A5019999102- Geology and Paleoclimatology Research
- Plant Diversity and Evolution
- Evolution and Paleontology Studies
- Ecology and Vegetation Dynamics Studies
- Paleontology and Stratigraphy of Fossils
- Geological Studies and Exploration
- Botany, Ecology, and Taxonomy Studies
- Plant and animal studies
- Plant and Fungal Species Descriptions
- Geological formations and processes
- Hydrocarbon exploration and reservoir analysis
- Methane Hydrates and Related Phenomena
- Isotope Analysis in Ecology
- Paleontology and Evolutionary Biology
- Pasture and Agricultural Systems
- Botany and Plant Ecology Studies
- Geological and Geophysical Studies
- Climate variability and models
- Plant Water Relations and Carbon Dynamics
- Fern and Epiphyte Biology
- Climate change and permafrost
- Pleistocene-Era Hominins and Archaeology
- Microbial Metabolism and Applications
- Bat Biology and Ecology Studies
- Ecology and biodiversity studies
Brandon University
2016-2025
Plant & Food Research
2023
University of Auckland
2023
University of Southampton
2022
The University of Tokyo
2022
Royal Tyrrell Museum
2022
Centre National pour la Recherche Scientifique et Technique (CNRST)
2022
University of South Australia
2014
University of Saskatchewan
1992-2011
Royal Botanic Garden Sydney
2007
Research Article| November 01, 1995 Eocene continental climates and latitudinal temperature gradients David R. Greenwood; Greenwood 1Department of Paleobiology, National Museum Natural History, MRC 121, Smithsonian Institution, Washington, D.C. 20560 Search for other works by this author on: GSW Google Scholar Scott L. Wing Author Article Information Publisher: Geological Society America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print 0091-7613 Geology (1995) 23 (11): 1044–1048....
The geological record encodes the relationship between climate and atmospheric carbon dioxide (CO 2 ) over long short timescales, as well potential drivers of evolutionary transitions. However, reconstructing CO beyond direct measurements requires use paleoproxies herein lies challenge, proxies differ in their assumptions, degree understanding, even reconstructed values. In this study, we critically evaluated, categorized, integrated available to create a high-fidelity transparently...
Research Article| March 01, 1998 Using fossil leaves as paleoprecipitation indicators: An Eocene example Peter Wilf; Wilf 1Department of Paleobiology, MRC 121, National Museum Natural History, Smithsonian Institution, Washington, D.C. 20560 Search for other works by this author on: GSW Google Scholar Scott L. Wing; Wing David R. Greenwood; Greenwood 2Department Biological and Food Sciences, Victoria University Technology, St. Albans Campus, P.O. Box 14428, MCMC, Melbourne, 8001, Australia...
There are many methods for inferring terrestrial palaeoclimates from palaeontological data, including the size and species diversity of ectothermic vertebrates, locomotor dental adaptations mammals, characteristics leaf shape, size, epidermis, wood anatomy, climatic preferences nearest living relatives fossil taxa. Estimates palaeotem perature have also been based on stable oxygen isotope ratios in shells bones. Interpretation any these data relies some way uniformitarian assumptions,...
The late Early to early Middle Eocene Okanagan Highlands fossil sites, spanning ~1000 km northsouth (northeastern Washington State, southern British Columbia) provide an opportunity reconstruct biotic communities across a broad upland landscape during the warmest part of Cenozoic. Plant taxa from these sites are characteristic modern eastern North American deciduous forest zone, principally mixed mesophytic forest, but also include extinct taxa, known only Asian mesothermal forests, and...
Temperatures in the Arctic have increased by an astounding 1 °C response to anthropogenic forcing over past 20 years and are expected rise further coming decades. The Pliocene (2.6–5.3 Ma) is of particular interest as analog for future warming because global temperatures were significantly warmer than today a sustained period time, with continental configurations similar present. Here, we estimate mean annual temperature (MAT) based upon three independent proxies from early peat deposit...
Early–middle Eocene (ca. 53–38 Ma) sediments of the Eureka Sound Group in Canada’s Arctic Archipelago preserve evidence lush mixed conifer-broadleaf rain forests, inhabited at times by alligators, turtles, and diverse mammals, including primates, tapirs, brontotheres, hippo-like Coryphodon. This biota reflects a greenhouse world, offering climatic ecologic deep time analog mild ice-free that may be our best means to predict what is store for future if current climate change goes unchecked....
In the modern world, biotic diversity is typically higher in low-latitude tropical regions where there abundant insolation (light and heat) low thermal seasonality. Because these factors broadly covary with latitude, separating their possible effects on species difficult. The Eocene was a much more equable however, temperature seasonality extending into lower-insolation higher, cooler latitudes, allowing us to test by comparing insect (1) modern, temperate, low-insolation, highly seasonal...
Early Eocene global climate was warmer than much of the Cenozoic and punctuated by a series transient warming events or 'hyperthermals' associated with carbon isotope excursions when temperature increased 4–8 °C. The Paleocene-Eocene Thermal Maximum (PETM, ~55 Ma) 2 (ETM2, 53.5 hyperthermals were short duration (<200 kyr) dramatically restructured terrestrial vegetation mammalian faunas at mid-latitudes. Data on character magnitude change in during after PETM ETM2 high northern latitudes,...
Fossil palms provide qualitative evidence of (sub-) tropical conditions and frost-free winters in the geological past, including modern cold climate regions (e.g., boreal, or polar climates). The freeze intolerance varies across different organs life stages, with seedlings particular less tolerant sub-zero temperatures than adult plants, limiting successful establishment populations while permitting to survive cultivation outside their natural ranges. Quantitatively, indicate minimum month...
Abstract Earth's hydrological cycle is expected to intensify in response global warming, with a “wet‐gets‐wetter, dry‐gets‐drier” anticipated over the ocean. Subtropical regions (∼15°–30°N/S) are predicted become drier, yet proxy evidence from past warm climates suggests these may be characterized by wetter conditions. Here we use an integrated data‐modeling approach reconstruct and zonal‐mean rainfall patterns during early Eocene (∼56–48 million years ago). The Deep‐Time Model...
Research Article| January 01, 2010 How wet was the Arctic Eocene rain forest? Estimates of precipitation from Paleogene macrofloras David R. Greenwood; Greenwood 1Department Biology, Brandon University, 270 18th Street, Brandon, Manitoba R7A 6A9, Canada Search for other works by this author on: GSW Google Scholar James F. Basinger; Basinger 2Department Geological Sciences, University Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Robin Y. Smith Geology (2010) 38 (1):...
Abstract. The Paleocene–Eocene Thermal Maximum (PETM) represents a ~170 kyr episode of anomalous global warmth ~56 Ma ago. PETM is associated with rapid and massive injections 13C-depleted carbon into the ocean–atmosphere system reflected as prominent negative isotope excursion (CIE) in sedimentary components. Earth's surface deep ocean waters warmed by ~5 °C, which part may have occurred prior to CIE. However, few records document continental climatic trends changes seasonality not been...
Abstract Current knowledge of terrestrial ecosystem response to the Paleocene-Eocene Thermal Maximum (PETM; ca. 56 Ma) is largely based on midlatitudes Northern Hemisphere. To more fully reconstruct global PETM, we generated vegetation and biomarker proxy records from an outcrop section southern coast Australia (∼60°S paleolatitude). We documented a rapid, massive, sustained turnover as regional PETM warming ∼1–4 °C, abruptly transitioning warm temperate meso-megathermal rain forest similar...
Other| April 01, 2004 Paleotemperature Estimation Using Leaf-Margin Analysis: Is Australia Different? DAVID R. GREENWOOD; GREENWOOD 1Sustainability Group, Victoria University, St Albans Campus, PO Box 14428, Melbourne City MC, VIC 8001, Australia, David.Greenwood@vu.edu.au Search for other works by this author on: GSW Google Scholar PETER WILF; WILF 2Department of Geosciences, Pennsylvania State University Park, PA 16802 SCOTT L. WING; WING 3Department Paleobiology, National Museum Natural...
Palynofloras from the middle Early to early Middle Eocene Okanagan Highlands (northern Washington State and southern British Columbia) are used reconstruct vegetation across a broad upland landscape. In this preliminary report, forest floristic composition is reconstructed using palynological analysis of sediments Republic, Washington; localities Allenby Formation in Princeton region (Hospital Hill, One Mile Creek Summers Road), Hat Creek, McAbee, Falkland, Horsefly, Driftwood Canyon,...
Research Article| February 01, 2008 Onset of long-term cooling Greenland near the Eocene-Oligocene boundary as revealed by branched tetraether lipids Stefan Schouten; Schouten 1Royal Netherlands Institute for Sea Research, Department Marine Biogeochemistry and Toxicology, P.O. Box 59, 1790 AB, Den Burg, Texel, Search other works this author on: GSW Google Scholar James Eldrett; Eldrett 2Shell UK Exploration Production, 1 Altens Farm Road, Nigg, Aberdeen AB12 3FY, David R. Greenwood;...
Early Eocene land bridges allowed numerous plant and animal species to cross between Europe North America via the Arctic. While many suited prevailing cool Arctic climates would have been able throughout much of this period, others found dispersal opportunities only during limited intervals when their requirements for higher temperatures were met. Here, we present Titanomyrma lubei gen. et sp. nov. from Wyoming, USA, a new giant (greater than 5 cm long) formiciine ant early (approx. 49.5 Ma)...
Significance Elevated CO 2 combined with globally warm temperatures in the Eocene make its climate ideal for understanding modern global warming and biotic consequences. Globally low temperature seasonality—the relationship between winter mean annual temperatures—has been proposed as key to differential biodiversity community patterns. Palms are important indicators by their sensitivity frost; however, presence paleocommunities may be masked taphonomic constraints identification...