Abstract During the Global Taghanic Biocrisis ( c. 385 Ma), Middle Devonian faunas worldwide underwent extinction. In the biocrisis type region, the northern Appalachian Basin, biodiversity changes occurred through three bioevents that ultimately resulted in the loss of numerous endemic taxa. Carbon isotope excursions during this biocrisis have been documented in various stratigraphic successions, but never in the type region. Herein, we reconstruct changes in δ 13 C carb from the biocrisis type region and compare these changes to local faunal transitions. An approximately 1.5‰ negative excursion corresponds to the first bioevent, a time of inferred global warming and replacement of most endemic taxa of the mid-palaeolatitude Appalachian Basin by invasive palaeoequatorial taxa. An approximately 2‰ positive excursion is associated with the second bioevent, recognized as a return of the endemic fauna and the loss of invasive taxa. This positive excursion occurs near the Polygnathus ansatus–Ozarkodina semialternans zonal boundary and is recognized elsewhere. Faunal cosmopolitanism associated with the third bioevent corresponds with an inflection in the carbon isotope record from negative to positive trending values, which agrees with a positive carbon record excursion seen elsewhere at the semialternans – Schmidtognathus hermanni zonal boundary. This new carbon isotope record provides an important reference for recognizing this biocrisis in other areas and facies.

ABSTRACT The northern Rocky Mountain Trench of eastern British Columbia is a broad valley mantled by glaciolacustrine terraces supporting a complex mix of mesic-temperate (“interior wet belt”) forests that are strongly affected by terrain and substrate. Neither the geomorphic history during early Holocene deglaciation nor the vegetation history of the origin of the Tsuga heterophylla (western hemlock) and Thuja plicata (western redcedar) populations in the interior wet-belt forest is well understood. Sediment cores were obtained from two lakes, 10 km apart and occupying different terraces (83 m elevational difference), and these were compared to existing fire-history and paleoclimate reconstructions. Radiocarbon dates and a mapped terrain classification indicate the upper terrace formed as a lacustrine and glaciofluvial kame terrace hundreds of years prior to the lower terrace, which was formed by glaciolacustrine sediments of a proglacial lake. The minimum limiting ages of these terraces correlate with dated jökulhlaup deposits of the Fraser River. The upper site’s first detectable pollen at >11.0 ka was dominated by light-seeded pioneer taxa (Poaceae [grasses], Artemisia [sagebrush], and Populus [aspen]) followed by a peak in Pinus (pine) and finally dominance by Betula (birch) at 10.2 ka. Pollen data suggest an earlier invasion of T. heterophylla (western hemlock) (by ca. 8 ka) than previously understood. Wetlands on extensive, poorly drained, glaciolacustrine soils promoted the persistence of boreal taxa and open forests (e.g., Picea mariana [black spruce]), while the better-drained upper kame terrace promoted development of closed-canopy shade-tolerant taxa. Invasion and expansion of mesic cedar-hemlock taxa progressed since at least the middle Holocene but was highly constrained by edaphic controls.

Abstract The geological, faunal and palaeoecological conditions of the marine deposits from lowermost Eocene in North Jutland are briefly reviewed as background for the descriptions of six species of osteoglossiform fishes from the Stolle Klint Clay and the overlying Mo-clay (Ølst and Fur Formations respectively). Four of these primitive teleosteans are referred to new genera and species (one based on an almost complete skeleton, three others on skull material, one very incomplete), and the two most fragmentary specimens are referred to Brychaetus sp. and an indeterminate osteoglossiform. The phylogenetic relationships of these fossils are evaluated in the framework of two different models of osteoglossomorph phylogeny provided earlier by Taverne and Hilton. Despite differences in both data bases, methodologies and results given by the two models (the former based on c . 300 characters in an intuitive, qualitative phylogenetic parsimony analysis, the latter on 72 characters in a critical, rigorous, quantitative cladistic analysis) the phylogenetic positions of four of the fossil species are very similar in the two models concerning the relations to the recent forms. The other two species, rather fragmentary, but similar in many ways to the Eocene phareodonts (paraphyletic group), end up very differently in relation to extant forms in the two models. The phylogenetic systematics of all the marine, fossil osteoglossiforms (including Brychaetus, Opsithrissops and Monte Bolca forms) is evaluated as background for interpretation of their (palaeo-)biogeographic significance as marine members of a group, Osteoglossomorpha (of which the recent forms are prime examples of ‘primary division freshwater fishes’, and of which the extant osteoglossiforms have a classical ‘Gondwana distribution’. There are 9 marine, Eocene taxa (plus an otolith from the Maastrichtian of USA) and none of the 9 appear more closely-related to any other marine form in either model: they might constitute 9 separate migrations from freshwater into the sea. The phylogenetic results strongly suggest instead, that the extant osteoglossiforms have independently entered freshwater from the sea on two, perhaps even three occasions. This may have happened as late as the Eocene, and phareodonts could be yet another independent invasion of freshwater in the Late Cretaceous. The mormyriforms most likely had an independent invasion into freshwater (in one model even with notopterids as a separate migration from the sea by Mid or Early Cretaceous). Because all the closest outgroups of the Osteoglossomorpha are marine, the group obviously originated in the sea, probably by the Late Jurassic, and it is not impossible that Hiodontiforms in NE Asia and North America underwent another independent freshwater invasion very early in the Cretaceous. What then is wanting? The expected Cretaceous, marine osteoglossomorphs are not found (but note the above otolith).

ABSTRACT Museum collections provide a tremendous wealth of data bearing on biogeography, the field that focuses on the study of the distribution of organisms in space and time. Biogeography is a discipline that played a fundamental role in the development of ideas on evolution in the nineteenth century, and it still is a vibrant research area today. One way that biogeography has remained vibrant is through the burgeoning area of biodiversity science. There are many aspects of biodiversity science relevant to paleontology, running the gamut from conservation paleobiology to ecosystem observations, etc. Our especial focus here is on biodiversity science approaches involving the analysis of museum specimen records using mapping and analytical approaches, such as the geographic information system (GIS) and ecological niche modeling (ENM), to quantify how climate change has caused (and will continue to cause) species to move across the face of the globe through time. Initial efforts considered extant taxa, but now analyses of extinct taxa are becoming more commonplace. These analyses of fossil taxa offer extensive opportunities to gain increased insight into biogeography and also macroevolution. This contribution focuses specifically on approaches using fossil taxa and their associated museum specimen data. Such approaches have shown how invasive species have contributed to ancient biodiversity crises, how species niches largely remain stable over geological time scales, how it is predominately abiotic factors, as opposed to competition, that influence species distributions and determine species survival in the long term, and finally how extant species that have been present in marine ecosystems for millions of years are now in grave peril due to impending climate changes projected to occur in the near term. Each of these discoveries will be highlighted in order to help show the value that museum collections of fossils continue to have in the twenty-first century.

Abstract Preliminary biostratigraphic investigation of the Greenhorn Limestone at Pueblo, Colorado indicates that the Lincoln, Hartland, and lower Bridge Creek members are part of the Lithraphidites acutum calcareous nannofossil Zone. The middle and upper part of the Bridge Creek Member is assigned to the Quadrum gartneri Zone. Subdivision of these zones is difficult due to the scarcity of several biostratigraphically important taxa. Biohorizons based on secondary taxa do, however, offer promise for intrabasinal and intercontinental correlation. Paleobiogeographic analysis using three time-slices across the basin suggests that fresh-water influx from the basin margins was an important factor in restricting nannofossil occurrence and diversity during the initial stages of the invasion of oceanic surface water masses into the basin (middle Cenomanian). By maximum transgression, however, the effects of fresh-water influx appear to be minimal in the eastern and central portions of the basin.