Taphonomy and Paleoecology of Fossil Insect Assemblages
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Document generated on 09/25/2021 12:55 a.m. Géographie physique et Quaternaire Taphonomy and Paleoecology of Fossil Insect Assemblages from Old Crow River (CRH-15) Northern Yukon Territory, Canada Taphonomie et paléoécologie d’associations d’insectes fossiles au site d’Old Crow River (CRH-15), nord du Yukon, Canada Taphonomie und Paleoökologie in fossilen Insekten Zusammensetzungen vom old Crow Fluss (Lokalität CRH-15), nördliches Yukon Territory, Kanada Richard E. Morlan and John V. Matthews Volume 37, Number 2, 1983 Article abstract The paleoenvironmental message delivered by any fossil assemblage is nearly URI: https://id.erudit.org/iderudit/032511ar always filtered to some degree by taphonomic and preservational biases. This DOI: https://doi.org/10.7202/032511ar paper discusses some of the types of biases that affect the composition of fossil Coleoptera (beetles) assemblages. Eight samples from a single site in the See table of contents northern Yukon provide the raw data for the analysis. They represent different types of host sediments — ranging from autochthonous peats to organic rich alluvial sands. For each assemblage the authors noted the state of preservation Publisher(s) of the fossils, counted the individual anatomical parts (pronota, heads, elytra) referred to each taxon and the number of articulated or partially articulated Les Presses de l'Université de Montréal specimens, and sorted the fossils on the basis of predefined ecological groups. The resulting data were then examined statistically, and compared with ISSN paleoenvironmental conclusions derived by examination of the present distribution of the taxa in each assemblage. The content of the insect 0705-7199 (print) assemblages varies with the type of host sediment. Insect fossils from 1492-143X (digital) autochthonous sediments deliver a reliable local environmental signal. Allochthonous sediments, such as alluvium, might be expected to contain Explore this journal fossils that provide an integrated picture of the regional environment, but in the Yukon such samples are seriously overrep resented by Lepidophorus lineaticollis, a weevil that lives on or near sandy floodplains. Deviations in the Cite this article representation of particular anatomical elements of L. lineaticollis from one sample to another warn of other more subtle taphonomic biases that may also Morlan, R. E. & Matthews, J. V. (1983). Taphonomy and Paleoecology of Fossil skew the content of northern fossil insect assemblages. Insect Assemblages from Old Crow River (CRH-15) Northern Yukon Territory, Canada. Géographie physique et Quaternaire, 37(2), 147–157. https://doi.org/10.7202/032511ar Tous droits réservés © Les Presses de l'Université de Montréal, 1983 This document is protected by copyright law. Use of the services of Érudit (including reproduction) is subject to its terms and conditions, which can be viewed online. https://apropos.erudit.org/en/users/policy-on-use/ This article is disseminated and preserved by Érudit. Érudit is a non-profit inter-university consortium of the Université de Montréal, Université Laval, and the Université du Québec à Montréal. Its mission is to promote and disseminate research. https://www.erudit.org/en/ Géographie physique et Quaternaire, 1983, vol. XXXVII, n° 2, p. 147-157, 2 fig., 3 tabl. TAPHONOMY AND PALEOECOLOGY OF FOSSIL INSECT ASSEMBLAGES FROM OLD CROW RIVER (CRH-15) NORTHERN YUKON TERRITORY, CANADA Richard E. MORLAN and John V. MATTHEWS, Jr., respectively, Archaeological Survey of Canada, National Museum of Man, Ottawa, Ontario K1A 0M8, and Terrain Sciences Division, Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A0E8. ABSTRACT The paleoenvironmental RÉSUMÉ Taphonomie et paléoécologie ZUSAMMENFASSUNG Taphonomie und message delivered by any fossil assem d'associations d'insectes fossiles au site Paleoôkologie in fossilen Insekten Zusam- blage is nearly always filtered to some d'Old Crow River (CRH-15), nord du mensetzungen vom old Crow Fluss degree by taphonomic and preser- Yukon, Canada. Le message paléoenvi (Lokalitàt CRH - 15), nôrdliches Yukon vational biases. This paper discusses ronnemental transmis par toute associa Territory, Kanada.Die paleo-ôkologische some of the types of biases that affect tion de fossiles est presque toujours plus Botschaft, die uns durch jede fossile the composition of fossil Coleoptera ou moins dénaturé par des facteurs liés Zusammensetzung gegeben wird, ist (beetles) assemblages. Eight samples à la taphonomie et à la préservation. Le fast immer bis zu einem gewissen Grade from a single site in the northern Yukon rapport présente certaines catégories de durch taphonomische und Preservier- provide the raw data for the analysis. facteurs qui influent sur la composition ungs Tendenzen gefiltert. Dieser Artikel They represent different types of host des associations de coléoptères fos behandelt einige der typischen Verfor- sediments — ranging from autoch siles. Les données brutes sont tirées de mungen welche die Komposition von thonous peats to organic rich alluvial huit échantillons provenant d'un seul fossilen Coleopters (Kàfer) Zusammen- sands. For each assemblage the authors emplacement dans le nord du Yukon. setzungen angehen. Acht Proben von noted the state of preservation of the Ces échantillons représentent divers einem einzigen Forschungssitz im nord- fossils, counted the individual anatomic types de sédiments encaissants. Pour lichen Yukon, ergeben die Daten fur die al parts (pronota, heads, elytra) referred chaque association, on a noté l'état de Analyse. Sie reprâsentieren verschiedene to each taxon and the number of ar préservation des fossiles, compté le Typen von Wirts-Sedimenten. Fur jede ticulated or partially articulated speci nombre de parties anatomiques (pronota, Zusammensetzung haben die Autoren mens, and sorted the fossils on the basis têtes, élytres) par taxon et le nombre den Erhaltungszustand der Fossile of predefined ecological groups. The d'échantillons articulés ou partiellement vermerkt, die individuellen anatomischen resulting data were then examined articulés, et trié les fossiles selon des Teile gezâhlt (Pronota, Kôpfe, Elytra) in statistically, and compared with paleo groupes écologiques prédéterminés. Les Bezug auf jedes Taxon und die Zahl der environmental conclusions derived by données ont été étudiées statistiquement, artikulierten oder teilweise artikulierten examination of the present distribution puis comparées aux conclusions paléo Specimen, und haben die Fossile nach of the taxa in each assemblage. The environnementales tirées de l'étude de predefinierten ôkologischen Gruppen content of the insect assemblages varies la répartition actuelle des taxons dans sortiert. Der Inhalt der Insekten Zusam- with the type of host sediment. Insect chaque association. Le contenu des mensetzungen veràndert sich je nach fossils from autochthonous sediments associations d'insectes varie en fonction dem Typ des Wirts-Sedimentes. Insekten- deliver a reliable local environmental du type de sédiment encaissant. Les fossile aus einheimischen Sedimenten signal. Allochthonous sediments, such insectes fossiles dans les sédiments ergeben ein sicheres, ôrtliches ôkologis- as alluvium, might be expected to con autochtones fournissent des données ches Signal. Vom Inhalt der allochtonen tain fossils that provide an integrated fiables sur l'environnement local. Les Sedimente, wie Alluvium, môge man picture of the regional environment, but sédiments allochtones comme les allu einen Gehalt an Fossilen die ein Gesamt- in the Yukon such samples are seriously vions devraient contenir des fossiles qui bild der regionalen Umgebung ergibt, overrep resented by Lepidophorus donneraient une image intégrée de erwarten aber im Yukon sind solche lineaticollis, a weevil that lives on or near l'environnement régional; toutefois, au Proben sehr beeinflusst durch die Ge- sandy floodplains. Deviations in the Yukon, ces échantillons sont gravement genwart von Lepidophorus lineaticollis. representation of particular anatomical surreprésentés par le Lepidophorus Abweichungen in der Vertretung von elements of L lineaticollis from one lineaticollis. Les écarts dans la repré speziellen anatomischen Elementen von sample to another warn of other more sentation des éléments anatomiques L. lineaticollis von einer Probe zur subtle taphonomic biases that may also particuliers de L. lineaticollis dans les anderen, warnen vor anderen, mehr skew the content of northern fossil divers échantillons avertissent le cher subtilen taphonomischen Tendenzen. die insect assemblages. cheur de l'existence d'autres facteurs auch den Inhalt von nôrdlichen Fossil taphonomiques plus subtils qui pour Insekt Zusammensetzungen beeinflussen raient modifier le contenu des associa kônnen. tions d'insectes fossiles dans le Nord. 148 R. E. MORLAN and J. V. MATTHEWS, Jr. INTRODUCTION For the past six years a group of workers from the Geological Survey of Canada, University of Alberta, and the National Museums of Canada, has co-operated in the Yukon Refugium Project, a geological, paleo- ecological and archaeological study of the northern Yukon part of the Beringian refugium. Summary papers describing the general and detailed findings at a number of sites are now published or in preparation (HUGHES et al., 1981 ). The Old Crow Basin has been the focus of most of this research, and one site in particular, CRH-15 (67°51.5'N; 139C48'W.), also known informally as Old Crow River Location 15, has received more de tailed study than