DARWINIAN WE ARE NOT: COUNTERFACTUALISM AS THE NATURAL COURSE OF HISTORY

This article considers Peter Bowler's recent contribution to the genre of counterfactual history as exemplifying a “restrained” counterfactual framework, one that must downplay the role of contingency in the historical process in order to present what Bowler calls a more “natural course” of historical development. This restrained counterfactual methodology is discussed with reference to analogous debates within evolutionary science about the competing roles of contingency and convergence in the history of life, along with recent work done within the humanities about the more subtle nuances of counterfactual reasoning. Although there is little doubt that Bowler's study will help legitimize the genre of counterfactual history, it is argued that the role of contingency—once thought to be integral to the counterfactual—has been necessarily minimized in order to construct a narrative that is a plausible counterfactual history of science. It is in this way that Bowler's world without Darwin sheds light on our historiographical preconceptions about what makes for a plausible historical narrative.     

Late Ordovician conodont biozonation of Australia—current status and regional biostratigraphic correlations

Zhen, Y.Y. & Percival, I.G. March 2017. Late Ordovician conodont biozonation of Australia—current status and regional biostratigraphic correlations. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

Seven conodont biozones are recognized in the Upper Ordovician of Australia. The Pygodus anserinus, Belodina compressa and Phragmodus undatus–Tasmanognathus careyi biozones are successively represented in the Sandbian. Although the Erismodus quadridactylus Biozone of the late Sandbian North America Midcontinent succession was previously recognized in the Stokes Siltstone of the Amadeus Basin and the Mithaka Formation of the Georgina Basin in central-north Australia, we argue for a middle–late Darriwilian age for these two units. Four conodont biozones, from oldest to youngest the Taoqupognathus philipi, T. blandus, T. tumidus–Protopanderodus insculptus and Aphelognathus grandis biozones, are established in the Katian of eastern Australia. Taoqupognathus species are particularly useful in correlation of the lower–middle Katian successions of eastern Australia with contemporary rocks in other parts of eastern Gondwana and peri-Gondwana, such as with the three major terranes of North and South China and Tarim. These regions, together with Sibumasu and eastern Australia, were part of the Australasian Superprovince during the Late Ordovician, with a strong palaeobiogeographic identity signalled by domination of Taoqupognathus, Tasmanognathus and Yaoxianognathus. Longstanding difficulties for precise correlation with the well-established North American Midcontinent or Baltoscandian successions in the Late Ordovician, owing mainly to strong endemism of the Australian faunas particularly from shallow-water settings, have been resolved by integration of regional conodont biostratigraphic schemes. The conodont biozonation of the Australian Upper Ordovician reviewed herein also provides a crucial chronological reference for better constraining the temporal and spatial range of Late Ordovician tectonostratigraphic events across the intracratonic basins of northern and western Australia and orogenic belts of eastern Australia.

Yong Yi Zhen* [yong-yi.zhen@industry.nsw.gov.au] and Ian G. Percival [ian.percival@industry.nsw.gov.au], Geological Survey of New South Wales, W.B. Clarke Geoscience Centre, 947–953 Londonderry Road, Londonderry NSW 2753, Australia.