USGS Science⌕ Search

SEARCH · USGS Science

Results for “Ecology and Evolution”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 775 records · Page 43Linked to original sources

Plant size, latitude, and phylogeny explain within-population variability in herbivory

Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.

Science↗

Eradication efforts catalyze rapid evolution in an invasive predatory fish

pecies invasions spur costly and labor-intensive control efforts, yet even local eradication is seldom achieved. When control measures are initially effective, they may drive evolutionary adaptation that prevents full eradication, as has been documented for some chemical and biocontrol approaches. Although the intensity, directionality, and persistence of selection required to increase the frequency of resistant genotypes in complex natural ecosystems remains an open question, theory predicts that high mortality can cause life-history evolution even in the absence of a strong selective agent. Here, we use annually collected ecological and genetic data to show that rapid evolution of introduced smallmouth bass has undermined a 20-y manual suppression effort in a mid-sized lake. Despite nearly doubling annual mortality, our intensive control program produced a larger bass population dominated by young and early-maturing fish. These shifts were accompanied by large allele frequency changes in three genomic regions associated with earlier maturation and increased somatic growth. Our findings bear out the theoretical prediction that high mortality can drive evolutionary adaptation in target species. Controlling species invasions are worldwide practices that typically remove a substantial proportion of a population during each of many successive generations, hence life history adaptation may be commonplace. Such evolutionary responses could be salient in explaining the widespread failure of invasion control efforts. Genetic and phenotypic monitoring to detect cryptic adaptation and preemptive design of invader eradication programs to deliberately disrupt directional selection for resistance could improve invasion control outcomes.

New York↗

Ecoregions of the conterminous United States: Evolution of a hierarchical spatial framework

A map of ecological regions of the conterminous United States, first published in 1987, has been greatly refined and expanded into a hierarchical spatial framework in response to user needs, particularly by state resource management agencies. In collaboration with scientists and resource managers from numerous agencies and institutions in the United States, Mexico, and Canada, the framework has been expanded to cover North America, and the original ecoregions (now termed Level III) have been refined, subdivided, and aggregated to identify coarser as well as more detailed spatial units. The most generalized units (Level I) define 10 ecoregions in the conterminous U.S., while the finest-scale units (Level IV) identify 967 ecoregions. In this paper, we explain the logic underpinning the approach, discuss the evolution of the regional mapping process, and provide examples of how the ecoregions were distinguished at each hierarchical level. The variety of applications of the ecoregion framework illustrates its utility in resource assessment and management.

Environmental Management↗

Metamorphosis in an era of increasing climate variability

Most animals have complex life cycles including metamorphosis or other discrete life stage transitions during which individuals may be particularly vulnerable to environmental stressors. With climate change, individuals will be exposed to increasing thermal and hydrologic variability during metamorphosis, which may affect survival and performance through physiological, behavioral, and ecological mechanisms. Furthermore, because metamorphosis entails changes in traits and vital rates, it is likely to play an important role in how populations respond to increasing climate variability. To identify mechanisms underlying population responses and associated trait and life history evolution, we need new approaches to estimating changes in individual traits and performance throughout metamorphosis, and we need to integrate metamorphosis as an explicit life stage in analytical models.

Trends in Ecology & Evolution↗

Representing plant diversity in land models: An evolutionary approach to make ‘Functional Types’ more functional

Plants are critical mediators of terrestrial mass and energy fluxes, and their structural and functional traits have profound impacts on local and global climate, biogeochemistry, biodiversity, and hydrology. Yet Earth System Models (ESMs), our most powerful tools for predicting the effects of humans on the coupled biosphere-atmosphere system, simplify the incredible diversity of land plants into a handful of coarse categories of ‘Plant Functional Types’ (PFTs) that often fail to capture ecological dynamics such as biome distributions. The inclusion of more realistic functional diversity is a recognized goal for ESMs, yet there is currently no consistent, widely accepted way to add diversity to models, i.e. to determine what new PFTs to add and with what data to constrain their parameters. We review approaches to representing plant diversity in ESMs and draw on recent ecological and evolutionary findings to present an evolution-based functional type approach for further disaggregating functional diversity. Specifically, the prevalence of niche conservatism, or the tendency of closely related taxa to retain similar ecological and functional attributes through evolutionary time, reveals that evolutionary relatedness is a powerful framework for summarizing functional similarities and differences among plant types. We advocate that Plant Functional Types based on dominant evolutionary lineages (‘Lineage Functional Types’) will provide an ecologically defensible, tractable, and scalable framework for representing plant diversity in next-generation ESMs, with the potential to improve parameterization, process representation, and model benchmarking. We highlight how the importance of evolutionary history for plant function can unify the work of disparate fields to improve predictive modeling of the Earth system.

Global Change Biology↗

Landscape changes elevate the risk of avian influenza virus diversification and emergence in the East Asian–Australasian Flyway

Highly pathogenic avian influenza viruses (HPAIV) persistently threaten wild waterfowl, domestic poultry, and public health. The East Asian–Australasian Flyway plays a crucial role in HPAIV dynamics due to its large populations of migratory waterfowl and poultry. Over recent decades, this flyway has undergone substantial landscape changes, including both losses and gains of waterfowl habitats. These changes can affect waterfowl distributions, increase contact with poultry, and consequently alter ecological conditions that favor avian influenza virus (AIV) evolution. However, limited research has assessed these likely impacts. Here, we integrated empirical data and an individual-based model to simulate AIV transmission in migratory waterfowl and domestic poultry, including wild-to-poultry spillover and reassortment dynamics in poultry, across landscapes representing the years 2000 and 2015. We used the reassortment incidence as a proxy for ecological and transmission conditions that support viral diversification and the emergence of novel subtypes. Our simulations show that landscape change reshaped the waterfowl distribution, facilitated bird aggregation at improved habitats, increased coinfection, and raised reassortment rate by 1,593%, indicating a substantially higher potential for viral diversification and emergence. Model-generated risk maps show expanded and increased reassortment risk in southeastern China, the Yellow River Basin, and northeastern China. These findings suggest the importance of landscape change as a driver of potential AIV diversification and subtype emergence. This underscores the need for interdisciplinary approaches that integrate landscape dynamics, host movement, and viral evolution to better assess and mitigate future risk.

East Asian–Australasian Flyway↗

Cold-seep habitat mapping: high-resolution spatial characterization of the Blake Ridge Diapir seep field

Relationships among seep community biomass, diversity, and physiographic controls such as underlying geology are not well understood. Previous efforts to constrain these relationships at the Blake Ridge Diapir were limited to observations from piloted deep-submergence vehicles. In August 2012, the autonomous underwater vehicle (AUV) Sentry collected geophysical and photographic data over a 0.131 km2 area at the Blake Ridge Diapir seeps. A nested survey approach was used that began with a regional or reconnaissance-style survey using sub-bottom mapping systems to locate and identify seeps and underlying conduits. This survey was followed by AUV-mounted sidescan sonar and multibeam echosounder systems mapping on a mesoscale to characterize the seabed physiography. At the most detailed survey level, digital photographic imaging was used to resolve sub-meter characteristics of the biology. Four pockmarks (25–70 m diameter) were documented, each supporting chemosynthetic communities. Concentric zonation of mussels and clams suggests the influence of chemical gradients on megafaunal distribution. Data collection and analytical techniques used here yield high-resolution habitat maps that can serve as baselines to constrain temporal evolution of seafloor seeps, and to inform ecological niche modeling and resource management.

Deep-Sea Research Part II: Topical Studies in Ocea↗

Gully annealing by aeolian sediment: field and remote-sensing investigation of aeolian-hillslope-fluvial interactions, Colorado River corridor, Arizona, USA

Processes contributing to development of ephemeral gully channels are of great importance to landscapes worldwide, and particularly in dryland regions where soil loss and land degradation from gully erosion pose long-term land-management problems. Whereas gully formation has been relatively well studied, much less is known of the processes that anneal gullies and impede their growth. This study of gully annealing by aeolian sediment, spanning 95 km along the Colorado River corridor in Glen, Marble, and Grand Canyon, Arizona, USA, employed field and remote sensing observations, including digital topographic modelling. Results indicate that aeolian sediment activity can be locally effective at counteracting gully erosion. Gullies are less prevalent in areas where surficial sediment undergoes active aeolian transport, and have a greater tendency to terminate in active aeolian sand. Although not common, examples exist in the record of historical imagery of gullies that underwent infilling by aeolian sediment in past decades and evidently were effectively annealed. We thus provide new evidence for a potentially important interaction of aeolian–hillslope–fluvial processes, which could affect dryland regions substantially in ways not widely recognized. Moreover, because the biologic soil crust plays an important role in determining aeolian sand activity, and so in turn the extent of gully development, this study highlights a critical role of geomorphic–ecologic interactions in determining arid-landscape evolution.

Arizona↗

Report of the USGS Coastal and Marine Geology Modeling Workshop, Pacific Marine Science Center, Santa Cruz, CA, March 22-23, 2005

A U.S. Geological Survey (USGS) Coastal and Marine Geology (CMG) Modeling Workshop was held to discuss the general topic of coastal modeling, defined broadly to include circulation, waves, sediment transport, water quality, ecology, sediment diagenesis, morphology change, and coastal evolution, on scales ranging from seconds and a few centimeters (individual ripples) to centuries (coastal evolution) and thousands of kilometers (tsunami propagation). The workshop was convened at the suggestion of CMG Program Management to improve communication among modelers and model users, assess modeling-related activities being conducted at the three centers (Florida Integrated Science Center, FISC; Pacific Marine Science Center; PMSC; and Woods Hole Science Center; WHSC), and develop goals, strategies, and plans for future modeling activities. The workshop represents a step toward developing a five-year strategic plan, and was timed to provide input for the FY06 prospectus. The workshop was held at the USGS Pacific Marine Science Center in Santa Cruz on March 22-23, 2005.

Open-File Report↗

A new Liopropoma sea bass (Serranidae, Epinephelinae, Liopropomini) from deep reefs off Curaçao, southern Caribbean, with comments on depth distributions of western Atlantic liopropomins

Collecting reef-fish specimens using a manned submersible diving to 300 m off Curaçao, southern Caribbean, is resulting in the discovery of numerous new fish species. The new Liopropoma sea bass described here differs from other western Atlantic members of the genus in having VIII, 13 dorsal-fin rays; a moderately indented dorsal-fin margin; a yellow-orange stripe along the entire upper lip; a series of approximately 13 white, chevron-shaped markings on the ventral portion of the trunk; and a reddish-black blotch on the tip of the lower caudal-fin lobe. The new species, with predominantly yellow body and fins, closely resembles the other two “golden basses” found together with it at Curaçao: L. aberrans and L. olneyi . It also shares morphological features with the other western Atlantic liopropomin genus, Bathyanthias . Preliminary phylogenetic data suggest that western Atlantic liopropomins, including Bathyanthias , are monophyletic with respect to Indo-Pacific Liopropoma , and that Bathyanthias is nested within Liopropoma , indicating a need for further study of the generic limits of Liopropoma . The phylogenetic data also suggest that western Atlantic liopropomins comprise three monophyletic clades that have overlapping depth distributions but different depth maxima (3–135 m, 30–150 m, 133–411 m). The new species has the deepest depth range (182–241 m) of any known western Atlantic Liopropoma species. Both allopatric and depth-mediated ecological speciation may have contributed to the evolution of western Atlantic Liopropomini.

Caribbean Sea↗

Editorial: Combining the science and practice of restoration ecology-Case studies of a grassroots binational restoration collaborative in the Madrean Archipelago Ecoregion (2014- 2019)

The Sky Island Restoration Collaborative (SIRC) is a growing partnership between government agencies, nonprofit organizations, and private landowners in southeast Arizona, the United States, and northern Sonora, Mexico. Starting in 2014 as an experiment to cultivate restoration efforts by connecting people across vocations and nations, SIRC has evolved over 5 years into a flourishing landscape-restoration initiative. The group is founded on the concept of developing a restoration economy, where ecological and socioeconomic benefits are interconnected and complimentary. The variety of ideas, people, field sites, administration, and organizations promote learning and increase project success through iterative adaptive management, transparency, and sharing. The collaborative seeks to make restoration self-sustaining and improve quality of life for citizens living along the US-Mexico border. Research and experiments are developed between scientists and practitioners to test hypotheses, qualify procedures, and quantify impacts on shared projects. Simultaneously, partners encourage and facilitate connecting more people to the landscape—via volunteerism, internships, training, and mentoring. Through this history, SIRC’s evolution is pioneering the integration of community and ecological restoration to protect biodiversity in the Madrean Archipelago Ecoregion. This editorial introduces SIRC as a unique opportunity for scientists and practitioners looking to engage in binational partnerships and segues into this special journal issue we have assembled that relates new findings in the field of restoration ecology.

Arizona, New Mexico↗

The relationship between parental age and reproductive effort in the California Gull (Larus californicus)

Reproductive effort was compared among California gulls ranging in age from 3 to 18 years old. Results indicated that reproductive effort increased with parental age. Older parents (11–18 years old) invested more in foraging effort and in defense of offspring than did younger parents (<10 years old), and did so over a greater period of time. Increases with age in the efficiency of parenting could not be demonstrated. Increased levels of reproductive effort, therefore, appeared to be the main factor responsible for age-related increases in breeding success. The higher levels of reproductive effort of old parents were associated with higher mortality. Thus, data support the prediction that a cost-benefit system of risk of mortality vs reproductive gain operates in this population. Higher levels of reproductive effort can increase an individual's reproductive success; however, it also increases the likelihood that it will die. Therefore, for the young parent, high risks of mortality involved in current production would be too costly (in terms of loss of future reproductive success) to justify the benefit of high current reproductive output. Parents achieve the highest likelihood of maximizing life-time reproductive output by increasing reproductive effort with age as the cost of mortality diminishes. Data testing the relationship between parental age and reproductive effort demonstrate the existence of age-related variation in reproductive investment. They also demonstrate that the concept of reproductive value proposed by Fisher (1930) has validity as a framework which supports much of our theory on life history evolution.

Behavioral Ecology and Sociobiology↗

Rangeland health attributes and indicators for qualitative assessment

Panels of experts from the Society for Range Management and the National Research Council proposed that status of rangeland ecosystems could be ascertained by evaluating an ecological site's potential to conserve soil resources and by a series of indicators for ecosystem processes and site stability. Using these recommendations as a starting point, we developed a rapid, qualitative method for assessing a moment-in-time status of rangelands. Evaluators rate 17 indicators to assess 3 ecosystem attributes (soil and site stability, hydrologic function, and biotic integrity) for a given location. Indicators include rills, water flow patterns, pedestals and terracettes, bare ground, gullies, wind scour and depositional areas, litter movement, soil resistance to erosion, soil surface loss or degradation, plant composition relative to infiltration, soil compaction, plant functional/structural groups, plant mortality, litter amount, annual production, invasive plants, and reproductive capability. In this paper, we detail the development and evolution of the technique and introduce a modified ecological reference worksheet that documents the expected presence and amount of each indicator on the ecological site. In addition, we review the intended applications for this technique and clarify the differences between assessment and monitoring that lead us to recommend this technique be used for moment-in-time assessments and not be used for temporal monitoring of rangeland status. Lastly, we propose a mechanism for adapting and modifying this technique to reflect improvements in understanding of ecosystem processes. We support the need for quantitative measures for monitoring rangeland health and propose some measures that we believe may address some of the 17 indicators.

Journal of Range Management↗

Novel ecological and climatic conditions drive rapid adaptation in invasive Florida Burmese pythons

Invasive species provide powerful in situ experimental systems for studying evolution in response to selective pressures in novel habitats. While research has shown that phenotypic evolution can occur rapidly in nature, few examples exist of genome‐wide adaptation on short ‘ecological’ timescales. Burmese pythons ( Python molurus bivittatus ) have become a successful and impactful invasive species in Florida over the last 30 years despite major freeze events that caused high python mortality. We sampled Florida Burmese pythons before and after a major freeze event in 2010 and found evidence for directional selection in genomic regions enriched for genes associated with thermosensation, behavior, and physiology. Several of these genes are linked to regenerative organ growth, an adaptive response that modulates organ size and function with feeding and fasting in pythons. Independent histological and functional genomic datasets provide additional layers of support for a contemporary shift in invasive Burmese python physiology. In the Florida population, a shift towards maintaining an active digestive system may be driven by the fitness benefits of maintaining higher metabolic rates and body temperature during freeze events. Our results suggest that a synergistic interaction between ecological and climatic selection pressures have driven adaptation in Florida Burmese pythons, demonstrating the often‐overlooked potential of rapid adaptation to influence the success of invasive species.

Florida↗

Genomic characterization of highly pathogenic H5 avian influenza viruses from Alaska during 2022 provides evidence for genotype-specific trends of spatiotemporal and interspecies dissemination

The ongoing panzootic of highly pathogenic H5 clade 2.3.4.4b avian influenza (HPAI) spread to North America in late 2021, with detections of HPAI viruses in Alaska beginning in April 2022. HPAI viruses have since spread across the state, affecting many species of wild birds as well as domestic poultry and wild mammals. To better understand the dissemination of HPAI viruses spatiotemporally and among hosts in Alaska and adjacent regions, we compared the genomes of 177 confirmed HPAI viruses detected in Alaska during April – December 2022. Results suggest multiple viral introductions into Alaska between November 2021 and August or September 2022, as well as dissemination to areas within and outside of the state. Viral genotypes differed in their spatiotemporal spread, likely influenced by timing of introductions relative to population immunity. We found evidence for dissemination of HPAI viruses between wild bird species, wild birds and domestic poultry, as well as wild birds and wild mammals. Continued monitoring for and genomic characterization of HPAI viruses in Alaska can improve our understanding of the evolution and dispersal of these economically costly and ecologically relevant pathogens.

Emerging Microbes & Infections↗

Niche evolution and adaptive radiation: Testing the order of trait divergence

In the course of an adaptive radiation, the evolution of niche parameters is of particular interest for understanding modes of speciation and the consequences for coexistence of related species within communities. We pose a general question: In the course of an evolutionary radiation, do traits related to within-community niche differences (?? niche) evolve before or after differentiation of macrohabitat affinity or climatic tolerances (?? niche)? Here we introduce a new test to address this question, based on a modification of the method of independent contrasts. The divergence order test (DOT) is based on the average age of the nodes on a tree, weighted by the absolute magnitude of the contrast at each node for a particular trait. The comparison of these weighted averages reveals whether large divergences for one trait have occurred earlier or later in the course of diversification, relative to a second trait; significance is determined by bootstrapping from maximum-likelihood ancestral state reconstructions. The method is applied to the evolution of Ceanothus, a woody plant group in California, in which co-occurring species exhibit significant differences in a key leaf trait (specific leaf area) associated with contrasting physiological and life history strategies. Co-occurring species differ more for this trait than expected under a null model of community assembly. This ?? niche difference evolved early in the divergence of two major subclades within Ceanothus, whereas climatic distributions (?? niche traits) diversified later within each of the subclades. However, rapid evolution of climate parameters makes inferences of early divergence events highly uncertain, and differentiation of the ?? niche might have taken place throughout the evolution of the group, without leaving a clear phylogenetic signal. Similar patterns observed in several plant and animal groups suggest that early divergence of ?? niche traits might be a common feature of niche evolution in many adaptive radiations. ?? 2006 by the Ecological Society of America.

Ecology↗

New uses for ancient middens: Bridging ecological and evolutionary perspectives

Rodent middens provide a fine-scale spatiotemporal record of plant and animal communities over the late Quaternary. In the Americas, middens have offered insight into biotic responses to past environmental changes and historical factors influencing the distribution and diversity of species. However, few studies have used middens to investigate genetic or ecosystem level responses. Integrating midden studies with neoecology and experimental evolution can help address these gaps and test mechanisms underlying eco-evolutionary patterns across biological and spatiotemporal scales. Fully realizing the potential of middens to answer cross-cutting ecological and evolutionary questions and inform conservation goals in the Anthropocene will require a collaborative research community to exploit existing midden archives and mount new campaigns to leverage midden records globally.

Trends in Ecology and Evolution↗