A5003696384- Plant and animal studies
- Ecology and Vegetation Dynamics Studies
- Plant Parasitism and Resistance
- Peatlands and Wetlands Ecology
- Insect and Arachnid Ecology and Behavior
- Coastal wetland ecosystem dynamics
- Botany, Ecology, and Taxonomy Studies
- Tropical and Extratropical Cyclones Research
- Climate Change Policy and Economics
- Botany and Plant Ecology Studies
- Wildlife Ecology and Conservation
- Animal Behavior and Reproduction
- Plant Reproductive Biology
- Insect and Pesticide Research
- Bryophyte Studies and Records
- Lichen and fungal ecology
- Plant Diversity and Evolution
- Climate variability and models
- Rangeland and Wildlife Management
- Soil Moisture and Remote Sensing
- Ecology and biodiversity studies
- Species Distribution and Climate Change
- Technology Assessment and Management
- Cryospheric studies and observations
- Animal Ecology and Behavior Studies
California State University, Northridge
2002-2022
Risk Management Solutions (United Kingdom)
2013-2019
McGill University
2016
Brown and Caldwell (United States)
2015
Met Office
2000
Washington University in St. Louis
1993
Stony Brook University
1992
State University of New York
1992
Iowa State University
1985
United States Fish and Wildlife Service
1985
▪ Abstract Floral evolution has often been associated with differences in pollination syndromes. Recently, this conceptual structure criticized on the grounds that flowers attract a broader spectrum of visitors than one might expect based their syndromes and diverge without excluding type pollinator favor another. Despite these criticisms, we show provide great utility understanding mechanisms floral diversification. Our conclusions are importance organizing pollinators into functional...
Costing out the effects of climate change Episodes severe weather in United States, such as present abundance rainfall California, are brandished tangible evidence future costs current trends. Hsiang et al. collected national data documenting responses six economic sectors to short-term fluctuations. These were integrated with probabilistic distributions from a set global models and used estimate during remainder this century across range scenarios (see Perspective by Pizer). In terms...
As exposure to coastal hazards increases there is growing interest in nature-based solutions for risk reduction. This study uses high-resolution flood and loss models quantify the impacts of wetlands northeastern USA on (i) regional damages by Hurricane Sandy (ii) local annual losses Barnegat Bay Ocean County, New Jersey. Using an extensive database property exposure, shows that avoided $625 Million direct during Sandy. The combines these with a synthetic storms County estimates 16% average...
Floral phenotypes may be as much the result of selection for avoidance some animal visitors improving interaction with better pollinators. When specializing on hummingbird-pollination, Penstemon flowers have evolved to improve morphological fit between bird and flower, or exclude less-efficient bees, both. We hypothesized how such might work four floral characters that affect mechanics pollen transfer: anther/stigma exsertion, presence a lower corolla lip, width tube, angle flower...
Abstract. Throughout the eastern United States, plant species distributions and community patterns have developed in response to heterogeneous environmental conditions a wide range of historical factors, including complex histories natural anthropogenic disturbance. Despite increased recognition importance disturbance determining forest composition structure, few studies assessed relative influence current environment factors on modern vegetation, part because detailed knowledge prior is...
For over a decade, Bateman's principle has been used to argue that the showy petals and sweet nectar of flowers are evolutionarily more male than female-that they adaptations principally for promoting export pollen rather setting seed. Here we present alternative views. (1) We question whether assumptions have generally upheld angiosperms. (2) path model contradicts by asserting floral attractiveness characters might well affect fitness deterministically through female function. (3) envision...
We compared pollen removal and deposition by hummingbirds bumblebees visiting bird‐syndrome Penstemon barbatus bee‐syndrome P. strictus flowers. One model for evolutionary shifts from bee pollination to bird has assumed that, mostly due grooming, on bodies quickly becomes unavailable transfer stigmas, whereas greater carryover. Comparing seeking nectar in strictus, we confirmed that bees had a steeper carryover curve than birds but, surprisingly, removed similar amounts of per‐visit...
Plants that experience variation in pollinator visitation rates or fluctuations weather conditions may be expected to have evolved homeostatic mechanisms regulate their nectar offerings, thereby providing a more constant reward the pollinators. A limited degree of such homeostasis is reported here for Penstemon . First, removal stimulates replenishment: when was removed hourly 6 h from P. speciosus , twice as much secreted cumulatively only at beginning and end same 6‐h period. Second,...
Male‐male competition in plants is thought to exert selection on flower morphology and the temporal presentation of pollen. Theory suggests that a plant's pollen dosing strategy should evolve match abundance transfer efficiency its pollinators. Simultaneous be favored when pollinators are infrequent or efficient at delivering they remove, whereas gradual optimize delivery by frequent wasteful Among Penstemon Keckiella species, anthers vary ways affect release, dried reliably indicates how...
Abstract Current models and theories of the formation maintenance microtopography in ombrotrophic peatlands (bogs) assume autogenic feedbacks between vegetation composition, water table depth (WTD) microtopography. A hypothesized outcome is a strong association among spatial variations WTD We tested corroborated this hypothesis using fine scale (<2 × 2 m ) data from two 20 plots at Mer Bleue, temperate bog. Furthermore, we partitioned variation plant communities into portions explained by...
Summary Wilson, P.: On inferring hybridity from morphological intermediacy. ‐ Taxon 41: 11–23. 1992. ISSN 0040‐0262. The type of intermediacy that separates divergence is not multivariate intermediacy; it the coincidence intermediate character states. For purpose showing hybridity, analyses should distinguish between two types (1) Hybrid indices fail to do so. (2) Principal components analysis does so only in an ambiguous way. (3) Pictorialized scatter diagrams properly present evidence for...
Few studies have surveyed the insects visiting flowers at many sites and for related species. Calochortus , a genus of about 60 species with its center diversity in California, has wide range appearances. Insects 25 were censused 40 sites. Visitors coflowering plants also each site. attracted several orders, especially beetles that feed glands on petals bees often collect pollen. Species section had somewhat narrower spectrum visitors than Mariposa . The visitor was greater On whole, seem to...
Abstract. Permafrost-affected ecosystems of the Arctic–boreal zone in northwestern North America are undergoing profound transformation due to rapid climate change. NASA's Arctic Boreal Vulnerability Experiment (ABoVE) is investigating characteristics that make these vulnerable or resilient this ABoVE employs airborne synthetic aperture radar (SAR) as a powerful tool characterize tundra, taiga, peatlands, and fens. Here, we present an annotated guide L-band P-band SAR data acquired during...
Earwigs (Insecta, Dermaptera) are characterized by uniquely elaborated cerci, commonly called forceps, the function of which remains unclear. We studied intrasexual and intersexual interactions in laboratory to examine context pattern forceps use toothed earwig. Vostox apictdenlatus (Caudell). Interactions between pairs earwigs were recorded four social situations: (1) two males, (2) males plus a virgin female, (3) females, (4) one male female. Forceps used as both weapons display structures...
WILSON, P. (Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303), M. BUONOPANE Bates College, Lewiston, ME 04240) AND T D. ALLISON Forestry and Wildlife, University Massachusetts, Amherst, MA 01002). Reproductive biology the monoecious clonal shrub Taxus canadensis. Bull. Torrey Bot. Club 123: 7-15 1996.-Strobilus production, pollination, maturation were studied in canadensis, a procumbent clonally-spreading shrub. Plants that produced many...
Flower size dimensions, colour, and nectar quantities potentially account for differences in pollinator species between Penstemon centranthifolius (Benth.) Benth. (tubular, red, nectar-rich, hummingbird pollinated) spectabilis Thurber (wide, purple, nectar-poor, hymenopteran pollinated). For this study, floral characters attraction were measured the two species, F 1 hybrids, backcrosses. Floral characters, color spectra combined hybrids a largely linear fashion, consistent with an...
The California Phenology Thematic Collections Network (CAP TCN) is a collaborative project that seeks to maximize the value of herbarium specimens and their data, especially for understanding changes in plant phenology due anthropogenic climate change. unites personnel herbaria at universities, research stations, natural history museums, botanic gardens with goal capturing images, transcribing label producing georeferenced coordinates nearly one million preserved collected over past 150+...
Abstract and Summary Group dynamics aggressive behavior of guanaco ( Lama guanicoe ) male groups (MGs) were described quantified. All‐male consisted yearling, subadult, adult males. Yearlings joined MGs from early Sep. to Feb., but the majority entered in Dec. Jan. Adult males dispersed Feb. establish or challenge tor territories. Young females occasionally observed MGs, not during height breeding season. Aggressive activity rates peaked Jan., older more aggressively active than younger...
Abstract We develop a stochastic North Atlantic hurricane track model whose climate inputs are main development region (MDR) and Indo-Pacific (IP) sea surface temperatures produce extremely long simulations for 58 different climates, each one conditioned on 5 yr of observed SSTs from 1950 to 2011—hereafter referred as medium-term (MT) views. Stringent tests then performed prove that MT better predictors landfalls than long-term view the entire SST time series 2011. In this analysis, authors...