105 Works

Effect of stressors on the carrying capacity of spatially distributed metapopulations

Bo Zhang, Donald DeAngelis, Wei-Ming Ni, Yuanshi Wang, Lu Zhai, Alex Kula, Shuang Xu & David Van Dyken
Stressors such as antibiotics, herbicides and pollutants are becoming increasingly common in the environment. The effects of stressors on populations are typically studied in homogeneous, non-spatial settings. However, most populations in nature are spatially distributed over environmentally heterogeneous landscapes with spatially-restricted dispersal. Little is known about the effects of stressors in these more realistic settings. Here, we combine laboratory experiments with novel mathematical theory to rigorously investigate how a stressor’s physiological effect and spatial distribution...

Understanding Behavioral Responses of Wildlife to Traffic to Improve Mitigation Planning

Fraser Shilling
Creating and maintaining sustainable transportation systems depends in part on understanding and mitigating ecological impacts. Wildlife crossing structures (WCS) are often used to mitigate impacts on wildlife populations. WCS and existing structures may provide passage for multiple species, depending on their sensitivity to traffic disturbance and perception of the roadway. In a previous project, we found that traffic conditions and traffic noise could reduce WCS effectiveness in facilitating passage of diverse and sensitive species. In...

Correlated evolution of sex allocation and mating system in wrasses and parrotfishes

Jennifer Hodge, Francesco Santini & Peter Wainwright
In accordance with predictions of the size-advantage model, comparative evidence confirms that protogynous sex change is lost when mating behavior is characterized by weak size advantage. However, we lack comparative evidence supporting the adaptive significance of sex change. Specifically, it remains unclear whether increasing male size advantage induces transitions to protogynous sex change across species, as it can within species. We show that in wrasses and parrotfishes (Labridae), the evolution of protogynous sex change is...

Channel types predictions for the Sacramento River basin

Hervé Guillon, Colin F. Byrne, Belize Arela Albin Lane, Samuel Sandoval Solis & Gregory Brian Pasternack
Hydrologic and geomorphic classifications have gained traction in response to the increasing need for basin-wide water resources management. Regardless of the selected classification scheme, an open scientific challenge is how to extend information from limited field sites to classify tens of thousands to millions of channel reaches across a basin. To address this spatial scaling challenge, we leveraged machine learning to predict reach-scale geomorphic channel types using publicly available geospatial data.

Root and shoot variation in relation to potential intermittent drought adaptation of Mesoamerican wild common bean (Phaseolus vulgaris L.)

Paul Gepts, Jorge Carlos Berny Mier Y Teran, Enéas R Konzen, Viviana Medina, Antonia Palkovic, Andrea Ariani, Siu M. Tsai & Matthew E. Gilbert
• Background Wild crop relatives have been potentially subjected to stresses on an evolutionary time scale prior to domestication. Among these stresses, drought is one of the main factors limiting crop productivity and its impact is likely to increase under current scenarios of global climate change. We sought to determine to what extent wild common bean (Phaseolus vulgaris) exhibited adaptation to drought stress, whether this potential adaptation is dependent on the climatic conditions of the...

Data from: Fostering the use of zero and near zero emission vehicles in freight operations

Miguel Jaller, Leticia Pineda, Yasar Gueldas, Farzad Alemi & Irem Otay
California has put forward a number of goals to improve freight efficiency through the introduction and use of zero and near-zero emission vehicles. However, the technical and operational characteristics, market readiness, and other factors related to these technologies can be very different. Therefore, the most appropriate option for different uses (e.g., last mile, long-haul distribution) and users’ preferences is not necessarily clear. This study focused on analyzing the factors to foster the adoption of zero...

Integrated Crop-Livestock Systems achieve comparable crop yields to specialized systems: a meta-analysis

Caitlin Peterson, Leonardo Deiss & Amelie Gaudin
Production systems that feature temporal and spatial integration of crop and livestock enterprises, also known as integrated crop-livestock systems (ICLS), have the potential to intensify production on cultivated lands and foster resilience to the effects of climate change without proportional increases in environmental impacts. Yet, crop production outcomes following livestock grazing across environments and management scenarios remain uncertain and a potential barrier to adoption, as producers worry about the effects of livestock activity on the...

Data from: Forests do not limit bumble bee foraging movements in a montane meadow complex

John Mola, Michael Miller, Sean O'Rourke & Neal Williams
Understanding the roles of habitat fragmentation and resource availability in shaping animal movement are integral for promoting species persistence and conservation. For insects like bumble bees, their movement patterns affect the survival and reproductive potential of their colonies as well as the pollen flow of plant species. However, our understanding of their mobility or the impact of putative barriers in natural environments is limited due to the technical difficulties of studying wild populations. We used...

Data from: Measuring behavior patterns and evaluating time sampling methodology to characterize brush use in weaned beef cattle

Kelsey Horvath, Rachel Toaff-Rosenstein, Cassandra Tucker & Emily Miller-Cushon
With growing interest in provision of brushes to cattle, and implications of brush use for behavioral development and welfare, there is a need to validate methodology for quantifying grooming behavior. Our objectives were to characterize patterns of brush use, including bouts, diurnal activity, and individual variability over 24-h periods and to validate time sampling methodologies to characterize these traits, including instantaneous recording at various time intervals and continuous recording for subsets of the day. Data...

Data from: Comparisons of Late Ordovician ecosystem dynamics before and after the Richmondian Invasion reveal consequences of invasive species in benthic marine paleocommunities

Hannah Kempf, Ian Castro, Ashley Dineen, Carrie Tyler & Peter Roopnarine
A thorough understanding of how communities respond to extreme changes, such as biotic invasions, is essential to manage ecosystems today. Here we constructed fossil food webs to identify changes in Late Ordovician (Katian) shallow marine paleocommunity structure and functioning before and after the Richmondian Invasion, a well-documented ancient invasion. Food webs were compared using descriptive metrics and Cascading Extinction on Graphs models. Richness at intermediate trophic levels was underrepresented when using only data from the...

Data from: Frequency-dependent fitness and reproductive dynamics contribute to habitat segregation in sympatric Jewelflowers

Kyle Christie & Sharon Y. Strauss
Coexistence results from a complex suite of past and contemporary processes including biogeographic history, adaptation, ecological interactions, and reproductive dynamics. Here we explore drivers of local micro-parapatry in which two closely related and reproductively isolated Streptanthus species (Jewelflower, Brassicaceae) inhabit continuous or adjacent habitat patches and occur within seed dispersal range, yet rarely overlap in fine-scale distribution. We find some evidence for abiotic niche partitioning and local adaptation, however differential survival across habitats cannot fully...

Data from: Feeding and damage-induced volatile cues make beetles disperse and produce a more even distribution of damage for sagebrush

Richard Karban & Louie Yang
1. Induced plant responses to herbivory are common and we have learned a lot about the mechanisms of induced resistance and their effects on herbivore performance. We know less about their effects on herbivore behavior and especially on spatial patterns of damage. 2. Theoretical models predict that induced responses can cause patterns of damage to become aggregated, random, or even. A recent model predicted that informed herbivore movement coupled with communication between plants would make...

Data from: Attacks on genetic privacy via uploads to genealogical databases

Doc Edge & Graham Coop
Direct-to-consumer (DTC) genetics services are increasingly popular for genetic genealogy, with tens of millions of customers as of 2019. Several DTC genealogy services allow users to upload their own genetic datasets in order to search for genetic relatives. The statement that a user's uploaded genome shares one or more segments in common with that of a target person in the database---that is, that the two genomes share one or more regions identical by state (IBS)---reveals...

Data from: Evolved phenological cueing strategies show variable responses to climate change

Collin B. Edwards & Louie H. Yang
Several studies have documented a global pattern of phenological advancement that is consistent with ongoing climate change. However, the magnitude of these phenological shifts is highly variable across taxa and locations. This variability of phenological responses has been difficult to explain mechanistically. To examine how the evolution of multi-trait cueing strategies could produce variable responses to climate change, we constructed a model in which organisms evolve strategies that integrate multiple environmental cues to inform anticipatory...

Data from: Efficacy of masks and face coverings in controlling aerosol particle emission from expiratory activities

Sima Asadi, William Ristenpart, Santiago Barreda, Anthony Wexler, Nicole Bouvier & Christopher Cappa
The dataset provided here is associated with the work "Efficacy of masks and face coverings in controlling aerosol particle emission from expiratory activities," by Asadi et al. This includes measurements made of the influence of different types of face coverings (surgical masks, both vented and unvented N95 respirators, and homemade fabric and paper towel masks) on the emission of micron-scale aerosols from various expiratory activities (coughing, breathing, speaking).

Data from: Local government contribution to recovery of the giant gartersnake (Thamnophis gigas)

Steven Greco
Recovery of a threatened or endangered species usually requires conservation and mitigation actions at the local level across the species' entire range (i.e., geographic limits of a species' spatial distribution). Depending on the size of the range it could involve numerous or few jurisdictions. Under the federal Endangered Species Act an optional off-set program allows local governments to create a Habitat Conservation Plan (HCP) to guide mitigative actions (streamlining permitting) and in the state of...

Bayesian total-evidence inference resolves the position of the ant genus Phaulomyrma (Hymenoptera, Formicidae)

Zachary Griebenow
Although molecular data have proven indispensable in confidently resolving the phylogeny of many clades across the tree of life, these data may be inaccessible for certain taxa. The resolution of taxonomy in the ant subfamily Leptanillinae is made problematic by the absence of DNA sequence data for leptanilline taxa that are known only from male specimens, including the monotypic genus Phaulomyrma Wheeler & Wheeler. Focusing upon the considerable diversity of undescribed male leptanilline morphospecies, the...

Supporting data for: The setup and relaxation of spring upwelling in a deep, rotationally influenced lake

Derek Roberts & S. Geoffrey Schlaodow
Supporting data for the manuscript "The setup and relaxation of spring upwelling in a deep, rotationally influenced lake" accepted for publication in Limnology and Oceanography in November 2020. The data herein were collected at Lake Tahoe, CA/NV, USA in May-June, 2018 as part of a collaboration between the UC Davis Tahoe Environmental Research Center, the UC Davis Bodega Marine Lab, and the Stanford Environmental Fluid Mechanics Laboratory. The goal of this data collection effort was...

Factors affecting woodrat abundance over 70 years

Wolfgang Abad, Jose Morales-Doo, Carly Pomeroy & Adrienne Ung
Woodrats are ecosystem engineers that can increase biodiversity by physically changing the environment. In doing so, they alter landscapes and increase the number of microhabitats for other organisms. In order to better understand woodrats’ role in their ecosystem, we surveyed big-eared woodrat (Neotoma macrotis) houses in Hastings Natural History Reservation located in Monterey County, California. For each house, we determined its usability and measured its size. We found a 26 percent increase in population density...

Effects of volatile compounds in California bay trees (Umbellularia californica) on vegetation growth and insect herbivory

Ashley Adornato, Hannah Gerber, Sarah Haas & Jennifer Perez
Secondary metabolites are volatile compounds produced by plants that can be used as defense mechanisms for reducing stressors such as herbivory and competition. Leaves, roots, and stems of California bay trees (Umbellularia californica) get their notable aroma from secondary metabolites called monoterpenes, which are allelopathic constituents in many other plants, such as eucalyptus. In this study, we investigated the potential allelopathic and anti-herbivory effects of California bay trees by examining their understory composition, germination rates...

Bird community interactions at water sources at Hastings Natural History Reservation

Christina Cen, Killian Fay, Joselyne Jaramillo & Jason Ku
In seasonally dry areas, artificial water sources become a gathering place for a variety of avian species, leading to interactions between birds whose niches otherwise do not overlap. To maximize water use while reducing negative costs associated with conflict and predation, birds adopt anti-predation behaviors and engage in differing levels of tolerant and conflict interactions. In order to better understand how birds interact and behave at artificial water resources, we examined whether species and flock...

Acorn woodpeckers (Melanerpes formicivorus) exhibit more predator avoidance behavior post-fire

Emily Drake, , Youssef Hanna & Johnson Ku
Climate change has increased the frequency of wildfires globally. This increase in wildfires causes many animals to adjust their behaviors in order to cope with the more regular disturbances occurring in their habitats. It is often thought that birds are less affected by disturbances such as fire because of their ability to easily relocate by flying, but species with high levels of territoriality, such as acorn woodpeckers (Melanerpes formicivorus), may be more greatly affected by...

Channel types predictions for the South Fork Eel River basin

Hervé Guillon, Colin F. Byrne, Belize A. Lane, Samuel Sandoval Solis & Gregory B. Pasternack
Hydrologic and geomorphic classifications have gained traction in response to the increasing need for basin-wide water resources management. Regardless of the selected classification scheme, an open scientific challenge is how to extend information from limited field sites to classify tens of thousands to millions of channel reaches across a basin. To address this spatial scaling challenge, we leveraged machine learning to predict reach-scale geomorphic channel types using publicly available geospatial data.

Evolution of the Greater Caucasus basement and formation of the Main Caucasus Thrust, Georgia

Dylan Vasey, Eric Cowgill, Sarah Roeske, Nathan Niemi, Tea Godoladze, Irakli Skhirtladze & Salome Gogoladze
Along the northern margin of the Arabia-Eurasia collision zone in the western Greater Caucasus, the Main Caucasus Thrust (MCT) juxtaposes Paleozoic crystalline basement to the north against Mesozoic metasedimentary and volcaniclastic rocks to the south. The MCT is commonly assumed to be the trace of an active plate-boundary scale structure that accommodates Arabia-Eurasia convergence, but field data supporting this interpretation are equivocal. Here we investigate the deformation history of the rocks juxtaposed across the MCT...

Analytical Modeling Framework to Assess the Economic and Environmental Impacts of Residential Deliveries, and Evaluate Sustainable City Logistics Strategies

Anmol Pahwa & Miguel Jaller
In the last decade, e‐commerce has grown substantially, increasing business‐to‐business, business‐to‐consumer, and consumer‐to‐consumer transactions. As a result, there has been a continuous growth in last mile operations, especially deliveries to residential areas, bringing along externalities such as congestion, air and noise pollution, and energy consumption. This project aims to develop an analytical framework to model last mile operations based on continuous approximation techniques. The model will help estimate the economic and environmental impacts of residential...

Registration Year

  • 2020

Resource Types

  • Dataset
  • Text
  • Software


  • University of California, Davis
  • University of California, Berkeley
  • United States Geological Survey
  • University of Minnesota
  • United States Department of Agriculture
  • University of Florida
  • University of California, Santa Cruz
  • Cornell University
  • SUNY Downstate Medical Center
  • California State University, Northridge