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Full-Text Articles in Biology

A Global Agenda For Advancing Freshwater Biodiversity Research, Alain Maasri, Sonja C. Jähnig, Hendrik Freitag, 93 Co-Authors Dec 2021

A Global Agenda For Advancing Freshwater Biodiversity Research, Alain Maasri, Sonja C. Jähnig, Hendrik Freitag, 93 Co-Authors

Biology Faculty Publications

Global freshwater biodiversity is declining dramatically, and meeting the challenges of this crisis requires bold goals and the mobilisation of substantial resources. While the reasons are varied, investments in both research and conservation of freshwater biodiversity lag far behind those in the terrestrial and marine realms. Inspired by a global consultation, we identify 15 pressing priority needs, grouped into five research areas, in an effort to support informed stewardship of freshwater biodiversity. The proposed agenda aims to advance freshwater biodiversity research globally as a critical step in improving coordinated actions towards its sustainable management and conservation.


In Memoriam: Ignacio Ribera (1963–2020), Emmanuel D. Delocado, Michael Balke, Hendrik Freitag Jan 2020

In Memoriam: Ignacio Ribera (1963–2020), Emmanuel D. Delocado, Michael Balke, Hendrik Freitag

Biology Faculty Publications

No abstract provided.


A Comparison Of Drone Imagery And Groundbased Methods For Estimating The Extent Of Habitat Destruction By Lesser Snow Geese (Anser Caerulescens Caerulescens) In La Pérouse Bay, Andrew F. Barnas, Brian J. Darby, Gregory S. Vandeberg, Robert F. Rockwell, Susan N. Ellis-Felege Aug 2019

A Comparison Of Drone Imagery And Groundbased Methods For Estimating The Extent Of Habitat Destruction By Lesser Snow Geese (Anser Caerulescens Caerulescens) In La Pérouse Bay, Andrew F. Barnas, Brian J. Darby, Gregory S. Vandeberg, Robert F. Rockwell, Susan N. Ellis-Felege

Biology Faculty Publications

Lesser snow goose (Anser caerulescens caerulescens) populations have dramatically altered vegetation communities through increased foraging pressure. In remote regions, regular habitat assessments are logistically challenging and time consuming. Drones are increasingly being used by ecologists to conduct habitat assessments, but reliance on georeferenced data as ground truth may not always be feasible. We estimated goose habitat degradation using photointerpretation of drone imagery and compared estimates to those made with ground-based linear transects. In July 2016, we surveyed five study plots in La Pérouse Bay, Manitoba, to evaluate the effectiveness of a fixed-wing drone with simple Red Green Blue …


Presence And Distribution Of Leptodactylus Guianensis Heyer And De Sa, 2011 In Colombia: Comparisons With Other Species In The L. Latrans Group., Mariela Osorno Muñoz, Doris L. Gutiérrez-Lamus, Rafael O. De Sá Apr 2019

Presence And Distribution Of Leptodactylus Guianensis Heyer And De Sa, 2011 In Colombia: Comparisons With Other Species In The L. Latrans Group., Mariela Osorno Muñoz, Doris L. Gutiérrez-Lamus, Rafael O. De Sá

Biology Faculty Publications

Leptodactylus guianensis is reported for the first time for Colombia along with a distributional map of the species. The species is the fifth species of the L. latransspecies group documented in the country. Males possess a single, conical and slightly chisel-shaped thumb spine; only three species in the group have a single thumb spine. In collections, specimens of L. guianensis are misidentified as L. macrosternum, L. latrans or L. bolivianus. We provide morphological, colouration and habitat descriptions for where the species occurs in Colombia.


Creative Citizen Science Illuminates Complex Ecological Responses To Climate Change, Abraham J. Miller-Rushing, Amanda S. Gallinat, Richard B. Primack Jan 2019

Creative Citizen Science Illuminates Complex Ecological Responses To Climate Change, Abraham J. Miller-Rushing, Amanda S. Gallinat, Richard B. Primack

Biology Faculty Publications

Climate change is causing the timing of key behaviors (i.e., phenology) to shift differently across trophic levels and among some interacting organisms (e.g., plants and pollinators, predators and prey), suggesting that interactions among species are being disrupted (1, 2). Studying the phenology of interactions, however, is difficult, which has limited researchers’ ability to zero in on changes in specific interactions or on the consequences of mismatches. In PNAS, Hassall et al. (3) use a combination of citizen science techniques to investigate the effects of climate change on dozens of specific interactions. They focus on a Batesian mimicry complex involving stinging …


Leptodactylus Validus Garman, 1888 In Colombia: Its Distribution And Identification, Andres R. Acosta Galvis, Rafael O. De Sá Jan 2018

Leptodactylus Validus Garman, 1888 In Colombia: Its Distribution And Identification, Andres R. Acosta Galvis, Rafael O. De Sá

Biology Faculty Publications

Leptodactylus validus is reported for the first time for Colombia, corresponding to the tenth species of the L. melanonotus species group occurring in the country. In collections, all L. validus specimens were identified as L. colombiensis. Morphological, coloration, and ecological characters are provided to differentiate the two species in Colombia. Furthermore, the distribution of L. validus is expanded based on the examination of specimens in both collections and literature records. In addition, the advertisement call of L. validus from Colombia is compared with those reported for other continental and insular populations; the calls are slightly more similar to those …


The Tao Of Open Science For Ecology, S. E. Hampton, S. S. Anderson, S. C. Bagby, C. Gries, X. Han, E. M. Hart, M. B. Jones, W. C. Lenhardt, A. Macdonald, W. K. Michener, J. Mudge, A. Pourmokhtarian, M. P. Schildhauer, K. H. Woo, Naupaka B. Zimmerman Jan 2015

The Tao Of Open Science For Ecology, S. E. Hampton, S. S. Anderson, S. C. Bagby, C. Gries, X. Han, E. M. Hart, M. B. Jones, W. C. Lenhardt, A. Macdonald, W. K. Michener, J. Mudge, A. Pourmokhtarian, M. P. Schildhauer, K. H. Woo, Naupaka B. Zimmerman

Biology Faculty Publications

The field of ecology is poised to take advantage of emerging technologies that facilitate the gathering, analyzing, and sharing of data, methods, and results. The concept of transparency at all stages of the research process, coupled with free and open access to data, code, and papers, constitutes “open science.” Despite the many benefits of an open approach to science, a number of barriers to entry exist that may prevent researchers from embracing openness in their own work. Here we describe several key shifts in mindset that underpin the transition to more open science. These shifts in mindset include thinking about …


Strong Self-Limitation Promotes The Persistence Ofrare Species, G. M. Yenni, P. B. Adler, S.K. Morgan Ernest Jan 2012

Strong Self-Limitation Promotes The Persistence Ofrare Species, G. M. Yenni, P. B. Adler, S.K. Morgan Ernest

Biology Faculty Publications

Theory has recognized a combination of niche and neutral processes each contributing, with varying importance, to species coexistence. However, long-term persistence of rare species has been difficult to produce in trait-based models of coexistence that incorporate stochastic dynamics, raising questions about how rare species persist despite such variability. Following recent evidence that rare species may experience significantly different population dynamics than dominant species, we use a plant community model to simulate the effect of disproportionately strong negative frequency dependence on the long-term persistence of the rare species in a simulated community. This strong self-limitation produces long persistence times for the …


Species Compositionand Abundance Of Mammalian Communities, K. M. Thibault, S. R. Supp, M. Griffin, Ethan P. White, S.K. Morgan Ernest Jan 2011

Species Compositionand Abundance Of Mammalian Communities, K. M. Thibault, S. R. Supp, M. Griffin, Ethan P. White, S.K. Morgan Ernest

Biology Faculty Publications

Ecologists have long sought to understand the mechanisms underlying the assembly and structure of communities. Such understanding is relevant to both basic science and conservation-related issues. The macroecological approach to this problem involves asking scientific questions using a large number of communities in order to elucidate generalities in pattern and process. Such analyses are typically conducted using a substantial amount of data from a particular taxonomic group across a diversity of systems. Large community databases are available for a number of taxa, but no publicly available database exists for mammals. Given the logistical challenges of collecting such data de novo, …


On The Use Of Log-Transformation Vs. Nonlinear Regression For Analyzing Biological Power-Laws, Xiao Xiao, Ethan P. White, M. B. Hooten, Susan L. Durham Jan 2011

On The Use Of Log-Transformation Vs. Nonlinear Regression For Analyzing Biological Power-Laws, Xiao Xiao, Ethan P. White, M. B. Hooten, Susan L. Durham

Biology Faculty Publications

Power-law relationships are among the most well-studied functional relationships in biology. Recently the common practice of fitting power-laws using linear regression on log-transformed data (LR) has been criticized, calling into question the conclusions of hundreds of studies. It has been suggested that nonlinear regression (NLR) is preferable, but no rigorous comparison of these two methods has been conducted. Using Monte Carlo simulations we demonstrate that the error distribution determines which method performs better, with LR better characterizing data with multiplicative lognormal error and NLR better characterizing data with additive, homoscedastic, normal error. Analysis of 471 biological power-laws shows that both …


Osteology, Natural History Notes, And Phylogenetic Relationships Of The Poorly Known Caribbean Frog Leptodactylus Nesiotus (Anura, Leptodactylidae), María Laura Ponssa, Michael J. Jowers, Rafael O. De Sá Oct 2010

Osteology, Natural History Notes, And Phylogenetic Relationships Of The Poorly Known Caribbean Frog Leptodactylus Nesiotus (Anura, Leptodactylidae), María Laura Ponssa, Michael J. Jowers, Rafael O. De Sá

Biology Faculty Publications

The Leptodactylus melanonotus group consists of 15 species, but references to skeletal characters are available for only three species: L. leptodactyloides, L. melanonotus, and L. diedrus. Leptodactylus nesiotus is a member of the melanonotus group known only from the type locality, Bonasse swamp, on the Southwestern peninsula of Trinidad, Trinidad and Tobago. This species has been categorized as vulnerable given its restricted distribution. Herein, we report the adult osteology of L. nesiotus, the skeletal characters are compared with the available data from other Leptodactylus species. A phylogenetic analysis recovers a paraphyletic L. melanonotus group relative to the L. …


Granite Rock Outcrops: An Extreme Environment For Soil Nematodes?, Erin Austin, Katharine Semmens, Charles Parsons, Amy M. Treonis Mar 2009

Granite Rock Outcrops: An Extreme Environment For Soil Nematodes?, Erin Austin, Katharine Semmens, Charles Parsons, Amy M. Treonis

Biology Faculty Publications

We studied soil nematode communities from the surface of granite flatrock outcrops in the eastern Piedmont region of the United States. The thin soils that develop here experience high light intensity and extreme fluctuations in temperature and moisture and host unique plant communities. We collected soils from outcrop microsites in Virginia (VA) and North Carolina (NC) in various stages of succession (Primitive, Minimal, and Mature) and compared soil properties and nematode communities to those of adjacent forest soils. Nematodes were present in most outcrop soils, with densities comparable to forest soils (P > 0.05). Nematode communities in Mature and Minimal soils …


Cuscuta Jepsonii (Convolvulaceae): An Invasive Weed Or An Extinct Endemic?, Mihai Costea, Saša Stefanović Jan 2009

Cuscuta Jepsonii (Convolvulaceae): An Invasive Weed Or An Extinct Endemic?, Mihai Costea, Saša Stefanović

Biology Faculty Publications

Despite their ecological significance, parasitic plants face more conservation challenges than do autotrophic plants. This is especially true for the groups that include weedy or invasive species such as Cuscuta. While approximately half of the Cuscuta (dodders) species may require conservation measures, the genus as a whole is sometimes posted on governmental lists of noxious or quarantine weeds. Our study challenges this stereotype and uses the case of C. jepsonii (Jepson’s dodder) to illustrate the precarious biodiversity and conservation status faced by many dodder species. Until now, Jepson’s dodder has been known only from its type collection. Consequently, its …


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 …


The Biology Of Canadian Weeds. 131. Polygonum Aviculare L., Mihai Costea, François J. Tardif Apr 2005

The Biology Of Canadian Weeds. 131. Polygonum Aviculare L., Mihai Costea, François J. Tardif

Biology Faculty Publications

A review and assessment of biological information as well as personal data are provided for Polygonum aviculare in Canada. The species has been revised taxonomically and the six subspecies that occur in Canada are presented. Three of the subspecies, P. aviculare subsp. aviculare, P. aviculare subsp. neglectum and P. aviculare subsp. depressum are weeds introduced to Canada from Europe. A fourth subspecies, P. aviculare subsp. buxiforme is apparently native to North America. The geographical distribution of the latter four subspecies is very wide. Plants exhibit a high phenotypic plasticity and genetic variability, and they easily adapt to a multitude …


On The Enigmatic Distribution Of The Honduran Endemic Leptodactylus Silvanimbus (Amphibia: Anura: Lep Todactylidae), W. Ronald Heyer, Rafael O. De Sá, Sarah Muller Jan 2005

On The Enigmatic Distribution Of The Honduran Endemic Leptodactylus Silvanimbus (Amphibia: Anura: Lep Todactylidae), W. Ronald Heyer, Rafael O. De Sá, Sarah Muller

Biology Faculty Publications

Most species of the frog genus Leptodactylus occur in South America, and all authors who have treated the zoogeography of the genus have concluded that it originated somewhere in South America (e.g., Savage 1982). Savage (1982,518) summarized the historical herpetofaunal units of the Neotropics as follows: "All evidence points to an ancient contiguity and essential similarity of a generalized tropical herpetofauna that ranged over tropical North, Middle, and most of South America in Cretaceous-Paleocene times. Descendents of this fauna are represented today by the South and Middle American tracks (Elements). To the north of this fauna ranged a subtropical-temperate Laurasian …


The Challenge Of Environmental Protection, Jennifer Mattei Jan 2005

The Challenge Of Environmental Protection, Jennifer Mattei

Biology Faculty Publications

Connecticut is in the midst of a demographic transition to a period of lower population growth. These demographic changes will help check the pressures exerted on the state's natural resources by population growth. Water, air, soil, energy sources, food, fisheries, forests, and biodiversity are common pool resources upon which we depend in ways that transcend political boundaries. Those governing Connecticut should help turn the state into a model of how to manage natural resources by halting forest fragmentation, reducing pollution, and promoting environmental science education.


Two-Phase Species-Time Relationships In North American Land Birds, Ethan P. White Jan 2004

Two-Phase Species-Time Relationships In North American Land Birds, Ethan P. White

Biology Faculty Publications

The species-time relationship (STR) is a macroecological pattern describing the increase in the observed species richness with the length of time censused. Understanding STRs is important for understanding the ecological processes underlying temporal turnover and species richness. However, accurate characterization of the STR has been hampered by the influence of sampling. I analyzed species-time relationships for 521 breeding bird survey communities. I used a model of sampling effects to demonstrate that the increase in richness was not due exclusively to sampling. I estimated the time scale at which ecological processes became dominant over sampling effects using a two-phase model combining …


The Biology Of Canadian Weeds. 126. Amaranthus Albus L., A. Blitoides S. Watson And A. Blitum L., Mihai Costea, François J. Tardif Oct 2003

The Biology Of Canadian Weeds. 126. Amaranthus Albus L., A. Blitoides S. Watson And A. Blitum L., Mihai Costea, François J. Tardif

Biology Faculty Publications

A review of biological information is provided for three species of the genus Amaranthus: A. albus L., A. blitoides S. Watson and A. blitum L. The last species has been revised taxonomically and a new subspecies for Canada is presented—A. blitum subsp. emarginatus (Moq. ex Uline & Bray) Carretero, Munoz Garmendia & Pedrol. Amaranthus albus and A. blitoides are native to the U.S.A. and introduced to Canada. Both species are annual ruderal and agrestal weeds. During the past 100 yr the two species have spread across most provinces of Canada, but the greatest frequency and abundance have been …


Review Of The Nature Of Nebraska: Ecology And Biodiversity Paul A. Johnsgard, L. Lareesa Wolfenbarger Jan 2003

Review Of The Nature Of Nebraska: Ecology And Biodiversity Paul A. Johnsgard, L. Lareesa Wolfenbarger

Biology Faculty Publications

As a newcomer to Nebraska and someone learning the natural history of this place, I thoroughly enjoyed The Nature of Nebraska. More consequentially, the book will serve as a valuable resource for longtime naturalists, teachers, and others who want to learn about Nebraska's natural history.

Opening with a discussion of geology and ecology, Johnsgard offers a broad overview of Nebraska's ecological diversity, intertwining material on the natural forces that have historically dominated the Plains with a discussion of the anthropogenic forces currently altering the region's unique ecological nature. Approximately half of the book is devoted to more specific descriptions …


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.


What Are Squirrels Hiding, Michael Steele, Peter D. Smallwood Jan 1994

What Are Squirrels Hiding, Michael Steele, Peter D. Smallwood

Biology Faculty Publications

The half-eaten acorns of squirrels are clues to their complex relationship with oaks. The special relationship between squirrels and acorns is examined.


Individualistic Perspectives On Plant Competition, Nancy J. Huntly Jan 1992

Individualistic Perspectives On Plant Competition, Nancy J. Huntly

Biology Faculty Publications

No abstract provided.