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Upper Paleozoic sedimentary rocks form outliers delineated by large strike-slip faults in the Blacks HarbourBeaver Harbour area in southwestern New Brunswick. Currently included in the Upper Devonian Perry Formation, and Visean-Pennsylvanian Mabou Group (Balls Lake Formation) and Cumberland Group (Lancaster Formation), these units have been subject to varied interpretations since the initial mapping during the 19th century. The Perry Formation, a red bed sequence consisting of coarse conglomerate, sandstone, minor shale, and mafic volcanic rocks, has yielded plant fossils (indeterminate debris and decorticated stem and root fossils) considered to be broadly Devonian, and most likely Famennian. The 'Carboniferous' strata have proven more intractable. Three units have been defined by mapping: Lighthouse Cove Formation (previously: 'Fish Plant Beds'), Cripps Steam Formation, and Russels Point Formation (previously: 'Beaver Harbour Formation'). These units have yielded plant fossils in the form of indeterminate debris and decorticated stem and root fragments that various workers have attributed to the Silurian, Devonian, Mississippian, or Pennsylvanian. New palynological analyses from the Perry Formation (at Tunaville) and Russels Point Formation (at Woodland Cove and Russels Point) have yielded stratigraphically significant assemblages. The Tunaville assemblage, the first miospores from anywhere in the Perry Formation, and roughly in the middle of the local sequence, is lower to middle Famennian. Two miospore assemblages are from near the base of the Russels Point Formation: one shows a possible range from Tournaisian to Holkerian (middle Visean), and the second is better constrained between Chadian and Holkerian (lower to middle Visean). Only the Lighthouse Cove Formation ('Fish Plant Beds') failed to yield any miospore assemblages; however, mapping and structural considerations are compatible with this unit being older than the Russels Point Formation and younger than the Perry Formation and most likely Tournaisian to lower Visean. One new stratigraphic relationship has been located along the southern shore of Deadmans Harbour where an angular unconformity occurs between red beds of the Perry Formation and grey beds of the overlying Russels Point Formation. Contrasting deformation styles in these units related to displacement on the Belleisle Fault constrain a major phase of strike-slip movement to the Famennian-Tournaisian interval. Des roches s dimentaires du Pal ozo que sup rieur forment des enclaves d limit es par de vaste failles d crochantes dans le secteur de Blacks Harbour-Beaver dans le sud-ouest du Nouveau-Brunswick. Ces unit s, actuellement incluses dans la Formation du D vonien sup rieur de Perry, le groupe vis en-pennsylvanien de Mabou (Formation de Balls Lake) et le groupe de Cumberland (Formation de Lancaster), ont fait l'objet de diverses interpr tations depuis leur cartographie initiale au cours du [19.sup.e] si cle. La Formation de Perry, une s quence de couches rouges constitu e d'un conglom rat grossier, de gr s, de schiste modeste et de roches volcanomafiques, a livr des fossiles v g taux (d bris ind termin s et fossiles de tiges et racines d cortiqu es) consid r s comme des vestiges remontant d'une fa on g n rale au D vonien, et tr s probablement au Famennien. Les strates << carbonif res >> se sont av r es plus insolubles. Trois unit s ont t d finies dans le cadre de travaux cartographiques: la formation de Lighthouse Cove (pr c demment << les couches de l'usine de traitement du poisson >>), la Formation de Cripps Steam et la Formation de Russels Point, (pr c demment << la Formation de Beaver Harbour >>). Les unit s en question ont livr des fossiles v g taux sous forme de d bris ind termin s et de fragments de tiges et racines d cortiqu es que divers chercheurs ont attribu s au Silurien, au D vonien, au Mississippien ou au Pennsylvanien. De nouvelles analyses palynologiques de la Formation Perry ( Tunaville) et de la Formation de Russels Point (dans l'anse Woodland et sur la pointe Russels) ont fourni des assemblages strat giquement significatifs. L'assemblage de Tunaville, premiers miospores relev s l'int rieur de la Formation Perry, qui sont pr sents vers le milieu de la s quence, sont du Famennien inf rieur moyen. Deux assemblages de miospores se trouvent pr s de la base de la Formation de Russels Point: l'un affiche une fourchette possible du Tournaisien l'Holk rien (Vis en moyen) et le second se limite de fa on plus pr cise entre le Tchadien et l'Holk rien (du Vis en inf rieur moyen). Seule la Formation de Lighthouse Cove (<< couches de l'usine de traitement du poisson >>) n'a pas pr sent d'assemblages de miospores, mais les consid rations cartographiques et structurales pertinentes sont compatibles avec un ge de l'unit sup rieur celui de la Formation de Russels Point et inf rieur celui de la Formation Perry, correspondant vraisemblablement la p riode du Tournaisien au Vis en inf rieur. Un nouveau lien stratigraphique a t d couvert le long du rivage sud de Deadmans Harbour l'endroit o une discordance angulaire s'inscrit entre les couches rouges de la Formation Perry et les couches grises de la Formation sus-jacente de Russels Point. Les modes oppos s de d formation dans ces unit s li s au d placement sur la faille de Belleisle restreignent une phase d terminante du coulissage l'intervalle du Famennien au Tournaisien. [Traduit par la redaction], INTRODUCTION Upper Paleozoic sedimentary rocks form outliers adjacent to the Belleisle Fault, a major orogen-parallel strike-slip fault within the northern Appalachian orogenic collage in the Blacks Harbour to Beaver Harbour [...]

Sirenians, such as manatees and dugongs, are herbivorous marine mammals commonly called sea cows with a fossil record extending from middle Eocene deposits to the present (Domning 2001). An extinct, [...]

Author(s): Blake V. Dickson [sup.1] , Jennifer A. Clack [sup.2] , Timothy R. Smithson [sup.2] , Stephanie E. Pierce [sup.1] Author Affiliations: (1) Museum of Comparative Zoology, Department of Organismic [...], The acquisition of terrestrial, limb-based locomotion during tetrapod evolution has remained a subject of debate for more than a century.sup.1,2. Our current understanding of the locomotor transition from water to land is largely based on a few exemplar fossils such as Tiktaalik.sup.3, Acanthostega.sup.4, Ichthyostega.sup.5 and Pederpes.sup.6. However, isolated bony elements may reveal hidden functional diversity, providing a more comprehensive evolutionary perspective.sup.7. Here we analyse 40 three-dimensionally preserved humeri from extinct tetrapodomorphs that span the fin-to-limb transition and use functionally informed ecological adaptive landscapes.sup.8-10 to reconstruct the evolution of terrestrial locomotion. We show that evolutionary changes in the shape of the humerus are driven by ecology and phylogeny and are associated with functional trade-offs related to locomotor performance. Two divergent adaptive landscapes are recovered for aquatic fishes and terrestrial crown tetrapods, each of which is defined by a different combination of functional specializations. Humeri of stem tetrapods share a unique suite of functional adaptations, but do not conform to their own predicted adaptive peak. Instead, humeri of stem tetrapods fall at the base of the crown tetrapod landscape, indicating that the capacity for terrestrial locomotion occurred with the origin of limbs. Our results suggest that stem tetrapods may have used transitional gaits.sup.5,11 during the initial stages of land exploration, stabilized by the opposing selective pressures of their amphibious habits. Effective limb-based locomotion did not arise until loss of the ancestral &apos;L-shaped&apos; humerus in the crown group, setting the stage for the diversification of terrestrial tetrapods and the establishment of modern ecological niches.sup.12,13. Analysis of humeri from fossils that span the fin-to-limb transition reveal that the change in the humerus shape is driven by both ecology and phylogeny, and is associated with functional trade-offs related to locomotor performance.

Crinoids (Phylum Echinodermata) represent major components of fossil assemblages in the type Cincinnatian (Upper Ordovician: Katian) of the greater Cincinnati Arch region. However, certain shallow marine lithofacies are characterized by a nonexistent to depauperate crinoid fauna, being instead dominated by trilobites, bryozoans, mollusks, and in some layers solenoporid algae? and stromatoporoids. One such setting is represented by the Grant Lake Formation, equivalent to the upper Corryville and Mount Auburn members of the McMillan Formation of Ohio, as exposed south of Flemingsburg, Fleming County, northern Kentucky. Described herein is an articulated crinoid crown (Anomalocrinus?) from this otherwise crinoid-poor interval. This occurrence may reflect either (1) a brief interval where conditions were more amenable to occupation by crinoids, possibly corresponding to a minor flooding surface, or (2) transportation of skeletal remains from nearby, deeper offshore areas that contained crinoids in greater abundance. The second interpretation seems more likely given the absence of in situ attachment structures and rarity of disarticulated column material at the study site. This study illustrates the value of echinoderm remains in paleoenvironmental analysis, the significance of crinoidal material in taphonomic interpretation of Paleozoic argillaceous carbonate deposits, and the sensitivity of crinoid fossils as indicators of allochthony or autochthony., INTRODUCTION Crinoids (Phylum Echinodermata) represent one of the most common and widespread faunal groups in the richly fossiliferous type Cincinnatian (Upper Ordovician: Katian) strata of the greater Cincinnati Arch region [...]

Author(s): Traci Watson Author Affiliations: Organisms named Fractofusus cover the sea floor some 560 million years ago, in a reconstruction of fossils from Newfoundland, Canada. Credit: Dr Charlotte G. Kenchington [...], Early fossils with guts, segmented bodies and other sophisticated features reveal a revolution in animal life -- before the Cambrian explosion. These bizarre species are rewriting animal evolution Early fossils with guts, segmented bodies and other sophisticated features reveal a revolution in animal life -- before the Cambrian explosion.

Western North America preserves iconic dinosaur faunas from the Upper Jurassic and Upper Cretaceous, but this record is interrupted by an approximately 20 Myr gap with essentially no terrestrial vertebrate fossil localities. This poorly sampled interval is nonetheless important because it is thought to include a possible mass extinction, the origin of orogenic controls on dinosaur spatial distribution, and the origin of important Upper Cretaceous dinosaur taxa. Therefore, dinosaurbearing rocks from this interval are of particular interest to vertebrate palaeontologists. In this study, we report on one such locality from Highwood Pass, Alberta. This locality has yielded a multitaxic assemblage, with the most diagnostic material identified so far including ankylosaurian osteoderms and a turtle plastron element. The fossil horizon lies within the upper part of the Pocaterra Creek Member of the Cadomin Formation (Blairmore Group). The fossils are assigned as Berriasian (earliest Cretaceous) in age, based on previous palynomorph analyses of the Pocaterra Creek Member and underlying and overlying strata. The fossils lie within numerous cross-bedded sandstone beds separated by pebble lenses. These sediments are indicative of a relatively high-energy depositional environment, and the distribution of these fossils over multiple beds indicates that they accumulated over multiple events, possibly flash floods. The fossils exhibit a range of surface weathering, having intact to heavily weathered cortices. The presence of definitive dinosaur material from near the Jurassic--Cretaceous boundary of Alberta establishes the oldest record of dinosaur body fossils in western Canada and provides a unique opportunity to study the Early Cretaceous dinosaur faunas of western North America. Key words: Ankylosauria, Berriasian, Blairmore Group, Cadomin Formation, Early Cretaceous, Kananaskis, osteoderm, Pocaterra Creek Member, Rocky Mountains, Testudines. Des assemblages de dinosaures emblematiques du Jurassique superieur au Cretace superieur sont preserves dans l'ouest de l'Amerique du Nord, mais ce registre est interrompu par une pause d'environ 20 millions d'annees caracterisee par l'absence presque totale de localites a fossiles de vertebres terrestres. Cet intervalle mal represente n'en est pas moins important parce qu'il comprendrait une possible extinction massive, l'origine de controles orogeniques de la repartition spatiale de dinosaures et l'origine d'importants taxons de dinosaures du Cretace superieur. Les roches renfermant des dinosaures de cet intervalle sont donc particulierement interessantes pour les paleontologues s'interessant aux vertebres. Nous faisons etat d'une telle localite a Highwood Pass (Alberta), qui a produit un assemblage multitaxons duquel le materiau le plus diagnostic obtenu a ce jour comprend des osteodermes ankylosauriens et un element de plastron de tortue. L'horizon fossilifere se trouve dans la partie superieure du membre de Pocaterra Creek de la Formation de Cadomin (Groupe de Blairmore). Un age berriasien (debut du Cretace) est attribue aux fossiles a la lumiere d'analyses anterieures de palynomorphes dans le membre de Pocaterra Creek et des strates sous-jacentes et sus-jacentes. Les fossiles sont presents dans de nombreux lits de gres a stratification croisee separes par des lentilles de galets. Ces sediments indiquent un milieu de depot assez dynamique, et la repartition des fossiles dans plusieurs lits indique qu'ils se sont accumules au fil de plusieurs evenements, possiblement des crues eclairs. Les fossiles presentent un eventail de types de meteorisation, montrant des cortex intacts a fortement meteorises. La presence de materiau definitivement dinosaurien a proximite de la limite Jurassique--Cretace de l'Alberta etablit la presence la plus ancienne de fossiles de corps de dinosaure dans l'Ouest canadien et offre une occasion unique d'etudier les assemblages de dinosaures du Cretace precoce de l'ouest de l'Amerique du Nord. [Traduit par la Redaction] Mots-cles : ankylosaures, Berriasien, Groupe de Blairmore, Formation de Cadomin, Cretace precoce, Kananaskis, osteoderme, membre de Pocaterra Creek, montagnes Rocheuses, testudines., Introduction The fossil record of dinosaurs is best sampled in North America, due to extensive deposits and ease of access. This is particularly the case in western North America, where [...]

Paleogene sediments of the Huntingdon Formation, a correlative to the Chuckanut Formation of neighbouring Washington State, USA, are exposed in the Greater Vancouver area, British Columbia, Canada. Palynology and plant macrofossils suggest the Kanaka Creek section is Paleocene rather than Eocene in age. Detrital zircon dating is less decisive, yet indicates the Kanaka rocks are no older than Maastrichtian. Analyses of plant macro- and micro-fossils suggest an early to middle Paleocene age for the Kanaka fossil flora. Paleocene indicators include macrofossils such as Platanus bella, Archeampelos, Hamamelites inequalis, and Ditaxocladus, and pollen taxa such as Paraalnipollenites, Triporopollenites mullensis, and Duplopollis. Paleogene taxa such as Woodwardia maxonii, Macclintockia, and Glyptostrobus dominate the flora. Fungal spores including the Late Cretaceous Pesavisparva and the Paleogene Pesavis tagluensis are notable age indicators. Physiognomy of 41 angiosperm leaf morphotypes from Kanaka Creek yields mean annual temperatures in the microthermal to lower mesothermal range (11.2 [+ or -] 4.3 to 14.6 [+ or -] 2.7 [degrees]C from leaf margin analysis; 14.8 [+ or -] 2.1 [degrees]C from Climate Leaf Analysis Multivariate Program), with mild winters (cold month mean temperature 3.9 [+ or -] 3.4 [degrees]C). Paleoclimate was cooler than the upper Paleocene and Eocene members of the Chuckanut Formation. Mean annual precipitation is estimated at ~140 cm with large uncertainties. The Kanaka paleoflora is reconstructed as a mixed conifer-broadleaf forest, sharing common taxa with other western North American Paleocene floras and growing in a temperate moist climate. Kanaka Creek is a rare coastal Paleocene plant locality that provides new insights into coastal vegetation and climate prior to the Paleocene-Eocene Thermal Maximum. Key words: Paleocene, paleobotany, palynology, paleoclimate, Huntingdon Formation, Kanaka Creek. Résumé : Des sédiments paléogènes de la Formation d'Huntingdon, une formation corrélative de la Formation de Chuckanut de l'État voisin de Washington (États-Unis), sont exposés dans la région de Vancouver (Colombie-Britannique, Canada). La palynologie et les macrofossiles de plantes donnent à penser que la coupe de Kanaka Creek est d'âge paléocène plutôt qu'éocène. Si la datation de zircons détritiques est moins concluante, elle indique toutefois que l'âge des roches de Kanaka n'est pas plus vieux que le Maastrichtien. Des analyses de macro- et microfossiles de plantes indiqueraient un âge paléocène précoce à moyen pour la flore fossile de Kanaka. Parmi les indicateurs paléocènes figurent des macrofossiles tels que Platanus bella, Archeampelos, Hamamelites inequalis et Ditaxocladus et des taxons de pollen tels que Paraalnipollenites, Triporopollenites mullensis et Duplopollis. Des taxons paléogènes comme Woodwardia maxonii, Macclintockia et Glyptostrobus sont dominants dans la flore. Des spores fongiques comprenant Pesavis parva d'âge crétacé tardif et Pesavis tagluensis d'âge paléogène sont des indicateurs d'âge notables. L'analyse physionomique de 41 morphotypes de feuilles d'angiosperme de Kanaka Creek produit des températures annuelles moyennes dans une fourchette allant de microthermique à mésothermique inférieure (de 11,2 [+ ou -] 4,3 [degré]C à 14,6 [+ ou -] 2,7 [degré]C obtenues de l'analyse de bordures de feuille, LMA; 14,8 [+ ou -] 2,1 [degré]C obtenue de CLAMP), avec des hivers doux (température moyenne des mois froids : 3,9 [+ or -] 3,4 [degré]C). Le paléoclimat était plus frais que ce qu'enregistrent les membres paléocène supérieur et éocène de la Formation de Chuckanut. Les précipitations annuelles moyennes sont estimées à ~140 cm, avec d'importantes incertitudes. La reconstitution de la paléoflore de Kanaka donne une forêt mixte à conifères-caducifoliés ayant des taxons en commun avec d'autres flores paléocènes de l'ouest de l'Amérique du Nord et croissant dans un climat tempéré humide. Kanaka Creek est une rare localité de plantes paléocènes côtières qui fournit de nouveaux renseignements sur la végétation et le climat côtiers avant le maximum thermique du passage Paléocène/Éocène. [Traduit par la Rédaction] Mots-clés : Paléocène, paléobotanique, palynologie, paléoclimat, Formation d'Huntingdon, Kanaka Creek., Introduction The main objectives of this paper are to assess the age assignment and paleoclimate of the Kanaka Creek paleoflora, southwestern British Columbia, Canada, using plant macrofossils as well as [...]

We report on pollen, plant macrofossils, and associated lithostratigraphy of a sediment core extracted from the base of Silver Lake, a kettle lake in northern Lower Michigan, USA, which reveal a complex deglacial scenario for ice block melting and lake formation, and subsequent plant colonization. Complementary multivariate statistical and squared chord distance analyses of the pollen data support these interpretations. The basal radiocarbon age from the core (17 540 cal years BP) is rejected as being anomalously old, based on biostratigraphic anomalies in the core and the date's incongruity with respect to the accepted regional deglaciation chronology. We reason that this erroneous age estimate resulted from the redeposition of middle-Wisconsin-age fossils by the ice sheet, mixed with the remains of plants that existed as the kettle lake formed at ca. 10 940 cal years BP by ice block ablation. Thereafter, the kettle lake became a reliable repository of Holocene-age fossils, documenting a mature boreal forest that existed until 10 640 cal years BP, followed by a pine-dominated mixed forest, an early variant of the mixed conifer-hardwood forest that persists to the present day. Our study demonstrates that researchers investigating kettle lakes, a common depositional archive for plant fossils in deglaciated landscapes, should exercise caution in interpreting the basal (Late Pleistocene/early Holocene-age) part of lake sediment cores. Key words: deglaciation, Holocene, kettle lakes, Michigan, pollen, radiocarbon dating. Nous rendons compte des pollens, des macrofossiles de plantes et de la lithostratigraphie associee d'une carotte de sediments extraite de la base du lac Silver, un lac de kettle situe dans le nord du bas Michigan (Etats-Unis), qui revelent un scenario de deglaciation complexe pour la fonte de blocs de glace et la formation de lacs, et la colonisation subsequente par des plantes. Des analyses statistiques multivariables et du carre de la distance de cordes complementaires des donnees sur le pollen appuient ces interpretations. L'age au carbone radioactif basal obtenu pour la carotte (17 540 a etal. BP) est rejete parce qu'il est anormalement vieux, a la lumiere d'anomalies biostratigraphiques dans la carotte et de l'incongruite de cet age par rapport a la chronologie de deglaciation regionale acceptee. Nous interpretons cet age estime errone comme etant le resultat du re-depot de fossiles d'age wisconsinien moyen par l'inlandsis, melanges aux restes de plantes qui existaient au moment de la formation du lac de kettle vers 10 940 a etal. BP par ablation de blocs de glace. Par la suite, le lac de kettle est devenu un centre de depot fiable de fossiles d'age holocene, qui documentent la foret boreale mature qui existait jusqu'a 10 640 a etal. BP, suivie d'une foret mixte dominee par les pins, une variante precoce de la foret mixte a coniferes et feuillus qui persiste a ce jour. L'etude demontre que les chercheurs qui etudient les lacs de kettle, une archive repandue de fossiles de plantes dans des paysages de deglaciation, devraient faire preuve de prudence dans l'interpretation de la partie basale (d'age pleistocene tardif a holocene precoce) de carottes de sediments de lac. [Traduit par la Redaction] Mots-cles : deglaciation, Holocene, lacs de kettle, Michigan, pollen, datation au carbone radioactif., Introduction Researchers are becoming increasingly aware of the challenges and intricacies of reconstructing terminal Pleistocene environments, including elucidating the timing of deglaciation events and the stages of landscape evolution at [...]