The last interglacial-glacial transition in North America

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  • JOURNAL OF QUATERNARY SCIENCE (1 996) 11 (2) 167-1 72 0 1996 by John Wiley & Sons, Ltd.

    Book Reviews

    The last interglacial-glacial transition in North America Edited by P. U. CLARK and P. D. LEA Publisher The Geological Society of America, Special Paper 270, Boulder, Co 1992 (317 pp) ISBN 0-8137-2270-5 f37.50

    This volume derives from a symposium on the subject (taken to be 122-64 ka) held by the Geological Society of America in 1988. A few years delay in publication i s not unusual in such cases; note that most of the papers here were accepted in 1991. The delay has not affected the interest and useful- ness of the contributions, which cover the highly important matter of the change from the last interglacial to last glacial in the region dominated by the Laurentide ice-sheet and the Cordilleran ice-sheet. Considering the predominance of the Laurentide ice-sheet in contributing to global effects, such as, inter alia, sea-level fluctuations and the marine isotope ice volume signal, any student of these matters will have to take into account the facts described herein.

    The contributions include an outline review of the period in North America, a historical review of Early Wisconsin glaciation (by R. P. Goldthwait, the doyen of North American glacial geology, to whom the volume is dedicated), matters of wide significance such as the marine isotope record, U- series dating of coastal sediments and ice-sheet initiation in relation to Milankovitch and global climate models, and finally reviews of the transition (glacial geology, stratigraphy, palaeontology, pedology) in significant areas, including the Canadian Arctic, areas across the glaciated region of Canada and the USA, the Cordillera and as far south as New Mexico. The reviews of the much-studied and classic sequences in Illinois and the Toronto area, for example, will be welcomed.

    All the papers are extensive and valuable reviews, well- illustrated. They bring to mind especially the problems that face those attempting to link global changes to marine, coastal and continental sequences, and the absolute necess- ity for a reliable geochronology, often not available with the required accuracy. The discussions underline the difficulties of relating orbital forcing to ice-sheet growth in Oxygen Isotope Stage 5. There is evidence that the expansion of the northern margin of the Laurentide ice-sheet to its maximum extent took place during stage 5, whereas the southern mar- gin reached its maximum in stage2, although showing growth in stages 5 and 4. These matters are compared with data from the mountain glaciers and pluvial lakes of the west of the USA, where some ranges show evidence of Early Wisconsin maxima and others Later Wisconsin, differences that may relate to local climatic or hypsometric effects.

    To have a survey of a continent in this way makes this volume an essential read for serious friends of the Pleisto- cene, and, with its reasonable price, it should be in all libraries that cater for Quaternary researchers.

    R. G. WEST Godwin institute for Quaternary Research

    Botany School Downing Street

    cambridge CB2 3EA England

    Morphological change in Quaternary mammals of North America Edited by ROBERT A. MARTIN and ANTHONY D. BARNOSKY

    Publisher Cambridge University Press, Cambridge, MA. 1993 (415 pp)

    The book presents a compendium of 16 papers presented at the symposium entitled Morphological Change in Quaternary Mammals of North America, held at Berry College, 9-10 April 1991. The papers present interesting examples of mor- phological changes in, mainly North American, mammals, but more importantly they review the present state of knowl- edge of the evolution of (Quaternary) mammals and provide interesting theoretical ideas about evolutionary processes.

    The first, introductory, contribution Quaternary mammals and evolutionary theory: introductory remarks and historical perspective, written by the editors, gives a clear explanation of the aims of the symposium as well as their proceedings, including the terminology used in the volume as well as a review of evolutionary models, patterns and processes. The book presents not only case studies but also theoretical and methodological contributions, for example the papers A method for recognizing morphological stasis, written by Deborah K. Anderson, Variogram analysis of paleontological data, by Andrew P. Czebieniak, and a paper by Viriot et a/. in which they describe not only the ontogenetic change of muskrat (Ondatra zibethicus) cheek teeth but also intro- duce image processing techniques for analysing these kinds of changes.

    The case studies presented in the volume cover changes from the short, ontogenetic time-scale to changes occurring over millions of years (e.g. Adrian M. Lister, Evolution of mammoth and moose: the Holarctic perspective; Larry D. Martin, Evolution of hypsodonty and enamel structure in Plio-Pleistocene rodents). A number of the contributions clearly show that the study of morphological changes during the Pleistocene is very much hampered by the chronological resolution of our present dating methods for the time-range beyond l00000yr ago. Our knowledge may be good enough to use fossil mammals for biostratigraphical purposes, but the occurrence of complex mosaic patterns of episodic phyletic evolution (as reported by Robert A. Martin: Variation

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