while negative impact on biodiversity needs to be minimized. With the development of other sources of renewable energy, the role of lignocellulosic crops may evolve from primarily energy production to increasingly ecological restoration and biomaterial development. The integration of this new cropping system into the existing agriculture may open a new avenue to the long-term sustainability of our society.     

Taxonomy of the Cupressaceae: Subfamilies,Tribes and Genera

Cupressaceae and Taxodiaceae have recently been merged under the earlier name Cupressaceae s.I. by many authors, as the two families are similar in a number of morpho logical characters. Sciadopitys S. et Z., which has often been treated as a morphologically isolated member of the Taxodiaceae, has recently been considered as a monotypic family, Sciadopityaceae. The Cupressaceae s.s. may be reorganized into two subfamilies. The Cu pressoideae is composed of genera with the uppermost cone-scales infertile and can be divided into four tribes: Cnpresseae, including Cupressus, X Cupressocyparis, Charnaecyparis and Fokeinia;Thujopsideae, including Thuja, Thujopsis and Platycladusl Junipereae, including Juniperus and Microbiota; and Tetraclineae, including Calocedrus and Tetraclinis. The Callitroideae is composed of genera with the uppermost cone-scales fertile and can be divided into three tribes: Actinostrobeae, including Actinostrobus, Callitris, Fitzroya and Neocallitropsis; Widdringtoneae, including Pilgerodendron, Diselma and Widdringtonia ; Libocedreae, including Libocedrus, Papuacedrus and Austrocedrus. Five geographical distribution patterns are recognized in the 21 genera of Cupressaceae. (a) One genus, X Cupressocyparis, is a natural hybrid derived from selections in England; (b) Two genera, Cupressus and Juniperus, are distributed in Africa, Europe, Asia and North America; (c) Three genera, Thuja, Chamaecyparis, and Calocedrus, are disjnnctly distributed in Eastem Asia and North America; (d) Five genera, Actinostrobus, Callitris, Libocedrus, Papuacedrus and Widdringtonia, have limited distribution; and (e) The other 10 genera, which are monotypic, are restricted to narrow areas except Plotycladus. Three centers of genera diversity are identified in the Cupressaceae, i. e Eastern Asia with nine genera, southwestern North America with five genera, and Australia and its adjacent islands in the east　with six genera, including New Zealand,. Tasmania, New Caledonia, and New Guinea. Other important areas are western Mediterranean with three genera and Chile and Argentinawith three genera.