A5082357235- Evolution and Paleontology Studies
- Wildlife Ecology and Conservation
- Pleistocene-Era Hominins and Archaeology
- Species Distribution and Climate Change
- Marine animal studies overview
- Isotope Analysis in Ecology
- Geology and Paleoclimatology Research
- Arctic and Antarctic ice dynamics
- Bat Biology and Ecology Studies
- Ecology and Vegetation Dynamics Studies
- Cephalopods and Marine Biology
- Food Industry and Aquatic Biology
- Amphibian and Reptile Biology
- Transportation Planning and Optimization
- Underwater Acoustics Research
- Indigenous Studies and Ecology
- Transportation and Mobility Innovations
- Archaeology and ancient environmental studies
- Marine and environmental studies
- Urban Transport and Accessibility
- Urban Agriculture and Sustainability
- Tree-ring climate responses
- Chromosomal and Genetic Variations
- Geological formations and processes
- Ichthyology and Marine Biology
Carleton University
2014-2025
Canadian Museum of Nature
2015-2025
National Museum of Natural History
2016-2025
Smithsonian Institution
2016-2024
University of Wyoming
2021
McMaster University
2021
Toronto Metropolitan University
2021
University of Calgary
2009-2014
Microwear, the quantification of microscopic scratches and pits on occlusal surfaces tooth enamel, is a commonly used as paleodietary proxy. For ungulates (hoofed mammals), scratch-dominant microwear distinguishes modern grazers from browsers, presumably result abrasion grass phytoliths (biogenic silica). However, it also likely that exogenous grit (i.e., soil, dust) contributing factor to these patterns, which may reflect soil ingestion varies with feeding height and/or environmental...
Large mammals are at high risk of extinction globally. To understand the consequences their demise for community assembly, we tracked structure through end-Pleistocene megafaunal in North America. We decomposed effects biotic and abiotic factors by analyzing co-occurrence within mutual ranges species pairs. Although shifting climate drove an increase niche overlap, decreased, signaling shifts interactions. Furthermore, effect on remained constant over time while decreased. Biotic apparently...
Understanding extinction drivers in a human-dominated world is necessary to preserve biodiversity. We provide an overview of Quaternary extinctions and compare mammalian events on continents islands after human arrival system-specific prehistoric historic contexts. highlight the role body size life-history traits these extinctions. find significant size-bias except for small times. Using phylogenetic regression classification trees, we that while are poor predictors extinctions, those...
Sexual selection is one of the earliest areas interest in evolutionary biology. And yet, history sexually dimorphic traits remains poorly characterized for most vertebrate lineages. Here, we report on evidence early evolution dimorphism within a model mammal group, pinnipeds. Pinnipeds show range sexual and mating systems that span extremes modern mammals, from monomorphic taxa with isolated dispersed to extreme size highly ordered polygynous harem systems. In addition, degree pinnipeds...
Toothed whales (Odontoceti) are adapted for catching prey underwater and possess some of the most derived feeding specializations all mammals, including loss milk teeth (monophyodonty), high tooth count (polydonty), discrete classes (homodonty). Many extant odontocetes combination short, broad rostra, reduced counts, fleshy lips, enlarged hyoid bones-all adaptations suction upon fishes squid. We report a new fossil odontocete from Oligocene (approx. 30 Ma) South Carolina (Inermorostrum...
Abstract A variety of tooth‐wear and morphological dietary proxies have been proposed for ungulates. In turn, they applied to fossil specimens with the purpose reconstructing diets extinct taxa. Although these used in isolation combination, a consistent set statistical analyses has never all available datasets. The this study is determine how well most commonly classify ungulates as browsers, grazers, mixed feeders individually combination. Discriminant function analysis individual...
Abstract Biotic homogenization—increasing similarity of species composition among ecological communities—has been linked to anthropogenic processes operating over the last century. Fossil evidence, however, suggests that humans have had impacts on ecosystems for millennia. We quantify biotic homogenization North American mammalian assemblages during late Pleistocene through Holocene (~30,000 ybp recent), a timespan encompassing increased evidence landscape (~20,000–14,000 ybp). From ~10,000...
In the past decade, ancient protein sequences have emerged as a valuable source of data for deep-time phylogenetic inference. Still, recovery providing novel insights does not exceed 3.7 Ma (Pliocene). Here, we push this boundary back to 21-24 (early Miocene), by retrieving enamel an early-diverging rhinocerotid ( Epiaceratherium sp. - CMNF-59632) from Canadian High Arctic. We recover partial seven proteins (AHSG, ALB, AMBN, AMELX, AMTN, ENAM, MMP20) and over 1000 peptide-spectrum matches,...
Climate affects habitat, food availability, and the movement sustainability of all life. In this work, we apply Indigenous Western scientific methods, including genomics isotope profiling, on fossils from across Beringia to explore effect climate change horses. We find that Late Pleistocene horses Alaska northern Yukon are related populations Eurasia crossed Bering land bridge multiple times during last glacial interval. also deeply divergent lineages north south American ice sheets...
The recent advent of low magnification microwear analysis has allowed the efficient study entire vertebrate faunas using only an optical stereomicroscope. Photographic visualization by this means proven difficult, however, and, as a result, few high-resolution photos have been published. repeatability method also questioned because involves visual inspection features. We show that use high dynamic range imaging improves features in photographs and these counting medium increases method. from...
Spatial diversity patterns are thought to be driven by climate-mediated processes. However, temporal of community composition remain poorly studied. We provide two complementary analyses North American mammal diversity, using (i) a paleontological dataset (2077 localities with 2493 taxon occurrences) spanning 21 discrete subdivisions the Cenozoic based on Land Mammal Ages (36 Ma – present), and (ii) climate space model predictions for 744 extant mammals under eight scenarios future change....
Abstract In the absence of independent observational data, ecologists and paleoecologists use proxies for Eltonian niches species (i.e., resource or dietary axes niche). Some exploit fact that mammalian teeth experience wear during mastication, due to both tooth‐on‐tooth food‐on‐tooth interactions. The distribution types detectible at micro‐ macroscales are highly correlated with preferences individuals and, in turn, species. Because methods quantify tooth analytical methods) do so by direct...
Abstract Extension of the mesowear method to include lower cheek teeth ruminants will dramatically increase sample sizes and thus statistical power paleodietary inferences. However, F ortelius S olounias, which was designed for application upper molars, does not effectively separate ruminant species by diet when applied teeth. Upper scores have sometimes been compared among non‐analogous cusps (i.e. buccal maxillary teeth, experience incursion mandibular excursion during chewing stroke). We...
Animal richness, community composition, and phylogenetic structure (PCS) vary across the modern landscape. communities from phylogenetically clustered (i.e. higher relatedness amongst co-occurring species than is expected by chance) to even taxa are more distantly related chance), which explained abiotic or climatic filtering competitive exclusion, respectively. Under this model, contribution of historical origination extinction events animal PCS remains relatively unknown. Because determine...
ABSTRACT Several studies have quantified selective capability in artiodactyls using skeletal correlates such as the premaxillary shape index (PSI), incisor arcade breadth (IAB), curvature (DOC), and width ratio (IWR). These metrics are limited their applicability because they do not account for potential importance of muzzle length. Herein we apply a new method quantification (the dentary [DSI]) that combines length width. We find browsers possess longest, narrowest muzzles, whereas muzzles...
Studies of paleoenvironments have commonly focused on large mammalian herbivores such as ungulates. Many localities, however, yielded numbers small herbivores, including lagomorphs and rodents. These fossils represent an untapped paleoecological resource. However, the are often in form isolated teeth, microwear analysis cannot be used due to taphonomic alteration. As a result, we use ungulate gross dental wear model. The features extant western Canadian identified create dietary categories...
Premise of research. Change in base number chromosomes per nucleus is usually believed to result from whole-genome duplication or elimination a single chromosome (aneuploidy). However, numbers can also change via mechanisms with no gain loss nuclear DNA, such as fusion fission chromosomes.Methodology. We previously determined amount DNA (2C values) using flow cytometry leaf tissue. tested whether Cycadales (cycad) are correlated these 2C values ordinary least squares (OLS) and phylogenetic...
Abstract Studying the deep-time origins of macroecological phenomena can help us to understand their long-term drivers. Given considerable spatiotemporal bias terrestrial fossil record, it behooves how much biological information is lost. The aim this study establish whether latitudinal diversity gradients are detectable in a biased record. I develop simulated fossilization approach, weighting probability mammal species appearing record based on body size and geographic-range size; larger...
AbstractHuman-mediated species invasion and climate change are leading to global extinctions predicted result in the loss of important axes phylogenetic functional diversity. However, long-term robustness modern communities is unknown, given limited timescales over which they can be studied. Using fossil record Paleocene-Eocene thermal maximum (PETM; ∼56 Ma) North America, we evaluate mammalian community-level response a rapid warming event (5°-8°C) by three Eurasian orders undergoing...
Abstract Aim Many hypotheses posit that species‐rich tropical communities are dominated by species–species interactions, apparent as competitive exclusion or character displacement, whereas species‐poor temperate species–environment interactions. Recent studies demonstrate a strong influence of macroevolutionary and biogeographical factors. We simultaneously test for the effects species climate biotic interchange on Western Hemisphere mammal using phylogenetic functional diversity approach....
ABSTRACT The evolution of robust jaws, hypsodont teeth, and large chewing muscles among grazing ruminants is a quintessential example putative morphological adaptation. However, the degree correlated (i.e., to what extent grazer feeding apparatus represents an evolutionary module), especially soft hard tissues, remains poorly understood. Recent generation datasets phylogenetic information has made testing hypotheses possible. We, therefore, test for various traits ruminant masticatory...
The late Quaternary of North America was marked by prominent ecological changes, including the end‐Pleistocene megafaunal extinction, spread human settlements and rise agriculture. Here we examine mechanistic reasons for temporal changes in mammal species association body size during this time period. Building upon co‐occurrence results from Lyons et al. (2016) – wherein each pair classified as spatially aggregated, segregated or random examined mass differences (BMD) between type period...
Extinction events in the geological past are similar to present-day biodiversity crisis that they have a pronounced biogeography, producing dramatic changes spatial distributions of species. Reconstructing palaeobiogeographic patterns from fossils therefore allows us examine long-term processes governing formation regional biotas, and potentially helps build spatially explicit models for future loss. However, extent which biogeographic can be preserved fossil record is not well understood....