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Fruits, Frugivores, And The Evolution Of Phytochemical Diversity, Susan R. Whitehead, Gerald F. Schneider, Ray Dybzinski, Annika S. Nelson, Mariana Gelambi, Elsa Jos, Noelle G. Beckman Jun 2021

Fruits, Frugivores, And The Evolution Of Phytochemical Diversity, Susan R. Whitehead, Gerald F. Schneider, Ray Dybzinski, Annika S. Nelson, Mariana Gelambi, Elsa Jos, Noelle G. Beckman

Biology Faculty Publications

Plants produce an enormous diversity of secondary metabolites, but the evolutionary mechanisms that maintain this diversity are still unclear. The interaction diversity hypothesis suggests that complex chemical phenotypes are maintained because different metabolites benefit plants in different pairwise interactions with a diversity of other organisms. In this synthesis, we extend the interaction diversity hypothesis to consider that fruits, as potential hotspots of interactions with both antagonists and mutualists, are likely important incubators of phytochemical diversity. We provide a case study focused on the Neotropical shrub Piper reticulatum that demonstrates: 1) secondary metabolites in fruits have complex and cascading effects for …


Investigating The Direct And Indirect Effects Of Forest Fragmentation On Plant Functional Diversity, Jenny Zambrano, Norbert J. Cordeiro, Carol Garzon-Lopez, Lauren Yeager, Claire Fortunel, Henry J. Ndangalasi, Noelle G. Beckman Jul 2020

Investigating The Direct And Indirect Effects Of Forest Fragmentation On Plant Functional Diversity, Jenny Zambrano, Norbert J. Cordeiro, Carol Garzon-Lopez, Lauren Yeager, Claire Fortunel, Henry J. Ndangalasi, Noelle G. Beckman

Biology Faculty Publications

Ongoing habitat loss and fragmentation alter the functional diversity of forests. Generalising the magnitude of change in functional diversity of fragmented landscapes and its drivers is challenging because of the multiple scales at which landscape fragmentation takes place. Here we propose a multi-scale approach to determine whether fragmentation processes at the local and landscape scales are reducing functional diversity of trees in the East Usambara Mountains, Tanzania. We employ a structural equation modelling approach using five key plant traits (seed length, dispersal mode, shade tolerance, maximum tree height, and wood density) to better understand the functional responses of trees to …


What Does The Snake Eat? Breadth, Overlap, And Non-Native Prey In The Diet Of Three Sympatric Natricine Snakes, Emily E. Virgin, Richard B. King Apr 2019

What Does The Snake Eat? Breadth, Overlap, And Non-Native Prey In The Diet Of Three Sympatric Natricine Snakes, Emily E. Virgin, Richard B. King

Biology Faculty Publications

We investigated diet breadth and diet overlap in three sympatric snakes of similar body size: Dekay’s Brownsnakes (Storeria dekayi), Red-bellied Snakes (S. occipitomaculata), and sub-adult Common Gartersnakes (Thamnophis sirtalis), by examining recently consumed prey (n = 388) collected from wild-caught snakes (n = 263) in northern Illinois. Storeria occipitomaculata were dietary specialists, feeding nearly exclusively on slugs. Storeria dekayi fed predominately on slugs but also consumed snails and earthworms. Sub-adult T. sirtalis fed predominately on earthworms but also consumed frogs and small mammals. Diet overlap was extensive between Storeria species but relatively low between …


On The Relationship Between Phylogenetic Diversity And Trait Diversity, Caroline M. Tucker, T. Jonathan Davies, Marc W. Cadotte, William D. Pearse May 2018

On The Relationship Between Phylogenetic Diversity And Trait Diversity, Caroline M. Tucker, T. Jonathan Davies, Marc W. Cadotte, William D. Pearse

Biology Faculty Publications

Niche differences are key to understanding the distribution and structure of biodiversity. To examine niche differences, we must first characterize how species occupy niche space, and two approaches are commonly used in the ecological literature. The first uses species traits to estimate multivariate trait space (so‐called functional trait diversity, FD); the second quantifies the amount of time or evolutionary history captured by a group of species (phylogenetic diversity, PD). It is often—but controversially—assumed that these putative measures of niche space are at a minimum correlated and perhaps redundant, since more evolutionary time allows for greater accumulation of trait changes. This …


Monitoring Of Dung Beetle (Scarabaeidae And Geotrupidae) Activity Along Maryland's Coastal Plain, Patrick Simons, Michael Molina, Mallory A. Hagadorn, Dana L. Price Mar 2018

Monitoring Of Dung Beetle (Scarabaeidae And Geotrupidae) Activity Along Maryland's Coastal Plain, Patrick Simons, Michael Molina, Mallory A. Hagadorn, Dana L. Price

Biology Faculty Publications

Our understanding of how human activities impact insect communities is limited. Dung beetles, well known for the ecosystem services they provide, are faced with many conservation threats, particularly from deforestation and agriculture. Here we used 200-m transects and human-dung—baited pitfall traps to examine dung beetle populations in 7 forests of Maryland's Coastal Plain. We set traps once a month, from May 2014 to April 2015, to determine species presence, abundance, range, and seasonality. We collected 6463 individuals representing 22 species; Janes Island State Park (JISP) had the highest abundance (2705 individuals) and Martinak State Park (MSP) had the highest species …


Hosts, Nesting Behavior, And Ecology Of Some North American Spider Wasps (Hymenoptera: Pompilidae), Ii, Frank E. Kurczewski, Glavis B. Edwards, James P. Pitts Jan 2017

Hosts, Nesting Behavior, And Ecology Of Some North American Spider Wasps (Hymenoptera: Pompilidae), Ii, Frank E. Kurczewski, Glavis B. Edwards, James P. Pitts

Biology Faculty Publications

This monograph is a continuation of a multiyear study of the genera and species of North American spider wasps (Pompilidae) and their spider host families, genera and species, nesting behavior, ecology, and natural communities. The study enlarges and enhances host preference, nesting behavior, and ecological information for 77 North American pompilid taxa. The first North American Pompilidae records for the families Tengellidae and Segestriidae, both from central coastal California, are reported herein. New host spider genera and species are listed for many of the pompilid species, including the first North American host record for Dipogon (Dipogon) g. graenicheri …


The Distribution Of Fruit And Seed Toxicity During Development For Eleven Neotropical Trees And Vines, Noelle G. Beckman Jul 2013

The Distribution Of Fruit And Seed Toxicity During Development For Eleven Neotropical Trees And Vines, Noelle G. Beckman

Biology Faculty Publications

Secondary compounds in fruit mediate interactions with natural enemies and seed dispersers, influencing plant survival and species distributions. The functions of secondary metabolites in plant defenses have been well-studied in green tissues, but not in reproductive structures of plants. In this study, the distribution of toxicity within plants was quantified and its influence on seed survival was determined in Central Panama. To investigate patterns of allocation to chemical defenses and shifts in allocation with fruit development, I quantified variation in toxicity between immature and mature fruit and between the seed and pericarp for eleven species. Toxicity of seed and pericarp …


Widespread Triploidy In Western North American Aspen (Populus Tremuloides), Karen E. Mock, Colin M. Callahan, M. Nurul Islam-Faridi, John D. Shaw, Hardeep S. Rai, Stewart C. Sanderson, Carol A. Rowe, Ronald J. Rye, Michael D. Madritch, Richard S. Gardner, Paul G. Wolf Jan 2012

Widespread Triploidy In Western North American Aspen (Populus Tremuloides), Karen E. Mock, Colin M. Callahan, M. Nurul Islam-Faridi, John D. Shaw, Hardeep S. Rai, Stewart C. Sanderson, Carol A. Rowe, Ronald J. Rye, Michael D. Madritch, Richard S. Gardner, Paul G. Wolf

Biology Faculty Publications

We document high rates of triploidy in aspen (Populus tremuloides) across the western USA (up to 69% of genets), and ask whether the incidence of triploidy across the species range corresponds with latitude, glacial history (as has been documented in other species), climate, or regional variance in clone size. Using a combination of microsatellite genotyping, flow cytometry, and cytology, we demonstrate that triploidy is highest in unglaciated, drought-prone regions of North America, where the largest clone sizes have been reported for this species. While we cannot completely rule out a low incidence of undetected aneuploidy, tetraploidy or duplicated loci, our …


Loss Of Foundation Species Increases Population Growth Of Exotic Forbs In Sagebrush Steppe, J S. Prevey, M J. Germino, Nancy J. Huntly Jan 2010

Loss Of Foundation Species Increases Population Growth Of Exotic Forbs In Sagebrush Steppe, J S. Prevey, M J. Germino, Nancy J. Huntly

Biology Faculty Publications

The invasion and spread of exotic plants following land disturbance threatens semiarid ecosystems. In sagebrush steppe, soil water is scarce and is partitioned between deeprooted perennial shrubs and shallower-rooted native forbs and grasses. Disturbances commonly remove shrubs, leaving grass-dominated communities, and may allow for the exploitation of water resources by the many species of invasive, tap-rooted forbs that are increasingly successful in this habitat. We hypothesized that exotic forb populations would benefit from increased soil water made available by removal of sagebrush, a foundation species capable of deep-rooting, in semiarid shrub-steppe ecosystems. To test this hypothesis, we used periodic matrix …


The Taxonomic Designation Of Eriogonum Corymbosum Var. Nilesii (Polygonaceae) Is Supported By Aflp And Cpdna Analyses, M. W. Ellis, J. M. Roper, R. Gainer, J. P. Der, Paul G. Wolf Jan 2009

The Taxonomic Designation Of Eriogonum Corymbosum Var. Nilesii (Polygonaceae) Is Supported By Aflp And Cpdna Analyses, M. W. Ellis, J. M. Roper, R. Gainer, J. P. Der, Paul G. Wolf

Biology Faculty Publications

We examined populations of perennial, shrubby buckwheats in the Eriogonum corymbosum complex and related Eriogonum species in the subgenus Eucycla, to assess genetic affiliations of the recently named E. corymbosum var. nilesii. The known populations of this varietyare all located in Clark County, Nevada, U. S. A. We compared AFLP profiles and chloroplast DNA sequences of plants sampled from populations of E. corymbosum var. nilesii with those of plants representing other E. corymbosum varieties and related Eriogonum species from Colorado,Utah, northern Arizona, and northern New Mexico. We found evidence of genetic cohesion among the Clark County populations as well astheir …


On Estimating The Exponent Of Power-Law Frequency Distributions, Ethan P. White, B. J. Enquist, J. L. Green Jan 2008

On Estimating The Exponent Of Power-Law Frequency Distributions, Ethan P. White, B. J. Enquist, J. L. Green

Biology Faculty Publications

Power-law frequency distributions characterize a wide array of natural phenomena. In ecology, biology, and many physical and social sciences, the exponents of these power-laws are estimated to draw inference about the processes underlying the phenomenon, to test theoretical models, and to scale up from local observations to global patterns. Therefore, it is essential that these exponents be estimated accurately. Unfortunately, the binning-based methods traditionally utilized in ecology and other disciplines perform quite poorly. Here we discuss more sophisticated methods for fitting these exponents based on cumulative distribution functions and maximum likelihood estimation. We illustrate their superior performance at estimating known …


Effects Of Recording Media On Echolocation Data From Broadband Bat Detectors, Ethan P. White, S. D. Gehrt Jan 2001

Effects Of Recording Media On Echolocation Data From Broadband Bat Detectors, Ethan P. White, S. D. Gehrt

Biology Faculty Publications

Bat detectors are an important tool for ecological studies of bats. However, the quality and quantity of data may be affected by the recording devices used to record the output from the detector. We compared recordings of bat activity from audiocassette recorders and computers. Numbers of calls/hour, passes/hour, identifiable passes/hour, and feeding buzzes/hour were similar (all P’s > 0.1) between recording devices. All call characteristics, except for the minimum frequency and characteristic frequency, differed (P < 0.05) between tapes and computers. Species identification with discriminate function analysis was less reliable with tape data than with computer data, particularly when the model built with computer-recorded reference calls was tested with tape-recorded calls. Therefore, we suggest when tape recorders are used for field recording that they also are used to record reference calls.


A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker Jan 2001

A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker

Biology Faculty Publications

No abstract provided.