Background/Question/Methods Throughout human history, stories have been used to entertain, educat... more Background/Question/Methods Throughout human history, stories have been used to entertain, educate, learn, and connect. Building on previous success in using original short stories to engage undergraduate students in ecological science, we devised an innovative approach to simultaneously teach ecology and creative writing. We test the hypothesis that by engaging students in the process of writing and analyzing ecological fiction while simultaneously teaching them fundamental ecological principles, students will gain a deeper appreciation and understanding of science and the humanities. We (Skillen, an English professor, and Bowne, a Biology professor) collaborated to create and teach a course titled “Ecology in Short Fiction” that satisfies both “Creative Expression” and “Natural and Physical Sciences” general education requirements at Elizabethtown College. We designed the course around seven themes (Science and the Humanities, Energy and Evolution, Individual Behavior, Populations...
Background/Question/Methods The population structure of freshwater turtle species has been of int... more Background/Question/Methods The population structure of freshwater turtle species has been of interest as several researchers are finding biased age and sex ratios. These findings are often attributed to anthropogenic changes in the landscape. A high concentration of roads near turtle nesting sites may, for example, selectively increase mortality of adult females, leading to a male-biased population. Increased predation of nests caused by a high density of predators that flourish in human-dominated landscapes may reduce juvenile recruitment and cause an adult-biased population. To determine if the freshwater turtle population in Elizabethtown, Pennsylvania is biased, we conducted a mark-recapture study of painted turtles (Chrysemys picta) in three ponds on the campus of Elizabethtown College in the fall of 2009, 2010, and 2011. We placed hoop traps in each pond for two consecutive days and marked, measured, and then released any captured turtles. Results/Conclusions The total number...
The spatial and temporal dimensions of the insurgency in Iraq have not been adequately analyzed. ... more The spatial and temporal dimensions of the insurgency in Iraq have not been adequately analyzed. Attacks by the insurgents are clearly not equally likely in all parts of Iraq, but these spatial differences are typically reported at the course scale of provinces, large cities, or quasi-geographic areas such as the "Sunni Triangle". The emphasis has rather been placed on spatial summary metrics such as those proposed by the Bush administration (e.g., number of actionable intelligence tips, number of contacts initiated by Coalition forces, number of Iraqi army units 1 ) or more widely used in the popular media (e.g., numbers of Coalition or Iraqi civilian casualties). These summary metrics give an incomplete indication of the state of affairs in Iraq because they do not convey how insurgent activity changes over time and space. The amount of territory under enemy influence has always been of vital concern and should be even under the non-traditional warfare of insurgency.
ABSTRACT The use of terrestrial habitat by freshwater turtles is receiving increased attention by... more ABSTRACT The use of terrestrial habitat by freshwater turtles is receiving increased attention by herpetologists, driven in part by conservation efforts to protect critical upland habitat. I report on a high degree of non-nesting terrestrial activity by Chrysemys picta in Virginia. During a three-year project, 60 individual adult turtles were followed by radiotelemetry, primarily during the summer, with 22 of them being detected on land. Fifteen turtles dispersed overland at distances up to 3300 m, two turtles nested, four turtles aestivated on land for a mean of 34 days, and an adult male overwintered on land for approximately 290 days. Terrestrial activity was evidently prompted by drying of the home ponds. Most available upland habitats were used, with slight preferences by dispersing turtles for wooded habitats and by aestivating turtles for non-wooded habitats. Aestivation on land by C. picta has rarely been reported but may be fairly common during periods of drought. Overwintering on land by adult C. picta has not been reported and will require additional research to explain the physiological responses needed to survive. This study underscores the importance of upland habitat in the life history and conservation of freshwater turtles.
Question: Sampling biases influence the estimation of sex ratio in species with environmental sex... more Question: Sampling biases influence the estimation of sex ratio in species with environmental sex determination (ESD). Are these biases the sole reason for the apparent sex ratio in such species? Methods: Over a 6-year period, we studied maturing painted turtles (Chrysemys picta) through mark and recapture in a complex of ponds in northern Virginia. To avoid the biases associated with the measurement of primary and adult sex ratios, we monitored individuals over multiple years and measured sex-specific capture and survival rates. Results: We observed a significant female bias that cannot be attributed to climatic variance or differential survival, capture, or age at maturity. Conclusions: The observed female bias cannot be explained by existing evolutionary models and is consistent with a lag in evolutionary response to the loss of male-producing environments resulting from human influences on vegetation cover.
Background/Question/Methods Global climate change, like most environmental topics, is so complex ... more Background/Question/Methods Global climate change, like most environmental topics, is so complex that undergraduate students have difficulty understanding the concept. But with a topic of such importance, a student’s learning outcome should be more than understanding, it should be internalization. I suggest that a narrative, fictional in concept but scientific in content, is an effective way to achieve this outcome. I report on my success in using short stories to achieve comprehension and personal appreciation for environmental topics in a non-majors science course. Each entertaining story is specifically written for an undergraduate audience. “Henry Ford Hated Glaciers” is the tale of roommates arguing over the causes and solutions to climate change. After reading the story, students embark on an entrepreneurial mission to develop a product that sequesters carbon. In “Talking Turkey” a student causes a stir at her Thanksgiving dinner when she announces to her family that she has b...
Background/Question/Methods Turtles inspire fascination and fondness in many people. Through the ... more Background/Question/Methods Turtles inspire fascination and fondness in many people. Through the Ecological Research as Education Network (EREN), we took advantage of this inherent interest in turtles to introduce undergraduate students to vertebrate ecology while also determining how urbanization impacts turtle populations. An increase in urbanization is predicted to increase mortality rates of adult female turtles during nesting movements. If true, turtle populations should become more male-biased as urbanization increases. Faculty and students at over twenty-five institutions, mostly in the eastern United States, participated in the EREN pilot project TurtlePop with the dual goals of collecting data to test this hypothesis and providing a unique, collaborative, and authentic research opportunity for students. Participants conducted a mark-recapture study in 2012 and 2013 in one or more ponds using uniform protocols developed specifically for this project. Participants were traine...
EcoEd Digital Library (http://esa.org/ecoed) Title: Talking Turkey: Using a short story to facili... more EcoEd Digital Library (http://esa.org/ecoed) Title: Talking Turkey: Using a short story to facilitate learning and appreciation of energy flows through ecosystems Author(s): Abstract: Human beings are storytellers. Through stories, we entertain, educate, learn, and connect. This exercise uses the universality of storytelling to engage undergraduate students in ecological science. Students read a fictional narrative that connects scientific principles of ecology to their daily life. The narrative helps students become more personally engaged in the scientific material and more interested in analyzing and evaluating the role of science in society. The submitted story "Talking Turkey" is about a college student's interactions with her family when she informs them at Thanksgiving of her decision to stop eating meat for ecological, not ethical reasons. To appreciate her decision, students have to understand food chains, energy flows, the first and second laws of thermodynam...
ABSTRACT Soil carbon dioxide efflux is impacted by urbanization but few studies have directly exa... more ABSTRACT Soil carbon dioxide efflux is impacted by urbanization but few studies have directly examined it in contrasting human-dominated land uses. We tested the hypothesis that soil carbon dioxide efflux would be greater in residential lawns than corn fields in Lancaster County, PA, by measuring soil carbon dioxide efflux, soil temperature, and soil moisture once a week for 10 wk in the fall of 2011. Soil carbon dioxide efflux occurring in residential lawns was signifi cantly higher (F1,6 = 7.46, p = 0.034) than the levels in corn (Zea mays L.) fields for the duration of the study. Soil carbon dioxide efflux significantly decreased over time in both land-use types (F9,54 = 37.34, p < 0.001). Soil temperature, soil moisture, and land-use type significantly contributed to the efflux (R2 = 0.744, F3,76 = 73.443, p < 0.001). Higher soil temperatures in residential lawns were attributed to an urban heat island. Our results suggest converting agricultural land to residential developments could increase soil carbon dioxide release per unit area of soil, especially if urbanization increases local soil temperatures.
The movement path made by an organism in search of a resource contributes strongly to the success... more The movement path made by an organism in search of a resource contributes strongly to the success of that search. But are similar search strategies used at very different spatial scales? Using painted turtles as our model organism, we ask (1) whether terrestrial search paths, both shape and rate, are similar at small (30 m) and large (O500 m) spatial scales, (2) whether those search paths are linear, and what environmental conditions affect the shape of the search path? We found that movement paths at both small and large spatial scales were nearly straight and statistically indistinguishable from one another. The mean turning angles at small and large spatial scales were statistically similar and were best represented by an angle of 1.8 . Net displacement rates were, however, quite different between small-and large-scale paths. At small spatial scales, path shape and movement rate were most strongly affected by cloud cover and turtle size, respectively. Our results indicate that the shape of a search path is consistent over small and large spatial scales and gives support for extrapolating larger-scale path shape from small-scale observations. Net displacement rates, however, were scale dependent and thus caution must be taken in using behaviours detected at small scales to predict movement rates over larger areas. An unexpected result was that painted turtles did not follow drainages in search of aquatic habitat in this study system.
We discuss the benefits that a collaborative research network, a group of faculty from different ... more We discuss the benefits that a collaborative research network, a group of faculty from different institutions who jointly conduct a research project, can have on undergraduate research (UR) by enhancing the diversity and significance of projects and by improving student motivation and breadth of learning. The main example used is the Ecological Research as Education Network (EREN), founded in 2010 to enhance undergraduate research in ecology at primarily undergraduate institutions (PUIs) by (1) providing networking and collaborative research opportunities for both faculty and students and (2) developing free educational resources. EREN comprises about 280 ecology faculty and staff nationally and has facilitated development of nine continental-scale, collaborative research projects.
Background/Question/Methods In order to improve the ecosystem services provided by a stream in an... more Background/Question/Methods In order to improve the ecosystem services provided by a stream in an agricultural landscape, a consortium of scientists, state and federal officials, and environmental consultants are conducting an experimental stream restoration project in which legacy sediments are removed. The intent is to return Big Spring Run, PA to a condition similar to that of pre-European settlement. The restoration occurred in fall of 2011 in which 1500 m3 of legacy sediment were removed to restore 1000 m of stream. Our study focuses on the pre-restoration (spring/summer 2010, 2011) and post-restoration (spring/summer 2012) status of amphibian populations. We captured salamanders in each of the three branches being restored (Main, West, and East) using litterbags and kick nets in 2010 and additionally used dip nets and manual capture in 2011. In 2011, we also sampled Kennel branch, a segment that is not part of the restoration and thus serves as a control. To identify the prese...
Background/Question/Methods Tiered learning was a mainstay of one-room school houses, yet this ap... more Background/Question/Methods Tiered learning was a mainstay of one-room school houses, yet this approach is under-used today in higher education. Our study demonstrates how a tiered dynamic can produce positive outcomes at each level of learning and contribute to scientific advancement. We involved high school and undergraduate students in a project examining the large-scale distribution of antibiotic resistance in soil bacteria. Prior to and during the study period, we mentored undergraduate students in the leadership and operational skills needed to conduct an ecological research project, including appropriate techniques, planning, and support. The undergraduates served as team leaders in direct supervision of high school students, who were competitively selected by the Earthwatch Institute. Results/Conclusions The high school students actively participated in the process of science by collecting, processing, and analyzing samples. By staying with the high school students in reside...
The rapid evolution of antibiotic resistance in bacteria is one of the most pressing public healt... more The rapid evolution of antibiotic resistance in bacteria is one of the most pressing public health problems in the nation. According to the Center for Disease Control, over 70% of the bacteria that cause hospital-acquired infections are resistant to at least one commonly prescribed drug. The fight against antibiotic resistance is primarily focused on clinical settings. Antibiotic resistant bacteria are, however, found in the environment as well. Intense use of antibiotics for livestock and other agricultural practices contributes to this pool of resistance. But not all cases of resistance are caused by direct use of antibiotics. Many metals, including mercury, lead, cadmium, cobalt, nickel, copper, and vanadium, are often correlated with antibiotic resistance. Naturally occurring resistance also stems from interactions between microbes in the environment. Recent research highlights the need to understand patterns of antibiotic resistance in the environment, as well as in clinical se...
We used published data of individuals moving among habitat patches to answer questions pertaining... more We used published data of individuals moving among habitat patches to answer questions pertaining to frequency of interpatch movements and subsequent effects on population dynamics. A review of 415 published articles produced data for 89 species-system combinations where movements were recorded in sufficient detail to include in our analysis. The percentage of individuals in a population that moved among habitat patches ranged from 0.00 to 93.00%, with a mean of 16.84%. Scaling this statistic by generation time yielded a mean movement rate of 15.45 Ϯ 3.27% per generation. The relatively low movement rates suggest that subpopulations, except those of effects of interpatch movement. Of these, thirty-three studies yielded population effects on 34 individual species in 45 species-systems. They reported movement having a positive effect 28 times, a negative effect twice and a neutral effect 14 times. Despite its importance, relatively few studies document rates of interpatch movement and far fewer determine population level consequences of these movements. This deficiency limits our ability to understand the dynamics of spatially structured populations and apply that knowledge to conservation efforts.
Gary W. Barrett John D. Peles Institute of Ecology Savannah River Ecology Laboratory The Universi... more Gary W. Barrett John D. Peles Institute of Ecology Savannah River Ecology Laboratory The University of Georgia The University of Georgia Athens, GA 30602 Aiken, SC 29802 USA USA Cover illustration: Photograph of the Ecology Research Center, Miami University, Oxford, Ohio, ...
One of the most popular approaches for maintaining populations and conserving biodiversity in fra... more One of the most popular approaches for maintaining populations and conserving biodiversity in fragmented landscapes is to retain or create corridors that connect otherwise isolated habitat patches. Working in large-scale, experimental landscapes in which open-habitat patches ...
Background/Question/Methods Throughout human history, stories have been used to entertain, educat... more Background/Question/Methods Throughout human history, stories have been used to entertain, educate, learn, and connect. Building on previous success in using original short stories to engage undergraduate students in ecological science, we devised an innovative approach to simultaneously teach ecology and creative writing. We test the hypothesis that by engaging students in the process of writing and analyzing ecological fiction while simultaneously teaching them fundamental ecological principles, students will gain a deeper appreciation and understanding of science and the humanities. We (Skillen, an English professor, and Bowne, a Biology professor) collaborated to create and teach a course titled “Ecology in Short Fiction” that satisfies both “Creative Expression” and “Natural and Physical Sciences” general education requirements at Elizabethtown College. We designed the course around seven themes (Science and the Humanities, Energy and Evolution, Individual Behavior, Populations...
Background/Question/Methods The population structure of freshwater turtle species has been of int... more Background/Question/Methods The population structure of freshwater turtle species has been of interest as several researchers are finding biased age and sex ratios. These findings are often attributed to anthropogenic changes in the landscape. A high concentration of roads near turtle nesting sites may, for example, selectively increase mortality of adult females, leading to a male-biased population. Increased predation of nests caused by a high density of predators that flourish in human-dominated landscapes may reduce juvenile recruitment and cause an adult-biased population. To determine if the freshwater turtle population in Elizabethtown, Pennsylvania is biased, we conducted a mark-recapture study of painted turtles (Chrysemys picta) in three ponds on the campus of Elizabethtown College in the fall of 2009, 2010, and 2011. We placed hoop traps in each pond for two consecutive days and marked, measured, and then released any captured turtles. Results/Conclusions The total number...
The spatial and temporal dimensions of the insurgency in Iraq have not been adequately analyzed. ... more The spatial and temporal dimensions of the insurgency in Iraq have not been adequately analyzed. Attacks by the insurgents are clearly not equally likely in all parts of Iraq, but these spatial differences are typically reported at the course scale of provinces, large cities, or quasi-geographic areas such as the "Sunni Triangle". The emphasis has rather been placed on spatial summary metrics such as those proposed by the Bush administration (e.g., number of actionable intelligence tips, number of contacts initiated by Coalition forces, number of Iraqi army units 1 ) or more widely used in the popular media (e.g., numbers of Coalition or Iraqi civilian casualties). These summary metrics give an incomplete indication of the state of affairs in Iraq because they do not convey how insurgent activity changes over time and space. The amount of territory under enemy influence has always been of vital concern and should be even under the non-traditional warfare of insurgency.
ABSTRACT The use of terrestrial habitat by freshwater turtles is receiving increased attention by... more ABSTRACT The use of terrestrial habitat by freshwater turtles is receiving increased attention by herpetologists, driven in part by conservation efforts to protect critical upland habitat. I report on a high degree of non-nesting terrestrial activity by Chrysemys picta in Virginia. During a three-year project, 60 individual adult turtles were followed by radiotelemetry, primarily during the summer, with 22 of them being detected on land. Fifteen turtles dispersed overland at distances up to 3300 m, two turtles nested, four turtles aestivated on land for a mean of 34 days, and an adult male overwintered on land for approximately 290 days. Terrestrial activity was evidently prompted by drying of the home ponds. Most available upland habitats were used, with slight preferences by dispersing turtles for wooded habitats and by aestivating turtles for non-wooded habitats. Aestivation on land by C. picta has rarely been reported but may be fairly common during periods of drought. Overwintering on land by adult C. picta has not been reported and will require additional research to explain the physiological responses needed to survive. This study underscores the importance of upland habitat in the life history and conservation of freshwater turtles.
Question: Sampling biases influence the estimation of sex ratio in species with environmental sex... more Question: Sampling biases influence the estimation of sex ratio in species with environmental sex determination (ESD). Are these biases the sole reason for the apparent sex ratio in such species? Methods: Over a 6-year period, we studied maturing painted turtles (Chrysemys picta) through mark and recapture in a complex of ponds in northern Virginia. To avoid the biases associated with the measurement of primary and adult sex ratios, we monitored individuals over multiple years and measured sex-specific capture and survival rates. Results: We observed a significant female bias that cannot be attributed to climatic variance or differential survival, capture, or age at maturity. Conclusions: The observed female bias cannot be explained by existing evolutionary models and is consistent with a lag in evolutionary response to the loss of male-producing environments resulting from human influences on vegetation cover.
Background/Question/Methods Global climate change, like most environmental topics, is so complex ... more Background/Question/Methods Global climate change, like most environmental topics, is so complex that undergraduate students have difficulty understanding the concept. But with a topic of such importance, a student’s learning outcome should be more than understanding, it should be internalization. I suggest that a narrative, fictional in concept but scientific in content, is an effective way to achieve this outcome. I report on my success in using short stories to achieve comprehension and personal appreciation for environmental topics in a non-majors science course. Each entertaining story is specifically written for an undergraduate audience. “Henry Ford Hated Glaciers” is the tale of roommates arguing over the causes and solutions to climate change. After reading the story, students embark on an entrepreneurial mission to develop a product that sequesters carbon. In “Talking Turkey” a student causes a stir at her Thanksgiving dinner when she announces to her family that she has b...
Background/Question/Methods Turtles inspire fascination and fondness in many people. Through the ... more Background/Question/Methods Turtles inspire fascination and fondness in many people. Through the Ecological Research as Education Network (EREN), we took advantage of this inherent interest in turtles to introduce undergraduate students to vertebrate ecology while also determining how urbanization impacts turtle populations. An increase in urbanization is predicted to increase mortality rates of adult female turtles during nesting movements. If true, turtle populations should become more male-biased as urbanization increases. Faculty and students at over twenty-five institutions, mostly in the eastern United States, participated in the EREN pilot project TurtlePop with the dual goals of collecting data to test this hypothesis and providing a unique, collaborative, and authentic research opportunity for students. Participants conducted a mark-recapture study in 2012 and 2013 in one or more ponds using uniform protocols developed specifically for this project. Participants were traine...
EcoEd Digital Library (http://esa.org/ecoed) Title: Talking Turkey: Using a short story to facili... more EcoEd Digital Library (http://esa.org/ecoed) Title: Talking Turkey: Using a short story to facilitate learning and appreciation of energy flows through ecosystems Author(s): Abstract: Human beings are storytellers. Through stories, we entertain, educate, learn, and connect. This exercise uses the universality of storytelling to engage undergraduate students in ecological science. Students read a fictional narrative that connects scientific principles of ecology to their daily life. The narrative helps students become more personally engaged in the scientific material and more interested in analyzing and evaluating the role of science in society. The submitted story "Talking Turkey" is about a college student's interactions with her family when she informs them at Thanksgiving of her decision to stop eating meat for ecological, not ethical reasons. To appreciate her decision, students have to understand food chains, energy flows, the first and second laws of thermodynam...
ABSTRACT Soil carbon dioxide efflux is impacted by urbanization but few studies have directly exa... more ABSTRACT Soil carbon dioxide efflux is impacted by urbanization but few studies have directly examined it in contrasting human-dominated land uses. We tested the hypothesis that soil carbon dioxide efflux would be greater in residential lawns than corn fields in Lancaster County, PA, by measuring soil carbon dioxide efflux, soil temperature, and soil moisture once a week for 10 wk in the fall of 2011. Soil carbon dioxide efflux occurring in residential lawns was signifi cantly higher (F1,6 = 7.46, p = 0.034) than the levels in corn (Zea mays L.) fields for the duration of the study. Soil carbon dioxide efflux significantly decreased over time in both land-use types (F9,54 = 37.34, p < 0.001). Soil temperature, soil moisture, and land-use type significantly contributed to the efflux (R2 = 0.744, F3,76 = 73.443, p < 0.001). Higher soil temperatures in residential lawns were attributed to an urban heat island. Our results suggest converting agricultural land to residential developments could increase soil carbon dioxide release per unit area of soil, especially if urbanization increases local soil temperatures.
The movement path made by an organism in search of a resource contributes strongly to the success... more The movement path made by an organism in search of a resource contributes strongly to the success of that search. But are similar search strategies used at very different spatial scales? Using painted turtles as our model organism, we ask (1) whether terrestrial search paths, both shape and rate, are similar at small (30 m) and large (O500 m) spatial scales, (2) whether those search paths are linear, and what environmental conditions affect the shape of the search path? We found that movement paths at both small and large spatial scales were nearly straight and statistically indistinguishable from one another. The mean turning angles at small and large spatial scales were statistically similar and were best represented by an angle of 1.8 . Net displacement rates were, however, quite different between small-and large-scale paths. At small spatial scales, path shape and movement rate were most strongly affected by cloud cover and turtle size, respectively. Our results indicate that the shape of a search path is consistent over small and large spatial scales and gives support for extrapolating larger-scale path shape from small-scale observations. Net displacement rates, however, were scale dependent and thus caution must be taken in using behaviours detected at small scales to predict movement rates over larger areas. An unexpected result was that painted turtles did not follow drainages in search of aquatic habitat in this study system.
We discuss the benefits that a collaborative research network, a group of faculty from different ... more We discuss the benefits that a collaborative research network, a group of faculty from different institutions who jointly conduct a research project, can have on undergraduate research (UR) by enhancing the diversity and significance of projects and by improving student motivation and breadth of learning. The main example used is the Ecological Research as Education Network (EREN), founded in 2010 to enhance undergraduate research in ecology at primarily undergraduate institutions (PUIs) by (1) providing networking and collaborative research opportunities for both faculty and students and (2) developing free educational resources. EREN comprises about 280 ecology faculty and staff nationally and has facilitated development of nine continental-scale, collaborative research projects.
Background/Question/Methods In order to improve the ecosystem services provided by a stream in an... more Background/Question/Methods In order to improve the ecosystem services provided by a stream in an agricultural landscape, a consortium of scientists, state and federal officials, and environmental consultants are conducting an experimental stream restoration project in which legacy sediments are removed. The intent is to return Big Spring Run, PA to a condition similar to that of pre-European settlement. The restoration occurred in fall of 2011 in which 1500 m3 of legacy sediment were removed to restore 1000 m of stream. Our study focuses on the pre-restoration (spring/summer 2010, 2011) and post-restoration (spring/summer 2012) status of amphibian populations. We captured salamanders in each of the three branches being restored (Main, West, and East) using litterbags and kick nets in 2010 and additionally used dip nets and manual capture in 2011. In 2011, we also sampled Kennel branch, a segment that is not part of the restoration and thus serves as a control. To identify the prese...
Background/Question/Methods Tiered learning was a mainstay of one-room school houses, yet this ap... more Background/Question/Methods Tiered learning was a mainstay of one-room school houses, yet this approach is under-used today in higher education. Our study demonstrates how a tiered dynamic can produce positive outcomes at each level of learning and contribute to scientific advancement. We involved high school and undergraduate students in a project examining the large-scale distribution of antibiotic resistance in soil bacteria. Prior to and during the study period, we mentored undergraduate students in the leadership and operational skills needed to conduct an ecological research project, including appropriate techniques, planning, and support. The undergraduates served as team leaders in direct supervision of high school students, who were competitively selected by the Earthwatch Institute. Results/Conclusions The high school students actively participated in the process of science by collecting, processing, and analyzing samples. By staying with the high school students in reside...
The rapid evolution of antibiotic resistance in bacteria is one of the most pressing public healt... more The rapid evolution of antibiotic resistance in bacteria is one of the most pressing public health problems in the nation. According to the Center for Disease Control, over 70% of the bacteria that cause hospital-acquired infections are resistant to at least one commonly prescribed drug. The fight against antibiotic resistance is primarily focused on clinical settings. Antibiotic resistant bacteria are, however, found in the environment as well. Intense use of antibiotics for livestock and other agricultural practices contributes to this pool of resistance. But not all cases of resistance are caused by direct use of antibiotics. Many metals, including mercury, lead, cadmium, cobalt, nickel, copper, and vanadium, are often correlated with antibiotic resistance. Naturally occurring resistance also stems from interactions between microbes in the environment. Recent research highlights the need to understand patterns of antibiotic resistance in the environment, as well as in clinical se...
We used published data of individuals moving among habitat patches to answer questions pertaining... more We used published data of individuals moving among habitat patches to answer questions pertaining to frequency of interpatch movements and subsequent effects on population dynamics. A review of 415 published articles produced data for 89 species-system combinations where movements were recorded in sufficient detail to include in our analysis. The percentage of individuals in a population that moved among habitat patches ranged from 0.00 to 93.00%, with a mean of 16.84%. Scaling this statistic by generation time yielded a mean movement rate of 15.45 Ϯ 3.27% per generation. The relatively low movement rates suggest that subpopulations, except those of effects of interpatch movement. Of these, thirty-three studies yielded population effects on 34 individual species in 45 species-systems. They reported movement having a positive effect 28 times, a negative effect twice and a neutral effect 14 times. Despite its importance, relatively few studies document rates of interpatch movement and far fewer determine population level consequences of these movements. This deficiency limits our ability to understand the dynamics of spatially structured populations and apply that knowledge to conservation efforts.
Gary W. Barrett John D. Peles Institute of Ecology Savannah River Ecology Laboratory The Universi... more Gary W. Barrett John D. Peles Institute of Ecology Savannah River Ecology Laboratory The University of Georgia The University of Georgia Athens, GA 30602 Aiken, SC 29802 USA USA Cover illustration: Photograph of the Ecology Research Center, Miami University, Oxford, Ohio, ...
One of the most popular approaches for maintaining populations and conserving biodiversity in fra... more One of the most popular approaches for maintaining populations and conserving biodiversity in fragmented landscapes is to retain or create corridors that connect otherwise isolated habitat patches. Working in large-scale, experimental landscapes in which open-habitat patches ...
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Papers by David Bowne