Geoffrey T. Creber's research while affiliated with Birkbeck, University of London and other places

Publications (14)

Article
Summary1. The wood of trees grown in temperate regions shows a periodicity in the form of rings which, with certain known exceptions, accurately reflects the annual cycle of the seasons. The wood thus has a built-in dating system.2. Tree rings are not always the same width in successive years; the widths show a positive correlation with variations...
Article
SUMMARY Specimens of Woodworthia arizonica Jeffrey trees from the Late Triassic of Arizona, U.S.A. and the Permian of Brazil, typically have horizontal vascular traces that have extremely close contacts with the tracheids of the secondary xylem. In modern gymnospermous and angiospermous trees, such traces terminate on preventitious buds deeply embe...
Article
Two fossil tree species, both with unusual characteristics, occur in the Upper Triassic of the Petrified Forest National Park, Arizona, USA and adjacent areas. The first, Schilderia adamanica, has a highly idiosyncratic secondary xylem structure which contains normal uniseriate and broad complex multiseriate ‘herring-bone’ rays. The trunk cross-sec...
Article
Examination and measurement of many of the trunks attributed to Araucarioxylon arizonicum Knowlton eroded from the Late Triassic Chinle Formation in the Petrified Forest National Park, Arizona demonstrate that the living tree did not closely resemble any of the present-day Araucaria trees of the southern hemisphere as postulated in past reconstruct...
Article
Typically, the fossil woods in the Upper Triassic Chinle Formation in Petrified Forest National Park, Arizona, USA do not show annual growth rings but contain irregular growth interruptions similar to those found in trees now growing in the humid tropics. These interruptions could be due to endogenous hormonal effects or to occasional local variati...
Article
Certain Upper Triassic tree trunks in the southwestern U.S.A. show evidence of damage similar to that caused in tree trunks at the present day by pocket rot fungi such as Polyporus amarus Hedgc. and Heterobasidion annosum (Fries) Bref. The damaged trunks occur in a relatively thin stratum at the same horizon over a wide area in the Petrified Forest...
Article
The agreement in the pattern of major biomes with that of climatic zonation of the Earth gives a strong indication that climate is the overriding influence controlling the distribution of plant communities. Three aspects of plants which may be preserved in the fossil state, give a signal of the climatic conditions under which they grew: (1) the pre...
Chapter
The solar energy input into the very high southern latitudes determines the maximum productivity level that could have been achièyed by Antarctic ecosystems in the geological past when there was not a major glaciation. The input of energy must supply all that is needed the primary producers (the green plants) to carry out photosynthesis.Finally, th...
Article
The existence of a temperate Antarctic flora in the Permian, Mesozoic and early Tertiary poses a number of problems that are not soluble by reference to any environmental situation obtaining at the present day (i.e. in which plants live in a regime where a warm summer is followed by a winter without sunlight). Certain characteristics of the polar c...
Article
Fossil plant records from a late Carboniferous to early Permian time interval are reviewed for the data that they give on connections and migration routes between floristic provinces, and their palaeolatitudinal positions. Caution is urged in using fragmentary leaf remains as a basis for recognizing affinity between floristic provinces, as illustra...
Article
Evidence from the distribution and characteristics of fossil wood in the Mesozoic and Early Tertiary indicates that a much warmer global climate prevailed in those times. There appears to have been a broad zone of largely non-seasonal climate stretching from about 32° N to 32° S (palaeolatitudes). In addition to this low-latitude zone, forest growt...
Article
The mechanism of wood development records in varying degree the effects of both external and internal factors that are operating at the time of development. As a result, fossil woods spanning the last 370 million years represent a unique palaeo-environmental data-store. Data concerning external factors that can be reclaimed consist of: presence or...

Citations

... The MS has been used by several authors for paleoclimatic analysis (e.g., Creber & Chaloner, 1984;Francis & Poole, 2002;Brea et al., 2011;Pires & Guerra-Sommer, 2011). MS values are higher than 0.3 in Nothofagoxylon scalariforme (Tab. ...
... During the Permian, the warming of the global climate from icehouse to extreme hothouse conditions allowed trees to colonize high latitudes and establish forests well beyond the polar circle (Taylor et al. 2000;Cantrill & Poole 2012). Fossils from these regions yield insights into the diversity and biology of the trees growing in these ecosystems with no modern analogue, that is warm polar forests with a strongly seasonal light regime (Creber 1990;Francis 1994;Taylor & Ryberg 2007;Gulbranson et al. 2014;Slater et al. 2015;Miller et al. 2016). In the Late Permian, the high-latitude forests of the Southern Hemisphere were largely dominated by trees belonging to an extinct order of seed plants, the Glossopteridales (Cúneo et al. 1993;Anderson et al. 1999;Taylor et al. 2009). ...
... Bill continued to work on wood growth rings. Creber and Chaloner (1987) compared trees of Late Devonian and Carboniferous age with younger wood from the latest Paleozoic, Mesozoic and Paleogene. The former were shown either to have no growth rings, or to exhibit very weakly developed ones, and hence largely grew in low palaeolatitudes with an inferred virtually seasonless climate. ...
... Decay patterns consistent with white rot and white pocket rot have been observed in Glossopteris root wood (Vertebraria) and stem wood (Australoxylon) from the Permian of Antarctica (Stubblefield and Taylor, 1986;Weaver et al., 1997;Harper et al. 2017), and in Araucarioxylon wood from Triassic strata of the same region (Stubblefield and Taylor, 1986). The symptoms of wood-rotting fungi have also been described from numerous trunks of Late Triassic trees from the Petrified Forest of Arizona (Chinle Formation; Creber and Ash, 1990). Erasmus (1976, figs 1, 7) also illustrated, but did not describe, white and soft rots in an araucarian wood from the Cretaceous of Natal. ...
... By contrast, younger rock units contain woods from trees which grew at high polar latitudes with relatively equable temperatures and high seasonality and which were shown to possess clear growth rings. In greenhouse intervals, tree growth is possible at the poles because the light availability, despite its seasonality, is perfectly adequate for vigorous tree growth (Chaloner and Creber 1989). The significance of tree rings was also discussed in two general accounts of the use of fossil plants as proxies for palaeoclimate Chaloner 1994). ...
... Plant distribution during the Carboniferous varied in space as well as time and several geographical floristic units (phytochoria) have been distinguished (e.g. Chaloner and Lacey 1973;Chaloner and Meyen 1973;Vakhrameev et al. 1978;Rowley et al. 1985;Meyen 1987;Allen and Dineley 1988;Chaloner and Creber 1988;Thomas 1991, 2019;Wnuk 1996;Cleal 2020). However, the degree of floristic provincialism changed dramatically during this time period as the global climatic changes resulting from the developing Late Paleozoic Ice Age took effect. ...
... Conifers are hypothesized to be crucial components on the Late Triassic terrestrial ecosystems in northern Xinjiang. Growth rings in fossil woods have been widely used to assess palaeoenvironmental conditions prevailing during the tree growth (Chaloner and Creber, 1973, 1988, 1990Creber and Chaloner, 1985;Wan et al., 2020a). In Megaporoxylon sinensis sp. ...
... The warm climate with a mean annual temperature of 15° (Herman and Spicer, 1996), allowed plants to flourish in the high palaeo-latitude (>60°), even under conditions of elevated CO 2 and long dark winters (Creber and Chaloner, 1984;Chaloner and Creber, 1990;Vakhrameev, 1991;Spicer et al., 2002). ...
... Several reports of vegetative reproduction in fossil gymnosperms have been published, including epicormic resprouting and production of root shoots. Epicormic resprouting has been recorded in Woodworthia [26,27], Glossopterids [28], Araucaria mirabilis [29], Cuyoxylon [30], a new tree taxon [31] and an unspecified conifer genus [32]. Root suckering has been recorded in Notophyllum krauselii [33,34] and Austrocupressinoxylon barcinense [35]. ...
... This is particularly relevant because present vegetation at high latitudes (above 60 • ) is uncommon (particularly in the southern land masses), illustrating paleoecological and paleoclimatological shifts in the colonization of land through Earth history. Low/middle latitude studies of fossil forest exist, especially involving Paleozoic examples (Cúneoand Andreis, 1983;Gastaldo, 1986;DiMichele et al., 2007, to summarize a few of them), Mesozoic (McKnight et al., 1990;Keller and Hendrix, 1997;Roberts and Hendrix, 2000;Ash and Creber, 2000;Lehman and Wheeler, 2001;Artabe et al., 2007;Brea et al., 2008;Falaschi et al., 2011) and Cenozoic sites (Mosbruggeret al., 1994). Most of these studies have provided an enormous amount of data that help our understanding of tree communities, in particular lycopods in the Paleozoic, and conifers and to lesser degree angiosperms in the Mesozoic and Cenozoic. ...