Data on fossil dicotyledonous wood were assembled in order to 1) test the Baileyan model for trends of specialisation in dicotyledonous wood anatomy by addressing the question - were 'primitive' wood anatomieal features (as defined by the Baileyan model) more common in the geologie past than at present?, 2) infer, on a broad geographie scale, past climatie regimes, and long term climatic change, and 3) assess the extent of knowledge of fossil dicotyledonous woods. The resulting database has information on 91 anatomieal features for over 1200 fossil dicotyledonous woods. The incidence of selected anatomical features was plotted through time (by geologie epoch) for the world and for two regional groupings (roughly corresponding to the Laurasian and Gondwanan supercontinents). For comparison to the fossil wood record, the incidence of wood anatomie al features in the Recent flora was obtained from the 5260 record OPCN database for extant dicotyledonous woods.

Information from the Inside Wood database (5,663 descriptions) was used to determine the relative abundance of selected IAWA Hardwood List Features, for the whole world and for the broad geographic regions used in the IAWA List. Features that occur in more than 75 % of the records are: growth ring boundaries indistinct or absent, diffuse porosity, exclusively simple perforation plates, alternate intervessel pitting, and non-septate fibers. The geographic distribution of vessel element features found in this study is consistent with previous studies: ring porosity is a Northern Hemisphere adaptation; numerous, narrow, short vessel elements are more common in temperate regions than in tropical regions. Element size is related to habit, with few wide vessels being a syndrome that is virtually absent from shrubs and small trees. The co-occurrence of selected features, ones that earlier have been suggested to be correlated, was examined; e.g., tangential vessel arrangement and ring porosity, rare axial parenchyma and septate fibers, tracheids and exclusively solitary vessels that are of medium to wide diameter. Axial parenchyma features show geographic variation, with aliform to confluent parenchyma and bands more than 3 cells wide being primarily tropical in occurrence. Storied rays, crystals, and silica bodies are more common in the tropics than in the temperate Northern Hemisphere. For ray features, geographic patterns are less apparent. In Australia, incidences of some features (vestured pits, solitary vessels, radial/diagonal vessel arrangement) are influenced by the Myrtaceae being a major component of the flora. This paper is but a general overview. Information from the Inside Wood database when combined with detailed information on ecological and geographical distributions of species, and subjected to more robust statistical analyses can be used to address a variety of questions on the evolution of wood structure and the ecological and phylogenetic significance of suites of features.

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Ecological trends for occurrence of certain vessel, tracheid and fibre characteristics. have been analysed for 505 species (belonging to 221 genera and 71 families) from Europe, Cyprus, and Madeira. Macroclimatic gradients from boreal, via temperate to mediterranean are strongly related with a decreasing incidence of scalariform perforations, (almost) exclusively solitary vessels, and fibre-tracheids (i. e., fibres with distinctly bordered pits). In this sequence the incidence of different vessel size classes (vessel dimorphism) and vascular tracheids increases. Ring-porous tendencies and spiral vessei thickenings have their peaks in the temperate zone. The subtropical flora of Madeira shows low values for the percentage of species with any of the above attributes.

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Bordered pits play an important role in permitting water flow among adjacent tracheary elements in flowering plants. Variation in the bordered pit structure is suggested to be adaptive in optimally balancing the conflict between hydraulic efficiency (conductivity) and safety from air entry at the pit membrane (air seeding). The possible function of vestured pits, which are bordered pits with protuberances from the secondary cell wall of the pit chamber, could be increased hydraulic resistance or minimized vulnerability to air seeding. These functional hypotheses have to be harmonized with the notion that the vestured or nonvestured nature of pits contains strong phylogenetic signals (i.e., often characterize large species-rich clades with broad ecological ranges). A literature survey of 11,843 species covering 6,428 genera from diverse climates indicates that the incidence of vestured pits considerably decreases from tropics to tundra. The highest frequencies of vestured pits occur in deserts and tropical seasonal woodlands. Moreover, a distinctly developed network of branched vestures is mainly restricted to warm habitats in both mesic and dry (sub)tropical lowlands, whereas vestures in woody plants from cold and boreal arctic environments are usually minute and simple. A similar survey of the frequency of exclusively scalariform perforation plates illustrates that the major ecological trend of this feature is opposite that of vestured pits. These findings provide previously undescribed insights suggesting that vessels with vestured pits and simple perforation plates function as an efficient hydraulic system in plants growing in warm environments with periodical or continuous drought stress.B otanists have long speculated on the mutual relationship between the structure and function of different wood anatomical features and how ecological conditions correlate with xylem features (1-4). The evolution of xylem vessels has been considered a key adaptation marking the pinnacle of hydraulic efficiency in flowering plants, because plants with vessels generally have higher hydraulic conductivities than plants that rely solely on tracheids for water transport (5). The traditional view is that evolutionary trends of vessel elements have been regarded as reliable tools in the study of angiosperm phylogeny, because vessel characters were considered conservative traits containing a wealth of potentially significant systematic information (2, 6, 7). Although parallel development of vessel characters is generally accepted, recent phylogenetic analyses of angiosperms suggest there have also been some reversals in the Baileyan transformation series (8, 9). Therefore, parallel evolution and reversibility in vessel characters imply a strong adaptive significance of xylem hydraulic architecture.The structure of bordered intervessel pits, which are small openings where the secondary cell wall was not deposited over the primary wall (Figs. 1 and 2 A), permits water flow between adjacent vessels, but pits are also a weak link in pro...

To say it briefly, this is a marvellous book. It describes in depth and richly illustrates the wood structure of some 180 trade timbers belonging to approximately 60 families. This edition in the English language finally allows access for non-Japanese scientists, wood engineers and applicants of wood to the lifetime work of Ken Ogata, one of the foremost wood anatomists of our time. Contrary to gloomy predictions that by the year 2000 world timber trade would be largely restricted to plantation-grown pines and eucalypts and products manufactured thereof, the diversity of tropical timbers shipped to the main importing countries, such as China, Japan and EU countries, has actually increased. This is a constant challenge for those involved in wood identification. Representatives of wood industry and trade are the traditional and still the most important customers for this service. But on the other hand, also archaeologists, architects, paleobotanists, and, more recently, agencies responsible for monitoring and controlling trade with protected plants and activities concerning illegal logging are also seeking help and advice from wood anatomists responsible for timber identification. And this is what this book addresses.From A (Alangiaceae) to V (Verbenaceae), each hardwood timber description gives a brief explanation of the botanical and trade nomenclature and the geographical distribution of a trade timber, followed by concise description of macroscopic and microscopic features. Nearly all comments are accompanied by accurate line drawings highlighting structural patterns and specific features. Moreover, a series of excellent half-tone illustrations cover a wide range of magnifications on macroscopic, microscopic and SEM level and explain structural features of the woods in question. In addition,