Parsnip webworms and host plants at home and abroad: Trophic complexity in a geographic mosaic
May R. Berenbaum, Arthur R. Zangerl
Center for Advanced Study
Carl R. Woese Institute for Genomic Biology
Natural Resources and Environmental Sciences
Due to differences in the structure of communities in which interactions are embedded, the intensity of interactions between species may vary with location; thus, what results from differences in outcomes and in degree of specialization is a geographic mosaic, which provides the raw material for divergent coevolutionary trajectories. Where selection intensity is great, reciprocal responses are likely in so-called "hotspots"; in contrast, where selection pressures are relaxed, reciprocal responses in "coldspots" are far less likely to occur. There are few if any studies examining how a gradient of increasing trophic complexity might influence the probability of phenotype matching and, correspondingly, the " temperature" of the coevolutionary interaction. This study was conducted to compare outcomes of the interaction between wild parsnip (Pastinaca sativa) and parsnip webworm (Depressaria pastinacella) in its indigenous area, Europe, to its area of introduction, the midwestern United States. Specifically, we tested the hypothesis that increasing trophic complexity, represented by alternate host plants or the presence of natural enemies, reduces the selective impact of parsnip webworms and hence diminishes linkage between host plant chemistry and webworms that would be expected in coevolutionary hotspots. This comparison of a two-species interaction in its area of introduction and its area of indigeneity revealed common patterns that are more reflective of interaction temperature than of continental origin. Where webworms are rare, parsnips produce lower levels of xanthotoxin and bergapten in both the midwestern United States and Netherlands populations. However, the most striking result from this intercontinental comparison is that what is a ubiquitous two-species interaction in North America is in fact exceptional in Europe; webworms could more reliably be found infesting H. sphondylium even where P. sativa was available as well. This preference for H. sphondylium exists despite the comparatively high probability of parasitism associated with this host plant and may reflect the overall lower furanocoumarin content of H. sphondylium. The interaction of parsnip webworms and wild parsnips at home and away demonstrates clearly the potential for rapid contemporary evolution of chemical traits upon re-association with a coevolved enemy, a potential evolutionary outcome that should be considered in the design and implementation of future weed biological control programs.
https://doi.org/10.1890/0012-9658(2006)87[3070:PWAHPA]2.0.CO;2
Coevolution
Depressaria pastinacella
Furanocoumarin
Geographic mosaic
Insect-plant interaction
Trophic complexity
10.1890/0012-9658(2006)87[3070:PWAHPA]2.0.CO;2
Dive into the research topics of 'Parsnip webworms and host plants at home and abroad: Trophic complexity in a geographic mosaic'. Together they form a unique fingerprint.
Depressaria pastinacella Agriculture & Biology 100%
host plant Earth & Environmental Sciences 73%
Heracleum Agriculture & Biology 65%
parsnips Agriculture & Biology 64%
mosaic Earth & Environmental Sciences 52%
Pastinaca sativa Agriculture & Biology 45%
host plants Agriculture & Biology 43%
Midwestern United States Agriculture & Biology 35%
Berenbaum, M. R., & Zangerl, A. R. (2006). Parsnip webworms and host plants at home and abroad: Trophic complexity in a geographic mosaic. Ecology, 87(12), 3070-3081. https://doi.org/10.1890/0012-9658(2006)87[3070:PWAHPA]2.0.CO;2
Parsnip webworms and host plants at home and abroad : Trophic complexity in a geographic mosaic. / Berenbaum, May R.; Zangerl, Arthur R.
In: Ecology, Vol. 87, No. 12, 12.2006, p. 3070-3081.
Berenbaum, MR & Zangerl, AR 2006, 'Parsnip webworms and host plants at home and abroad: Trophic complexity in a geographic mosaic', Ecology, vol. 87, no. 12, pp. 3070-3081. https://doi.org/10.1890/0012-9658(2006)87[3070:PWAHPA]2.0.CO;2
Berenbaum MR, Zangerl AR. Parsnip webworms and host plants at home and abroad: Trophic complexity in a geographic mosaic. Ecology. 2006 Dec;87(12):3070-3081. doi: 10.1890/0012-9658(2006)87[3070:PWAHPA]2.0.CO;2
Berenbaum, May R. ; Zangerl, Arthur R. / Parsnip webworms and host plants at home and abroad : Trophic complexity in a geographic mosaic. In: Ecology. 2006 ; Vol. 87, No. 12. pp. 3070-3081.
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title = "Parsnip webworms and host plants at home and abroad: Trophic complexity in a geographic mosaic",
abstract = "Due to differences in the structure of communities in which interactions are embedded, the intensity of interactions between species may vary with location; thus, what results from differences in outcomes and in degree of specialization is a geographic mosaic, which provides the raw material for divergent coevolutionary trajectories. Where selection intensity is great, reciprocal responses are likely in so-called {"}hotspots{"}; in contrast, where selection pressures are relaxed, reciprocal responses in {"}coldspots{"} are far less likely to occur. There are few if any studies examining how a gradient of increasing trophic complexity might influence the probability of phenotype matching and, correspondingly, the {"} temperature{"} of the coevolutionary interaction. This study was conducted to compare outcomes of the interaction between wild parsnip (Pastinaca sativa) and parsnip webworm (Depressaria pastinacella) in its indigenous area, Europe, to its area of introduction, the midwestern United States. Specifically, we tested the hypothesis that increasing trophic complexity, represented by alternate host plants or the presence of natural enemies, reduces the selective impact of parsnip webworms and hence diminishes linkage between host plant chemistry and webworms that would be expected in coevolutionary hotspots. This comparison of a two-species interaction in its area of introduction and its area of indigeneity revealed common patterns that are more reflective of interaction temperature than of continental origin. Where webworms are rare, parsnips produce lower levels of xanthotoxin and bergapten in both the midwestern United States and Netherlands populations. However, the most striking result from this intercontinental comparison is that what is a ubiquitous two-species interaction in North America is in fact exceptional in Europe; webworms could more reliably be found infesting H. sphondylium even where P. sativa was available as well. This preference for H. sphondylium exists despite the comparatively high probability of parasitism associated with this host plant and may reflect the overall lower furanocoumarin content of H. sphondylium. The interaction of parsnip webworms and wild parsnips at home and away demonstrates clearly the potential for rapid contemporary evolution of chemical traits upon re-association with a coevolved enemy, a potential evolutionary outcome that should be considered in the design and implementation of future weed biological control programs.",
keywords = "Coevolution, Defense, Depressaria pastinacella, Furanocoumarin, Geographic mosaic, Heracleum, Insect-plant interaction, Pastinaca, Trophic complexity",
author = "Berenbaum, {May R.} and Zangerl, {Arthur R.}",
doi = "10.1890/0012-9658(2006)87[3070:PWAHPA]2.0.CO;2",
journal = "Ecology",
publisher = "Ecological Society of America",
T1 - Parsnip webworms and host plants at home and abroad
T2 - Trophic complexity in a geographic mosaic
AU - Berenbaum, May R.
AU - Zangerl, Arthur R.
N2 - Due to differences in the structure of communities in which interactions are embedded, the intensity of interactions between species may vary with location; thus, what results from differences in outcomes and in degree of specialization is a geographic mosaic, which provides the raw material for divergent coevolutionary trajectories. Where selection intensity is great, reciprocal responses are likely in so-called "hotspots"; in contrast, where selection pressures are relaxed, reciprocal responses in "coldspots" are far less likely to occur. There are few if any studies examining how a gradient of increasing trophic complexity might influence the probability of phenotype matching and, correspondingly, the " temperature" of the coevolutionary interaction. This study was conducted to compare outcomes of the interaction between wild parsnip (Pastinaca sativa) and parsnip webworm (Depressaria pastinacella) in its indigenous area, Europe, to its area of introduction, the midwestern United States. Specifically, we tested the hypothesis that increasing trophic complexity, represented by alternate host plants or the presence of natural enemies, reduces the selective impact of parsnip webworms and hence diminishes linkage between host plant chemistry and webworms that would be expected in coevolutionary hotspots. This comparison of a two-species interaction in its area of introduction and its area of indigeneity revealed common patterns that are more reflective of interaction temperature than of continental origin. Where webworms are rare, parsnips produce lower levels of xanthotoxin and bergapten in both the midwestern United States and Netherlands populations. However, the most striking result from this intercontinental comparison is that what is a ubiquitous two-species interaction in North America is in fact exceptional in Europe; webworms could more reliably be found infesting H. sphondylium even where P. sativa was available as well. This preference for H. sphondylium exists despite the comparatively high probability of parasitism associated with this host plant and may reflect the overall lower furanocoumarin content of H. sphondylium. The interaction of parsnip webworms and wild parsnips at home and away demonstrates clearly the potential for rapid contemporary evolution of chemical traits upon re-association with a coevolved enemy, a potential evolutionary outcome that should be considered in the design and implementation of future weed biological control programs.
AB - Due to differences in the structure of communities in which interactions are embedded, the intensity of interactions between species may vary with location; thus, what results from differences in outcomes and in degree of specialization is a geographic mosaic, which provides the raw material for divergent coevolutionary trajectories. Where selection intensity is great, reciprocal responses are likely in so-called "hotspots"; in contrast, where selection pressures are relaxed, reciprocal responses in "coldspots" are far less likely to occur. There are few if any studies examining how a gradient of increasing trophic complexity might influence the probability of phenotype matching and, correspondingly, the " temperature" of the coevolutionary interaction. This study was conducted to compare outcomes of the interaction between wild parsnip (Pastinaca sativa) and parsnip webworm (Depressaria pastinacella) in its indigenous area, Europe, to its area of introduction, the midwestern United States. Specifically, we tested the hypothesis that increasing trophic complexity, represented by alternate host plants or the presence of natural enemies, reduces the selective impact of parsnip webworms and hence diminishes linkage between host plant chemistry and webworms that would be expected in coevolutionary hotspots. This comparison of a two-species interaction in its area of introduction and its area of indigeneity revealed common patterns that are more reflective of interaction temperature than of continental origin. Where webworms are rare, parsnips produce lower levels of xanthotoxin and bergapten in both the midwestern United States and Netherlands populations. However, the most striking result from this intercontinental comparison is that what is a ubiquitous two-species interaction in North America is in fact exceptional in Europe; webworms could more reliably be found infesting H. sphondylium even where P. sativa was available as well. This preference for H. sphondylium exists despite the comparatively high probability of parasitism associated with this host plant and may reflect the overall lower furanocoumarin content of H. sphondylium. The interaction of parsnip webworms and wild parsnips at home and away demonstrates clearly the potential for rapid contemporary evolution of chemical traits upon re-association with a coevolved enemy, a potential evolutionary outcome that should be considered in the design and implementation of future weed biological control programs.
KW - Coevolution
KW - Defense
KW - Depressaria pastinacella
KW - Furanocoumarin
KW - Geographic mosaic
KW - Heracleum
KW - Insect-plant interaction
KW - Pastinaca
KW - Trophic complexity
U2 - 10.1890/0012-9658(2006)87[3070:PWAHPA]2.0.CO;2
DO - 10.1890/0012-9658(2006)87[3070:PWAHPA]2.0.CO;2
JO - Ecology
JF - Ecology