A Survey of the Fossil Record for Dicotiledonous Wood and its Significance for Evolutionary and Ecological Wood Anatomy

Abstract

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.

A multi-proxy approach to determine Antarctic terrestrial palaeoclimate during the Late Cretaceous and Early Tertiary

“…This supports the conclusion drawn by Wheeler and Baas (1991). Therefore the use of growth characters in wood, often associated with general ecological variables, for climatic determination prior to the Tertiary may be confounded by the incomplete evolution of adaptational strategies.…”

“…Francis and Poole, 2002) but have used all the arcsine transformation formulae provided by Wiemann et al (1999) for comparative purposes. However it should be noted that the results obtained for the material dated as Coniacian-Campanian may be less precise since the evolution of some anatomical characters cannot (yet) be confirmed from the fossil record (Wheeler and Baas, 1991;E. Wheeler, personal communication).…”

“…Because this uncertainty exists, the data obtained from the fossil floras studied herein were plotted onto the original data set of Wiemann et al (1999) to determine whether the individual anatomical characters reveal trends in MAT of Antarctica over this time. The caveats outlined by Wheeler and Baas (1991) when using fossil angiosperm wood to interpret ecology still apply. Moreover since the appearance of the angiosperms in the southern high latitudes and their subsequent radiation is coupled with the demise of the gymnosperms (and Table 1 Climate variable formulae from Wiemann et al [1998b (Eqs. (1)- (5)) and 1999] [arcsine transformation Eqs.…”

“…Yet wood is often widespread and abundant throughout geological time, and coupled with its robust nature, can yield a potentially rich archive of palaeoecological and palaeoclimate data (Poole and van Bergen, in press). Wheeler and Baas (1991) highlight the considerable potential for using features of dicot woods as an additional tool in the study of palaeoclimates. However this approach was only realised when a better understanding was gained into the relationship between qualitative and quantitative wood anatomical data from modern wood and prevailing climate (Wiemann et al, 1998b).…”

Anatomia comparada do lenho de Copaifera langsdorffii Desf. (Leguminosae-Caesalpinoideae) de floresta e cerradão

“…Machado et al (1997) encontraram, para espécie do cerrado, Styrax camporum, placas de perfuração predominantemente simples nas raízes e escalariformes no caule e sugerem que este fato seja uma situação de adaptação às condições do ambiente. Wheeler & Baas (1991) consideram também que as placas de perfuração simples sejam mais eficientes quanto à demanda do intenso fluxo de água, imposta pelas altas taxas de transpiração, em regiões secas e quentes.…”