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Bobby Habig - One of the best experts on this subject based on the ideXlab platform.
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multi scale predictors of parasite risk in wild male savanna baboons papio cynocephalus
Behavioral Ecology and Sociobiology, 2019Co-Authors: Bobby Habig, David A W A M Jansen, Mercy Y Akinyi, Laurence R Gesquiere, Susan C Alberts, Elizabeth A ArchieAbstract:Several factors are thought to shape male parasite risk in polygynous and polygynandrous mammals, including male-male competition, investment in potentially immunosuppressive hormones, and dispersal. Parasitism is also driven by processes occurring at larger scales, including host social groups and populations. To date, studies that test parasite-related costs of male behavior at all three scales—individual hosts, social groups, and the host population—remain rare. To fill this gap, we investigated multi-scale predictors of helminth parasitism in 97 male savanna baboons (Papio cynocephalus) living in the Amboseli ecosystem in Kenya over a 5-year span. Controlling for multi-scale processes, we found that many of the classic indicators of male mating effort—high dominance rank, testosterone, and glucocorticoids—did not predict helminth infection risk. However, we identified two parasite-related costs associated with male behavior: (i) socially connected males exhibited higher Trichuris trichiura egg counts and greater parasite species richness than socially isolated males and (ii) males with stable group residency exhibited higher parasite species richness than males who frequently dispersed to new social groups. At the population level, males harbored more parasites following periods of drought than rainfall. Lastly, parasites exhibited Positive Covariance suggesting that infection risk increases if a host already harbors one or more parasite taxa. These results indicate that multi-scale processes are important in driving male parasite risk and that some aspects of male behavior are costly. Together, our results provide an unusually holistic perspective on the drivers of parasite risk in the context of male behaviors and life histories. Infection by gastrointestinal helminths can have major consequences for host fitness, especially in the context of male mating effort. Multi-scale processes—from the host to its social group and population—are important for understanding key drivers of parasitism. We leveraged long-term data from one of the longest running behavioral ecology studies of a wild primate population in the world, the well-studied Amboseli baboon population in Kenya. We found that traditional indicators of male mating effort (attaining high dominance rank, high testosterone and glucocorticoids) did not predict parasitism. However, male social connectedness to females, competitive group demography, and harsh weather were all associated with higher parasitism. Because socially connected males faced the highest parasite risk, males may face a tradeoff between male-female relationships and parasitism. Our results show how processes at multiple scales contribute to variation in male parasite risk.
Elizabeth A Archie - One of the best experts on this subject based on the ideXlab platform.
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multi scale predictors of parasite risk in wild male savanna baboons papio cynocephalus
Behavioral Ecology and Sociobiology, 2019Co-Authors: Bobby Habig, David A W A M Jansen, Mercy Y Akinyi, Laurence R Gesquiere, Susan C Alberts, Elizabeth A ArchieAbstract:Several factors are thought to shape male parasite risk in polygynous and polygynandrous mammals, including male-male competition, investment in potentially immunosuppressive hormones, and dispersal. Parasitism is also driven by processes occurring at larger scales, including host social groups and populations. To date, studies that test parasite-related costs of male behavior at all three scales—individual hosts, social groups, and the host population—remain rare. To fill this gap, we investigated multi-scale predictors of helminth parasitism in 97 male savanna baboons (Papio cynocephalus) living in the Amboseli ecosystem in Kenya over a 5-year span. Controlling for multi-scale processes, we found that many of the classic indicators of male mating effort—high dominance rank, testosterone, and glucocorticoids—did not predict helminth infection risk. However, we identified two parasite-related costs associated with male behavior: (i) socially connected males exhibited higher Trichuris trichiura egg counts and greater parasite species richness than socially isolated males and (ii) males with stable group residency exhibited higher parasite species richness than males who frequently dispersed to new social groups. At the population level, males harbored more parasites following periods of drought than rainfall. Lastly, parasites exhibited Positive Covariance suggesting that infection risk increases if a host already harbors one or more parasite taxa. These results indicate that multi-scale processes are important in driving male parasite risk and that some aspects of male behavior are costly. Together, our results provide an unusually holistic perspective on the drivers of parasite risk in the context of male behaviors and life histories. Infection by gastrointestinal helminths can have major consequences for host fitness, especially in the context of male mating effort. Multi-scale processes—from the host to its social group and population—are important for understanding key drivers of parasitism. We leveraged long-term data from one of the longest running behavioral ecology studies of a wild primate population in the world, the well-studied Amboseli baboon population in Kenya. We found that traditional indicators of male mating effort (attaining high dominance rank, high testosterone and glucocorticoids) did not predict parasitism. However, male social connectedness to females, competitive group demography, and harsh weather were all associated with higher parasitism. Because socially connected males faced the highest parasite risk, males may face a tradeoff between male-female relationships and parasitism. Our results show how processes at multiple scales contribute to variation in male parasite risk.
Arthur A. Small - One of the best experts on this subject based on the ideXlab platform.
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agricultural biotechnology s complementary intellectual assets
The Review of Economics and Statistics, 2003Co-Authors: Gregory D. Graff, Gordon C Rausser, Arthur A. SmallAbstract:We formulate and test a hypothesis for the dramatic restructur- ing that the plant breeding and seed industry has recently undergone: the reorganization can be explained in part by the desire to exploit comple- mentarities between intellectual assets needed to create genetically mod- ified organisms. This hypothesis is tested using data on agricultural biotechnology patents, notices for field tests of genetically modified organisms, and firm characteristics. The presence of complementarities is identified with a Positive Covariance in the unexplained variation of asset holdings. Results indicate that coordination of complementary assets has increased under the consolidation of the industry. NE of the central problems in the economics of inno- vation concerns how industries change as they absorb fundamental research breakthroughs. Rarely has change been more pronounced than in agriculture following the introduction of recombinant DNA technology and affiliated techniques of genetic engineering. By offering breeders the ability to alter plant traits by directly manipulating se- quences of genetic code, tools of agricultural biotechnology change the possibilities for crop improvement profoundly. The new techniques enhance the speed and precision of agricultural research and development (R&D), while ex- panding the space of potential new products. Seed firms now offer farmers crop varieties embodying new ap- proaches for controlling pests, managing physical stresses on plants, increasing crop yields, and growing differenti- ated, quality-enhanced crops. Concurrent with these technical changes in the R&D process, the agricultural inputs industry has over the past two decades witnessed a comprehensive restructuring. Sev- eral large chemical firms, including Monsanto, Dow, and DuPont, moved aggressively into plant biotechnology, mak- ing huge investments in the life sciences. As newly minted "agronomic systems" companies, these firms acquired all of the large, national seed firms in North America, including Pioneer, DeKalb, Asgrow, Garst, and others. Meanwhile, the research-intensive agricultural biotechnology sector, from its appearance in the 1980s as a large set of small startup firms, had by the end of the 1990s already reached a second stage, with most of the startups either folded or acquired by the new agronomic systems giants. The industry's consoli- dation was surprising not only for its rapid pace and com- prehensive scope, but also for the extremely high valuations at which some firms were acquired. In 1997, for example, Monsanto acquired Holdens' Foundation Seeds of Wil- liamsburg, Iowa, together with two marketing subsidiaries, for $1.02 billion—25 times the annual sales of the mature, privately held firm whose revenues derived entirely from the breeding and distribution of corn seed. The emergent industry structure—with a relatively small number of tightly woven alliances, each organized around a major life-sciences firm, each vertically integrated from basic R&D through to marketing—stands in contrast to the more diffuse structure of twenty years ago. This structure is likewise noteworthy when one considers trends in other research-intensive fields. The pharmaceutical biotechnology industry, for example, maintains a large number of free- standing firms specializing in R&D and earning revenues through various licensing agreements (Majewski, 1998). Hall and Ziedonis (2001) observe that the U.S. semiconduc-
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Agricultural biotechnology's complementary intellectual assets
Review of Economics and Statistics, 2003Co-Authors: Gregory D. Graff, Gordon C Rausser, Arthur A. SmallAbstract:We formulate and test a hypothesis for the dramatic restructuring that the plant breeding and seed industry has recently undergone: the reorganization can be explained in part by the desire to exploit complementarities between intellectual assets needed to create genetically modified organisms. This hypothesis is tested using data on agricultural biotechnology patents, notices for field tests of genetically modified organisms, and firm characteristics. The presence of complementarities is identified with a Positive Covariance in the unexplained variation of asset holdings. Results indicate that coordination of complementary assets have increased under the consolidation of the industry.
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agricultural biotechnology s complementary intellectual assets
Research Papers in Economics, 2001Co-Authors: Gregory D. Graff, Gordon C Rausser, Arthur A. SmallAbstract:We formulate and test a hypothesis for the dramatic restructuring that the plant breeding and seed industry has recently undergone: the reorganization can be explained in part by the desire to exploit complementarities between intellectual assets needed to create genetically modified organisms. This hypothesis is tested using data on agricultural biotechnology patents, notices for field tests of genetically modified organisms, and firm characteristics. The presence of complementarities is identified with a Positive Covariance in the unexplained variation of asset holdings. Results indicate that coordination of complementary assets has increased under the consolidation of the industry. © 2003 President and Fellows of Harvard College and the Massachusetts Institute of Technology. (This abstract was borrowed from another version of this item.)
Hans Bengtsson - One of the best experts on this subject based on the ideXlab platform.
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The importance of wildlife in the ecology and epidemiology of the TBE virus in Sweden: incidence of human TBE correlates with abundance of deer and hares
Parasites & Vectors, 2018Co-Authors: Thomas G. T. Jaenson, Erik H. Petersson, David G. E. Jaenson, Jonas Kindberg, John H.-o. Pettersson, Marika Hjertqvist, Jolyon M. Medlock, Hans BengtssonAbstract:Background Tick-borne encephalitis (TBE) is one tick-transmitted disease where the human incidence has increased in some European regions during the last two decades. We aim to find the most important factors causing the increasing incidence of human TBE in Sweden. Based on a review of published data we presume that certain temperature-related variables and the population densities of transmission hosts, i.e. small mammals, and of primary tick maintenance hosts, i.e. cervids and lagomorphs, of the TBE virus vector Ixodes ricinus , are among the potentially most important factors affecting the TBE incidence. Therefore, we compare hunting data of the major tick maintenance hosts and two of their important predators, and four climatic variables with the annual numbers of human cases of neuroinvasive TBE. Data for six Swedish regions where human TBE incidence is high or has recently increased are examined by a time-series analysis. Results from the six regions are combined using a meta-analytical method. Results With a one-year time lag, the roe deer ( Capreolus capreolus ), red deer ( Cervus elaphus ), mountain hare ( Lepus timidus ) and European hare ( Lepus europaeus ) showed Positive Covariance; the Eurasian elk (moose, Alces alces ) and fallow deer ( Dama dama ) negative Covariance; whereas the wild boar ( Sus scrofa ), lynx ( Lynx lynx ), red fox ( Vulpes vulpes ) and the four climate parameters showed no significant Covariance with TBE incidence. All game species combined showed Positive Covariance. Conclusions The epidemiology of TBE varies with time and geography and depends on numerous factors, i.a. climate, virus genotypes, and densities of vectors, tick maintenance hosts and transmission hosts. This study suggests that the increased availability of deer to I. ricinus over large areas of potential tick habitats in southern Sweden increased the density and range of I. ricinus and created new TBEV foci, which resulted in increased incidence of human TBE. New foci may be established by TBE virus-infected birds, or by birds or migrating mammals infested with TBEV-infected ticks. Generally, persistence of TBE virus foci appears to require presence of transmission-competent small mammals, especially mice ( Apodemus spp.) or bank voles ( Myodes glareolus ) .
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the importance of wildlife in the ecology and epidemiology of the tbe virus in sweden incidence of human tbe correlates with abundance of deer and hares
Parasites & Vectors, 2018Co-Authors: Thomas G. T. Jaenson, David G. E. Jaenson, Jonas Kindberg, John H.-o. Pettersson, Marika Hjertqvist, Jolyon M. Medlock, Erik Petersson, Hans BengtssonAbstract:Tick-borne encephalitis (TBE) is one tick-transmitted disease where the human incidence has increased in some European regions during the last two decades. We aim to find the most important factors causing the increasing incidence of human TBE in Sweden. Based on a review of published data we presume that certain temperature-related variables and the population densities of transmission hosts, i.e. small mammals, and of primary tick maintenance hosts, i.e. cervids and lagomorphs, of the TBE virus vector Ixodes ricinus, are among the potentially most important factors affecting the TBE incidence. Therefore, we compare hunting data of the major tick maintenance hosts and two of their important predators, and four climatic variables with the annual numbers of human cases of neuroinvasive TBE. Data for six Swedish regions where human TBE incidence is high or has recently increased are examined by a time-series analysis. Results from the six regions are combined using a meta-analytical method. With a one-year time lag, the roe deer (Capreolus capreolus), red deer (Cervus elaphus), mountain hare (Lepus timidus) and European hare (Lepus europaeus) showed Positive Covariance; the Eurasian elk (moose, Alces alces) and fallow deer (Dama dama) negative Covariance; whereas the wild boar (Sus scrofa), lynx (Lynx lynx), red fox (Vulpes vulpes) and the four climate parameters showed no significant Covariance with TBE incidence. All game species combined showed Positive Covariance. The epidemiology of TBE varies with time and geography and depends on numerous factors, i.a. climate, virus genotypes, and densities of vectors, tick maintenance hosts and transmission hosts. This study suggests that the increased availability of deer to I. ricinus over large areas of potential tick habitats in southern Sweden increased the density and range of I. ricinus and created new TBEV foci, which resulted in increased incidence of human TBE. New foci may be established by TBE virus-infected birds, or by birds or migrating mammals infested with TBEV-infected ticks. Generally, persistence of TBE virus foci appears to require presence of transmission-competent small mammals, especially mice (Apodemus spp.) or bank voles (Myodes glareolus).
Jolyon M. Medlock - One of the best experts on this subject based on the ideXlab platform.
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The importance of wildlife in the ecology and epidemiology of the TBE virus in Sweden: incidence of human TBE correlates with abundance of deer and hares
Parasites & Vectors, 2018Co-Authors: Thomas G. T. Jaenson, Erik H. Petersson, David G. E. Jaenson, Jonas Kindberg, John H.-o. Pettersson, Marika Hjertqvist, Jolyon M. Medlock, Hans BengtssonAbstract:Background Tick-borne encephalitis (TBE) is one tick-transmitted disease where the human incidence has increased in some European regions during the last two decades. We aim to find the most important factors causing the increasing incidence of human TBE in Sweden. Based on a review of published data we presume that certain temperature-related variables and the population densities of transmission hosts, i.e. small mammals, and of primary tick maintenance hosts, i.e. cervids and lagomorphs, of the TBE virus vector Ixodes ricinus , are among the potentially most important factors affecting the TBE incidence. Therefore, we compare hunting data of the major tick maintenance hosts and two of their important predators, and four climatic variables with the annual numbers of human cases of neuroinvasive TBE. Data for six Swedish regions where human TBE incidence is high or has recently increased are examined by a time-series analysis. Results from the six regions are combined using a meta-analytical method. Results With a one-year time lag, the roe deer ( Capreolus capreolus ), red deer ( Cervus elaphus ), mountain hare ( Lepus timidus ) and European hare ( Lepus europaeus ) showed Positive Covariance; the Eurasian elk (moose, Alces alces ) and fallow deer ( Dama dama ) negative Covariance; whereas the wild boar ( Sus scrofa ), lynx ( Lynx lynx ), red fox ( Vulpes vulpes ) and the four climate parameters showed no significant Covariance with TBE incidence. All game species combined showed Positive Covariance. Conclusions The epidemiology of TBE varies with time and geography and depends on numerous factors, i.a. climate, virus genotypes, and densities of vectors, tick maintenance hosts and transmission hosts. This study suggests that the increased availability of deer to I. ricinus over large areas of potential tick habitats in southern Sweden increased the density and range of I. ricinus and created new TBEV foci, which resulted in increased incidence of human TBE. New foci may be established by TBE virus-infected birds, or by birds or migrating mammals infested with TBEV-infected ticks. Generally, persistence of TBE virus foci appears to require presence of transmission-competent small mammals, especially mice ( Apodemus spp.) or bank voles ( Myodes glareolus ) .
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the importance of wildlife in the ecology and epidemiology of the tbe virus in sweden incidence of human tbe correlates with abundance of deer and hares
Parasites & Vectors, 2018Co-Authors: Thomas G. T. Jaenson, David G. E. Jaenson, Jonas Kindberg, John H.-o. Pettersson, Marika Hjertqvist, Jolyon M. Medlock, Erik Petersson, Hans BengtssonAbstract:Tick-borne encephalitis (TBE) is one tick-transmitted disease where the human incidence has increased in some European regions during the last two decades. We aim to find the most important factors causing the increasing incidence of human TBE in Sweden. Based on a review of published data we presume that certain temperature-related variables and the population densities of transmission hosts, i.e. small mammals, and of primary tick maintenance hosts, i.e. cervids and lagomorphs, of the TBE virus vector Ixodes ricinus, are among the potentially most important factors affecting the TBE incidence. Therefore, we compare hunting data of the major tick maintenance hosts and two of their important predators, and four climatic variables with the annual numbers of human cases of neuroinvasive TBE. Data for six Swedish regions where human TBE incidence is high or has recently increased are examined by a time-series analysis. Results from the six regions are combined using a meta-analytical method. With a one-year time lag, the roe deer (Capreolus capreolus), red deer (Cervus elaphus), mountain hare (Lepus timidus) and European hare (Lepus europaeus) showed Positive Covariance; the Eurasian elk (moose, Alces alces) and fallow deer (Dama dama) negative Covariance; whereas the wild boar (Sus scrofa), lynx (Lynx lynx), red fox (Vulpes vulpes) and the four climate parameters showed no significant Covariance with TBE incidence. All game species combined showed Positive Covariance. The epidemiology of TBE varies with time and geography and depends on numerous factors, i.a. climate, virus genotypes, and densities of vectors, tick maintenance hosts and transmission hosts. This study suggests that the increased availability of deer to I. ricinus over large areas of potential tick habitats in southern Sweden increased the density and range of I. ricinus and created new TBEV foci, which resulted in increased incidence of human TBE. New foci may be established by TBE virus-infected birds, or by birds or migrating mammals infested with TBEV-infected ticks. Generally, persistence of TBE virus foci appears to require presence of transmission-competent small mammals, especially mice (Apodemus spp.) or bank voles (Myodes glareolus).