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New Characters (new + character)
Selected AbstractsComparative morphology of the leaf epidermis in Schisandra (Schisandraceae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2005ZHI-RONG YANG The leaf epidermis of 127 samples representing ten species within Schisandra Michaux. and one species of the related genus, Kadsura Kaempf. ex Juss., was investigated using light and scanning electron microscopy. Many characters of the leaf epidermis in Schisandra, such as pattern of epidermal cells, type of stomata, shape of guard cell pairs and cuticular ornamentation, are usually constant within species and thus make good characters for studying the relationship between and within genera. A new character, rim number, of the outer stomatal rim in the genus is introduced. It is shown that double outer stomatal rims occur only in evergreen Schisandra species, whereas a single rim occurs in deciduous species. This character supports the classification of Schisandra into two subgenera based on habit and androecial organs. This classification is also supported by additional morphological and molecular taxonomic characters. Kadsura coccinea (Lem.) Smith A. C. is the most primitive taxon in the related genus Kadsura. The outer stomatal rim of this species also has double rims. Combined with morphological and molecular evidence, this suggests that Schisandra and Kadsura are closely related and may share a recent common ancestor. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 148, 39,56. [source] Searching for new morphological characters in the systematics of scleractinian reef corals: comparison of septal teeth and granules between Atlantic and Pacific MussidaeACTA ZOOLOGICA, Issue 2 2009Ann F. Budd Abstract Recent molecular analyses have challenged the traditional classification of scleractinian corals at all taxonomic levels suggesting that new morphological characters are needed. Here we tackle this problem for the family Mussidae, which is polyphyletic. Most of its members belong to two molecular clades composed of: (1) Atlantic Mussidae and Faviidae (except Montastraea) and (2) Pacific Mussidae (Cynarina, Lobophyllia, Scolymia, Symphyllia) and Pectiniidae. Other Pacific mussids (e.g. Acanthastrea) belong to additional clades. To discover new characters that would better serve as phylogenetic markers, we compare the skeletal morphology of mussid genera in different molecular-based clades. Three sets of characters are considered: (1) macromorphology (budding; colony form; size and shape of corallites; numbers of septal cycles), (2) micromorphology (shapes and distributions of septal teeth and granules), and (3) microstructure (arrangement of calcification centres and thickening deposits within costosepta). Although most traditional macromorphological characters exhibit homoplasy, several new micromorphological characters are effective at distinguishing clades, including the shapes and distribution of septal teeth and granules, the area between teeth, and the development of thickening deposits. Arrangements of calcification centres and fibres differ among clades, but the fine-scale structure of thickening deposits does not. [source] Phylogenetic comparison of spicule networks in cryptobranchiate dorid nudibranchs (Gastropoda, Euthyneura, Nudibranchia, Doridina)ACTA ZOOLOGICA, Issue 4 2008Brian K. Penney Abstract Many dorid nudibranchs possess large numbers of calcareous spicules in their mantle, gill, rhinophores and foot. However, the arrangements of these structures and their differences among taxa are poorly known. Spicule networks were stained with Alizarin red and compared among 12 species of cryptobranchiate dorid nudibranchs and four outgroups. Three general types of networks were found: a cobweb-like, unbraced framework of one or few spicules per side; a ramifying system of thick, spiculated tracts; and a lattice-like arrangement of distinct radial and circumferential tracts. The Discodorididae species investigated shared a cobweb-like network and papillae supported by a ring of spicules, while the Porostomata showed consistent characters leading to a lattice-like network with larger spicules in the central notum. The Dorididae studied were not cohesive, but each species shared characters with the aforementioned groups. Therefore, spicule network form may provide new characters to help resolve the phylogeny of Doridina. [source] COGNITIVE AND BEHAVIORAL MODEL ENSEMBLES FOR AUTONOMOUS VIRTUAL CHARACTERSCOMPUTATIONAL INTELLIGENCE, Issue 2 2010Jeffrey S. Whiting Cognitive and behavioral models have become popular methods for creating autonomous self-animating characters. Creating these models present the following challenges: (1) creating a cognitive or behavioral model is a time-intensive and complex process that must be done by an expert programmer and (2) the models are created to solve a specific problem in a given environment and because of their specific nature cannot be easily reused. Combining existing models together would allow an animator, without the need for a programmer, to create new characters in less time and to leverage each model's strengths, resulting in an increase in the character's performance and in the creation of new behaviors and animations. This article provides a framework that can aggregate existing behavioral and cognitive models into an ensemble. An animator has only to rate how appropriately a character performs in a set of scenarios and the system then uses machine learning to determine how the character should act given the current situation. Empirical results from multiple case studies validate the approach. 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