Laura Jones | Cornell University (original) (raw)
Papers by Laura Jones
Journal of Theoretical Biology, 2013
When there is conspicuous underexploitation of a limited resource, it is worth asking, what mecha... more When there is conspicuous underexploitation of a limited resource, it is worth asking, what mechanisms allow presumconsistently low resource use by a parasitoid, Hyposoter horticola (Hymenoptera: Ichneumonidae). This wasp parasitizes the butterfly Melitaea cinxia (Lepidoptera: Nymably valuable resources to be left unused? Evolutionary biologists have generated a wide variety of hypotheses to explain this, ranging from interdemic group selection to selfishly prudent individual restraint. We consider a situation in which, despite high intraspecific competition, individuals leave most of a key resource unexploited. The parasitic wasp that does this finds virtually all host egg clusters in a landscape but parasitizes only about a third of the eggs in each and then leaves a deterrent mark around the cluster. We first test—and reject—a series of system-specific simple constraints that might limit full host exploitation, such as asynchronous maturation of host eggs. We then consider classi...
Intraspecific Competition in the Population of Danaus plexippus (L.) Cornell Univ., Dept. op Biol... more Intraspecific Competition in the Population of Danaus plexippus (L.) Cornell Univ., Dept. op Biological Statistics & Computational Biology Technical Report BU-1615-M Roberto Saenz University of Texas at El Paso Julie Stein New College of Florida Aziz Yakubu Howard University ...
Proceedings of the National Academy of Sciences of the United States of America, Aug 2, 2018
The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conse... more The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and so...
Proceedings of the National Academy of Sciences, 2006
Using rotifer–algal microcosms, we tracked rapid evolution resulting from temporally changing nat... more Using rotifer–algal microcosms, we tracked rapid evolution resulting from temporally changing natural selection in ecological predator–prey dynamics. We previously demonstrated that predator–prey oscillations in rotifer–algal laboratory microcosms are qualitatively altered by the presence of genetic variation within the prey. In that study, changes in algal gene frequencies were inferred from their effects on population dynamics but not observed directly. Here, we document rapid prey evolution in this system by directly observing changes in Chlorella vulgaris genotype frequencies as the abundances of these algae and their consumer, Brachionus calyciflorus , change through time. We isolated a group of algal clones that we could distinguish by using microsatellite-DNA markers, and developed an allele-specific quantitative PCR technique (AsQ-PCR) to quantify the frequencies of pairs of clones in mixed culture. We showed that two of these genotypes exhibited a fitness tradeoff in which ...
Mathematical Biosciences, 2004
When there is conspicuous under-exploitation of a limited resource, it is worth asking what mecha... more When there is conspicuous under-exploitation of a limited resource, it is worth asking what mechanisms allow presumably valuable resources to be left unused? Evolutionary biologists have generated a wide range of hypotheses to explain this, ranging from interdemic group selection to selfishly prudent individual restraint. We consider a situation in which, in spite of high intraspecific competition, individuals leave most of a key resource unexploited. The parasitic wasp that does this finds virtually all host egg clusters in a landscape, but parasitizes only about a third of the eggs in each, and then leaves a deterrent mark around the cluster. We first test, and reject, a series of system-specific simple constraints that might limit full host exploitation, such as asynchronous maturation of host eggs. We then consider classical hypotheses for the evolution of restraint. Prudent predation and bet-hedging fail as explanations because the wasp lives as a large well-mixed population. A...
Journal of Virology, 2008
The death of CD4 + CCR5 + T cells is a hallmark of human immunodeficiency virus (HIV) infection. ... more The death of CD4 + CCR5 + T cells is a hallmark of human immunodeficiency virus (HIV) infection. We studied the plasma levels of cell death mediators and products—tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), Fas ligand, TNF receptor type 2 (TNFR-2), and plasma microparticles—during the earliest stages of infection following HIV type 1 (HIV-1) transmission in plasma samples from U.S. plasma donors. Significant plasma TRAIL level elevations occurred a mean of 7.2 days before the peak of plasma viral load (VL), while TNFR-2, Fas ligand, and microparticle level elevations occurred concurrently with maximum VL. Microparticles had been previously shown to mediate immunosuppressive effects on T cells and macrophages. We found that T-cell apoptotic microparticles also potently suppressed in vitro immunoglobulin G (IgG) and IgA antibody production by memory B cells. Thus, release of TRAIL during the onset of plasma viremia (i.e., the eclipse phase) in HIV-1 transmis...
JAIDS Journal of Acquired Immune Deficiency Syndromes, 2002
The American Naturalist, 2007
Bulletin of the Seismological Society of America
The 28 June 1992 Big Bear earthquake occurred at 15:05:21 GMT and is considered to be an aftersho... more The 28 June 1992 Big Bear earthquake occurred at 15:05:21 GMT and is considered to be an aftershock of the earlier Mw = 7.3 Landers earthquake. From overall aftershock locations and long-period focal studies, rupture is generally assumed to have propagated northeast. No surface rupture was found, however, and the mainshock locations determined from both strong motion and TERRAscope data are mutually consistent and do not lie on the assumed fault plane. Further, directivity analysis of records from the TERRAscope array suggests significant short- and long-period energy propagating northwest along the presumed antithetic fault plane. This observation is supported by significant early aftershocks distributed along both the presumed rupture plane and the antithetic plane to the northwest. An empirical Green's function (eGf) approach using both the Mw = 5.2, 28 June 1992 14:43 GMT foreshock and the Mw = 5.0 17 August 1992 aftershock produces consistent results and suggests that the B...
Background/Question/Methods Increasing numbers of studies show correlations between agricultural ... more Background/Question/Methods Increasing numbers of studies show correlations between agricultural landscape diversity, natural enemy populations, and suppressed pest densities. However, most studies focus on the role of diverse landscapes in suppressing pest populations by conserving natural enemies without considering the role such landscapes may play in directly suppressing herbivorous pests. In this paper, we constructed spatially explicit models to explore the direct effects of agricultural landscape diversity on the population dynamics of herbivorous insects. Characteristics of the landscape, such as the amount of suitable host habitat, its degree of clustering and the crop rotation rate, as well as characteristics of the herbivore such as dispersal behavior and host plant specificity were varied. Results/Conclusions Landscape structure plays a strong role in determining whether herbivore populations become established in a landscape. Landscape diversification is especially effe...
The American Naturalist, 2015
Advances in Ecological Research, 2005
... al., 2002). In our model for that hypothesis, like the Abrams and Matsuda (1997) model, prey ... more ... al., 2002). In our model for that hypothesis, like the Abrams and Matsuda (1997) model, prey are able to evolve defense against predation, but only with a trade-off in their maximum population growth rate. Our model differed ...
Journal of Geophysical Research, 1992
Geophysical Research Letters, 1997
Journal of Theoretical Biology, 2013
When there is conspicuous underexploitation of a limited resource, it is worth asking, what mecha... more When there is conspicuous underexploitation of a limited resource, it is worth asking, what mechanisms allow presumconsistently low resource use by a parasitoid, Hyposoter horticola (Hymenoptera: Ichneumonidae). This wasp parasitizes the butterfly Melitaea cinxia (Lepidoptera: Nymably valuable resources to be left unused? Evolutionary biologists have generated a wide variety of hypotheses to explain this, ranging from interdemic group selection to selfishly prudent individual restraint. We consider a situation in which, despite high intraspecific competition, individuals leave most of a key resource unexploited. The parasitic wasp that does this finds virtually all host egg clusters in a landscape but parasitizes only about a third of the eggs in each and then leaves a deterrent mark around the cluster. We first test—and reject—a series of system-specific simple constraints that might limit full host exploitation, such as asynchronous maturation of host eggs. We then consider classi...
Intraspecific Competition in the Population of Danaus plexippus (L.) Cornell Univ., Dept. op Biol... more Intraspecific Competition in the Population of Danaus plexippus (L.) Cornell Univ., Dept. op Biological Statistics & Computational Biology Technical Report BU-1615-M Roberto Saenz University of Texas at El Paso Julie Stein New College of Florida Aziz Yakubu Howard University ...
Proceedings of the National Academy of Sciences of the United States of America, Aug 2, 2018
The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conse... more The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and so...
Proceedings of the National Academy of Sciences, 2006
Using rotifer–algal microcosms, we tracked rapid evolution resulting from temporally changing nat... more Using rotifer–algal microcosms, we tracked rapid evolution resulting from temporally changing natural selection in ecological predator–prey dynamics. We previously demonstrated that predator–prey oscillations in rotifer–algal laboratory microcosms are qualitatively altered by the presence of genetic variation within the prey. In that study, changes in algal gene frequencies were inferred from their effects on population dynamics but not observed directly. Here, we document rapid prey evolution in this system by directly observing changes in Chlorella vulgaris genotype frequencies as the abundances of these algae and their consumer, Brachionus calyciflorus , change through time. We isolated a group of algal clones that we could distinguish by using microsatellite-DNA markers, and developed an allele-specific quantitative PCR technique (AsQ-PCR) to quantify the frequencies of pairs of clones in mixed culture. We showed that two of these genotypes exhibited a fitness tradeoff in which ...
Mathematical Biosciences, 2004
When there is conspicuous under-exploitation of a limited resource, it is worth asking what mecha... more When there is conspicuous under-exploitation of a limited resource, it is worth asking what mechanisms allow presumably valuable resources to be left unused? Evolutionary biologists have generated a wide range of hypotheses to explain this, ranging from interdemic group selection to selfishly prudent individual restraint. We consider a situation in which, in spite of high intraspecific competition, individuals leave most of a key resource unexploited. The parasitic wasp that does this finds virtually all host egg clusters in a landscape, but parasitizes only about a third of the eggs in each, and then leaves a deterrent mark around the cluster. We first test, and reject, a series of system-specific simple constraints that might limit full host exploitation, such as asynchronous maturation of host eggs. We then consider classical hypotheses for the evolution of restraint. Prudent predation and bet-hedging fail as explanations because the wasp lives as a large well-mixed population. A...
Journal of Virology, 2008
The death of CD4 + CCR5 + T cells is a hallmark of human immunodeficiency virus (HIV) infection. ... more The death of CD4 + CCR5 + T cells is a hallmark of human immunodeficiency virus (HIV) infection. We studied the plasma levels of cell death mediators and products—tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), Fas ligand, TNF receptor type 2 (TNFR-2), and plasma microparticles—during the earliest stages of infection following HIV type 1 (HIV-1) transmission in plasma samples from U.S. plasma donors. Significant plasma TRAIL level elevations occurred a mean of 7.2 days before the peak of plasma viral load (VL), while TNFR-2, Fas ligand, and microparticle level elevations occurred concurrently with maximum VL. Microparticles had been previously shown to mediate immunosuppressive effects on T cells and macrophages. We found that T-cell apoptotic microparticles also potently suppressed in vitro immunoglobulin G (IgG) and IgA antibody production by memory B cells. Thus, release of TRAIL during the onset of plasma viremia (i.e., the eclipse phase) in HIV-1 transmis...
JAIDS Journal of Acquired Immune Deficiency Syndromes, 2002
The American Naturalist, 2007
Bulletin of the Seismological Society of America
The 28 June 1992 Big Bear earthquake occurred at 15:05:21 GMT and is considered to be an aftersho... more The 28 June 1992 Big Bear earthquake occurred at 15:05:21 GMT and is considered to be an aftershock of the earlier Mw = 7.3 Landers earthquake. From overall aftershock locations and long-period focal studies, rupture is generally assumed to have propagated northeast. No surface rupture was found, however, and the mainshock locations determined from both strong motion and TERRAscope data are mutually consistent and do not lie on the assumed fault plane. Further, directivity analysis of records from the TERRAscope array suggests significant short- and long-period energy propagating northwest along the presumed antithetic fault plane. This observation is supported by significant early aftershocks distributed along both the presumed rupture plane and the antithetic plane to the northwest. An empirical Green's function (eGf) approach using both the Mw = 5.2, 28 June 1992 14:43 GMT foreshock and the Mw = 5.0 17 August 1992 aftershock produces consistent results and suggests that the B...
Background/Question/Methods Increasing numbers of studies show correlations between agricultural ... more Background/Question/Methods Increasing numbers of studies show correlations between agricultural landscape diversity, natural enemy populations, and suppressed pest densities. However, most studies focus on the role of diverse landscapes in suppressing pest populations by conserving natural enemies without considering the role such landscapes may play in directly suppressing herbivorous pests. In this paper, we constructed spatially explicit models to explore the direct effects of agricultural landscape diversity on the population dynamics of herbivorous insects. Characteristics of the landscape, such as the amount of suitable host habitat, its degree of clustering and the crop rotation rate, as well as characteristics of the herbivore such as dispersal behavior and host plant specificity were varied. Results/Conclusions Landscape structure plays a strong role in determining whether herbivore populations become established in a landscape. Landscape diversification is especially effe...
The American Naturalist, 2015
Advances in Ecological Research, 2005
... al., 2002). In our model for that hypothesis, like the Abrams and Matsuda (1997) model, prey ... more ... al., 2002). In our model for that hypothesis, like the Abrams and Matsuda (1997) model, prey are able to evolve defense against predation, but only with a trade-off in their maximum population growth rate. Our model differed ...
Journal of Geophysical Research, 1992
Geophysical Research Letters, 1997