Scott Carroll | University of California, Davis (original) (raw)
Papers by Scott Carroll
Ongoing adaptation in native populations to anthropogenic change both facilitates and challenges ... more Ongoing adaptation in native populations to anthropogenic change both facilitates and challenges ecologically appropriate and sustainable management. Human disturbance promotes adaptive responses at the genomic, individual and population levels. Traits vary widely in whether adaptation occurs through plasticity or evolution, and these modes inter-act within and among traits. For example, plasticity in one trait may be adaptive because it permits homeostasis and lessens the intensity of selection in another. Both opportunity and catastrophe generate adaptive responses. Recently evolved adaptations characterize the responses of many native species to biotic invasions. Several well-known examples involve native phytophagous insects colonizing introduced plants. For example, our studies of North American and Australian soapberry bugs on nonindigenous plants demonstrate both diversifying and homogenizing contemporary evolution. Modes of adaptation differ among traits and populations and ...
Page 195. 12 Managing Phenotypic Variability with Genetic and Environmental Heterogeneity: Adapta... more Page 195. 12 Managing Phenotypic Variability with Genetic and Environmental Heterogeneity: Adaptation as a First Principle of Conservation Practice SCOTT P. CARROLL JASON V. WATTERS Seasons pass, succession proceeds, landscapes riseand erode. ...
Evolutionary Ecology, Oct 31, 1998
With reciprocal rearing experiments, we tested the hypothesis that adaptive dierences in host-use... more With reciprocal rearing experiments, we tested the hypothesis that adaptive dierences in host-use traits among soapberry bug populations have a genetic basis. These experiments were conducted with two host races from Florida, an`ancestral-type' one on a native host plant species and a`derived' one on a recently introduced plant species (colonized mainly post-1950), on whose seed crops this insect depends for growth and reproduction. Compared to the native host species, the introduced host produces larger seed crops over a much briefer annual period. Its seeds are also signi®cantly higher in lipids and lower in nitrogen. The bug populations exhibit greater juvenile survivorship on their`home' hosts; that is, the derived population survives better on seeds of the introduced host than does its ancestral-type counterpart, and vice versa. Regardless of the rearing host, populations from the introduced host lay much smaller eggs, and fecundity measures show a more complex pattern than does survivorship: the ancestral-type population produces eggs at the same rate on each host, while the derived population is less fecund on the native host and exhibits enhanced fecundity on the introduced host. These results indicate that the population dierences are evolved rather than hostinduced. They appear to be adaptive responses to host dierences in the spatial and temporal distribution of seed availability and nutritional quality, and show that increased performance on the alien host has evolved with surprising speed and magnitude, with concomitant reductions in performance on the original host.
Journal of Insect Behavior, 1990
... 5. The influence of breeding systems and mating systems on conservation genetics and conserva... more ... 5. The influence of breeding systems and mating systems on conservation genetics and conservation decisions Michele R. Dudash a Courtney J. Murren. ... 11. Evolutionary dynamics of adaptation to environmental stress George W. Gilchrist and Donna G. Folk. 12. ...
Page 92. Chapter 4 Conservation, behavior, and 99% of the world's biodiv... more Page 92. Chapter 4 Conservation, behavior, and 99% of the world's biodiversity: Is our ignorance really bliss? HUGH DINGLE, SCOTT P. CARROLL, AND JENELLA E. LOYE If all vertebrates went extinct, there would for all practical ...
Annals of the Entomological Society of America, 1994
Annals of the Entomological Society of America, 1988
The Quarterly Review of Biology, 1997
Molecular Ecology, 2008
Ongoing adaptation in native populations to anthropogenic change both facilitates and challenges ... more Ongoing adaptation in native populations to anthropogenic change both facilitates and challenges ecologically appropriate and sustainable management. Human disturbance promotes adaptive responses at the genomic, individual and population levels. Traits vary widely in whether adaptation occurs through plasticity or evolution, and these modes interact within and among traits. For example, plasticity in one trait may be adaptive because it permits homeostasis and lessens the intensity of selection in another.
Molecular Ecology, 2013
Contemporary adaptation of plant feeding insects to introduced hosts provides clear cases of ecol... more Contemporary adaptation of plant feeding insects to introduced hosts provides clear cases of ecologically based population divergence. In most cases the mechanisms permitting rapid differentiation are not well known. Here we study morphological and genetic variation associated with recent shifts by the Australian soapberry bug Leptocoris tagalicus onto two naturalized Neotropical balloon vines, Cardiospermum halicacabum and C. grandiflorum that differ in time since introduction. Our results show that these vines have much larger fruits than the native hosts (Whitewood tree -Atalaya hemiglauca- and Woolly Rambutan -Alectryon tomentosus-) and that bugs living on them have evolved significantly longer beaks and new allometries. Genetic analyses of mitochondrial haplotypes and amplified fragment length polymorphic (AFLP) markers indicate that the lineage of bugs on the annual vine C. halicacabum, the older introduction, is intermediate between the two subspecies of L. tagalicus found on native hosts. Moreover, where the annual vine and Whitewood tree co-occur, the morphology and genomic composition of the bugs are similar to those occurring in allopatry. These results show that hybridization provided the genetic elements underlying the strongly differentiated 'Halicacabum bugs'. In contrast, the bugs feeding on the recently introduced perennial balloon vine (C. grandiflorum) showed no evidence of admixture, and are genetically indistinguishable from the nearby populations on a native host.
Journal of Medical Entomology, 2008
Here I report the Þrst Þndings of consistently high, long-duration efÞcacy of IR3535 (ethyl butyl... more Here I report the Þrst Þndings of consistently high, long-duration efÞcacy of IR3535 (ethyl butyl acetyl aminopropionate) formulations in the United States. I tested novel, controlledrelease formulations of IR3535, at 10% in lotion and at 20% in pump spray and aerosol, against mosquitoes in the Þeld and blacklegged ticks in the laboratory. These were also the Þrst studies to be conducted under the authority of the U.S. Environmental Protection AgencyÕs Human Studies Rule of 2006, and the protocols underwent science and ethics reviews by Þve entities. IR3535 is better known in Europe than in North America, having been marketed in the United States only more recently, and there are comparatively few publications on its efÞcacy. I began with pretrial studies of dosing behavior to compute formula-speciÞc mean dosing rates for the subsequent efÞcacy trials. Dosing rates were lower than the 1 ml/600 cm rate commonly used to quantify efÞcacy. Complete protection times ranged from 7.1 to 10.3 h for mosquitoes and from 9.1 to 12.2 h for blacklegged ticks. Long protection duration resulted in many cases being truncated by darkness or eventual subject withdrawal, which suggests that actual protection times were probably greater.
Evolution, 1992
Page 1. Host Race Radiation in the Soapberry Bug: Natural History with the History Scott P. Carro... more Page 1. Host Race Radiation in the Soapberry Bug: Natural History with the History Scott P. Carroll; Christin Boyd Evolution, Vol. 46, No. 4. (Aug., 1992), pp. 1053-1069. Stable URL: http://links.jstor.org/sici?sici=0014-3820%28199208 ...
Evolution, 1997
In this study we used reciprocal rearing experiments to test the hypothesis that there is a genet... more In this study we used reciprocal rearing experiments to test the hypothesis that there is a genetic basis for the adaptive differences in host-use traits among host-associated soapberry bug populations (described in Carroll and Boyd 1992). These experiments were conducted on two host races from Florida, in which differences in beak length and development were found between natural populations on a native host plant species and those on a recently introduced plant species (colonized mainly post-1950). Performance was generally superior on the host species from which each lab population originated (i.e., on the "Home" host species): in analysis of variance, there was significant population-by-host interaction for size, development time, and growth rate. These results indicate that the population differences in nature are evolved rather than host induced. Increased performance on the introduced host was accompanied by reduced performance on the native host, a pattern that could theoretically promote further differentiation between the host races.
Birdparasite interactions: Ecology, evolution and …, 1991
ABSTRACT Ectoparasite density is correlated with Hirundo pyrrhonota colony site selection, shorte... more ABSTRACT Ectoparasite density is correlated with Hirundo pyrrhonota colony site selection, shortened nesting period, and early migration. Cliff swallow nests contained four species of ectoparasites: the flea Ceratophyllus celsus (Siphonaptera: Ceratophyllidae); ticks Ixodes baergi (Acari: Ixodidae) and Ornithodoros concannensis (Acari: Argasidae); and the cliff swallow bug Oeciacus vicarius (Hemiptera: Cimicidae). Swallow bugs were by far the most numerous and consistently present of the ectoparasites. Blood-sucking, nest-dwelling arthropods have strongly influenced the evolution of nesting behaviour in the colonial cliff swallow. -from Authors
Ongoing adaptation in native populations to anthropogenic change both facilitates and challenges ... more Ongoing adaptation in native populations to anthropogenic change both facilitates and challenges ecologically appropriate and sustainable management. Human disturbance promotes adaptive responses at the genomic, individual and population levels. Traits vary widely in whether adaptation occurs through plasticity or evolution, and these modes inter-act within and among traits. For example, plasticity in one trait may be adaptive because it permits homeostasis and lessens the intensity of selection in another. Both opportunity and catastrophe generate adaptive responses. Recently evolved adaptations characterize the responses of many native species to biotic invasions. Several well-known examples involve native phytophagous insects colonizing introduced plants. For example, our studies of North American and Australian soapberry bugs on nonindigenous plants demonstrate both diversifying and homogenizing contemporary evolution. Modes of adaptation differ among traits and populations and ...
Page 195. 12 Managing Phenotypic Variability with Genetic and Environmental Heterogeneity: Adapta... more Page 195. 12 Managing Phenotypic Variability with Genetic and Environmental Heterogeneity: Adaptation as a First Principle of Conservation Practice SCOTT P. CARROLL JASON V. WATTERS Seasons pass, succession proceeds, landscapes riseand erode. ...
Evolutionary Ecology, Oct 31, 1998
With reciprocal rearing experiments, we tested the hypothesis that adaptive dierences in host-use... more With reciprocal rearing experiments, we tested the hypothesis that adaptive dierences in host-use traits among soapberry bug populations have a genetic basis. These experiments were conducted with two host races from Florida, an`ancestral-type' one on a native host plant species and a`derived' one on a recently introduced plant species (colonized mainly post-1950), on whose seed crops this insect depends for growth and reproduction. Compared to the native host species, the introduced host produces larger seed crops over a much briefer annual period. Its seeds are also signi®cantly higher in lipids and lower in nitrogen. The bug populations exhibit greater juvenile survivorship on their`home' hosts; that is, the derived population survives better on seeds of the introduced host than does its ancestral-type counterpart, and vice versa. Regardless of the rearing host, populations from the introduced host lay much smaller eggs, and fecundity measures show a more complex pattern than does survivorship: the ancestral-type population produces eggs at the same rate on each host, while the derived population is less fecund on the native host and exhibits enhanced fecundity on the introduced host. These results indicate that the population dierences are evolved rather than hostinduced. They appear to be adaptive responses to host dierences in the spatial and temporal distribution of seed availability and nutritional quality, and show that increased performance on the alien host has evolved with surprising speed and magnitude, with concomitant reductions in performance on the original host.
Journal of Insect Behavior, 1990
... 5. The influence of breeding systems and mating systems on conservation genetics and conserva... more ... 5. The influence of breeding systems and mating systems on conservation genetics and conservation decisions Michele R. Dudash a Courtney J. Murren. ... 11. Evolutionary dynamics of adaptation to environmental stress George W. Gilchrist and Donna G. Folk. 12. ...
Page 92. Chapter 4 Conservation, behavior, and 99% of the world's biodiv... more Page 92. Chapter 4 Conservation, behavior, and 99% of the world's biodiversity: Is our ignorance really bliss? HUGH DINGLE, SCOTT P. CARROLL, AND JENELLA E. LOYE If all vertebrates went extinct, there would for all practical ...
Annals of the Entomological Society of America, 1994
Annals of the Entomological Society of America, 1988
The Quarterly Review of Biology, 1997
Molecular Ecology, 2008
Ongoing adaptation in native populations to anthropogenic change both facilitates and challenges ... more Ongoing adaptation in native populations to anthropogenic change both facilitates and challenges ecologically appropriate and sustainable management. Human disturbance promotes adaptive responses at the genomic, individual and population levels. Traits vary widely in whether adaptation occurs through plasticity or evolution, and these modes interact within and among traits. For example, plasticity in one trait may be adaptive because it permits homeostasis and lessens the intensity of selection in another.
Molecular Ecology, 2013
Contemporary adaptation of plant feeding insects to introduced hosts provides clear cases of ecol... more Contemporary adaptation of plant feeding insects to introduced hosts provides clear cases of ecologically based population divergence. In most cases the mechanisms permitting rapid differentiation are not well known. Here we study morphological and genetic variation associated with recent shifts by the Australian soapberry bug Leptocoris tagalicus onto two naturalized Neotropical balloon vines, Cardiospermum halicacabum and C. grandiflorum that differ in time since introduction. Our results show that these vines have much larger fruits than the native hosts (Whitewood tree -Atalaya hemiglauca- and Woolly Rambutan -Alectryon tomentosus-) and that bugs living on them have evolved significantly longer beaks and new allometries. Genetic analyses of mitochondrial haplotypes and amplified fragment length polymorphic (AFLP) markers indicate that the lineage of bugs on the annual vine C. halicacabum, the older introduction, is intermediate between the two subspecies of L. tagalicus found on native hosts. Moreover, where the annual vine and Whitewood tree co-occur, the morphology and genomic composition of the bugs are similar to those occurring in allopatry. These results show that hybridization provided the genetic elements underlying the strongly differentiated 'Halicacabum bugs'. In contrast, the bugs feeding on the recently introduced perennial balloon vine (C. grandiflorum) showed no evidence of admixture, and are genetically indistinguishable from the nearby populations on a native host.
Journal of Medical Entomology, 2008
Here I report the Þrst Þndings of consistently high, long-duration efÞcacy of IR3535 (ethyl butyl... more Here I report the Þrst Þndings of consistently high, long-duration efÞcacy of IR3535 (ethyl butyl acetyl aminopropionate) formulations in the United States. I tested novel, controlledrelease formulations of IR3535, at 10% in lotion and at 20% in pump spray and aerosol, against mosquitoes in the Þeld and blacklegged ticks in the laboratory. These were also the Þrst studies to be conducted under the authority of the U.S. Environmental Protection AgencyÕs Human Studies Rule of 2006, and the protocols underwent science and ethics reviews by Þve entities. IR3535 is better known in Europe than in North America, having been marketed in the United States only more recently, and there are comparatively few publications on its efÞcacy. I began with pretrial studies of dosing behavior to compute formula-speciÞc mean dosing rates for the subsequent efÞcacy trials. Dosing rates were lower than the 1 ml/600 cm rate commonly used to quantify efÞcacy. Complete protection times ranged from 7.1 to 10.3 h for mosquitoes and from 9.1 to 12.2 h for blacklegged ticks. Long protection duration resulted in many cases being truncated by darkness or eventual subject withdrawal, which suggests that actual protection times were probably greater.
Evolution, 1992
Page 1. Host Race Radiation in the Soapberry Bug: Natural History with the History Scott P. Carro... more Page 1. Host Race Radiation in the Soapberry Bug: Natural History with the History Scott P. Carroll; Christin Boyd Evolution, Vol. 46, No. 4. (Aug., 1992), pp. 1053-1069. Stable URL: http://links.jstor.org/sici?sici=0014-3820%28199208 ...
Evolution, 1997
In this study we used reciprocal rearing experiments to test the hypothesis that there is a genet... more In this study we used reciprocal rearing experiments to test the hypothesis that there is a genetic basis for the adaptive differences in host-use traits among host-associated soapberry bug populations (described in Carroll and Boyd 1992). These experiments were conducted on two host races from Florida, in which differences in beak length and development were found between natural populations on a native host plant species and those on a recently introduced plant species (colonized mainly post-1950). Performance was generally superior on the host species from which each lab population originated (i.e., on the "Home" host species): in analysis of variance, there was significant population-by-host interaction for size, development time, and growth rate. These results indicate that the population differences in nature are evolved rather than host induced. Increased performance on the introduced host was accompanied by reduced performance on the native host, a pattern that could theoretically promote further differentiation between the host races.
Birdparasite interactions: Ecology, evolution and …, 1991
ABSTRACT Ectoparasite density is correlated with Hirundo pyrrhonota colony site selection, shorte... more ABSTRACT Ectoparasite density is correlated with Hirundo pyrrhonota colony site selection, shortened nesting period, and early migration. Cliff swallow nests contained four species of ectoparasites: the flea Ceratophyllus celsus (Siphonaptera: Ceratophyllidae); ticks Ixodes baergi (Acari: Ixodidae) and Ornithodoros concannensis (Acari: Argasidae); and the cliff swallow bug Oeciacus vicarius (Hemiptera: Cimicidae). Swallow bugs were by far the most numerous and consistently present of the ectoparasites. Blood-sucking, nest-dwelling arthropods have strongly influenced the evolution of nesting behaviour in the colonial cliff swallow. -from Authors