@article {1976,
	title = {Exploring the genetic basis and proximate causes of female fertility advantage in gynodioecious Thymus vulgaris},
	journal = {Evolution},
	volume = {54},
	year = {2000},
	note = {PT: J},
	month = {2000/10//},
	pages = {1510 - 1520},
	abstract = {In many gynodioecous species, females produce more viable seeds than hermaphrodites. Knowledge of the relative contribution of inbreeding depression in hermaphrodites and maternal sex effects to the female fertility advantage and the genetic basis of variation in female fertility advantage is central to our understanding of the evolution of gender specialization. In this study we examine the relative contribution of inbreeding and maternal sex to the female fertility advantage in gynodioecious Thymus vulgaris and quantify whether there is genetically based variation in female fertility advantage for plants from four populations. Following controlled self and outcross (sib, within population, and between-population) pollination, females had a more than twofold fertility advantage (based on the number of germinating seeds per fruit), regardless of the population of origin and the type of pollination. Inbreeding depression on viable seed production by hermaphrodites occurred in two populations, where inbreeding had been previously detected. Biparental inbreeding depression on viable seed production occurred in three of four populations for females, but in only one population for hermaphrodites. Whereas the maternal sex effect may consistently enhance female fertility advantage, inbreeding effects may be limited to particular population contexts where inbreeding may occur. A significant family X maternal sex interaction effect on viable seed production was observed, illustrating that the extent of female fertility advantage varies significantly among families. This result is due to greater variation in hermaphrodite (relative to female) seed fertility between families. Despite this genetic variation in female fertility advantage and the highly female biased sex ratios in populations of T. vulgaris, gynodioecy is a stable polymorphism, suggesting that strong genetic and/or ecological constraints influence the stability of this polymorphism.},
	author = {Thompson, J D and Tarayre, M}
}
@article {1970,
	title = {Population genetic structure of the gynodioecious Thymus vulgaris L. (Labiatae) in southern France},
	journal = {Journal of Evolutionary Biology},
	volume = {10},
	year = {1997},
	note = {From Duplicate 2 (                           Population genetic structure of the gynodioecious Thymus vulgaris L. (Labiatae) in southern France                         - Tarayre, M; Thompson, J D )                
Additional Info: Blackwell Science; 19970301; DOI: 10.1046/j.1420-9101.1997.10020157.x
        
},
	month = {1997/03//},
	pages = {157 - 174},
	publisher = {the journal rests with European Society for Evolutionary Biology},
	abstract = {In a self-compatible gynodioecious species, the abundance of female plants (which are obligate outcrossers) relative to hermaphrodites (which may self and outcross) may be a critical factor influencing genetic diversity and population structure. In the gynodioecious Thymus vulgaris L., female frequency varies from 5 to 95\%, providing a suitable model to examine this issue. In this study, we use allozyme markers to (1) evaluate the relationship between female frequency, genetic diversity and population structure, (2) determine whether females and hermaphrodites vary in heterozygote deficiency and (3) examine whether other factors such as plant density are related to heterozygote deficiency. Twenty three natural populations, with female frequencies ranging from 11 to 92\%, were sampled in and around the St-Martin-de-Londres basin in southern France. Based on four polymorphic allozyme loci, we found no significant correlation between female frequency and heterozygote deficiency. A significant (P < 0.05) F sub(IS) value over loci and over populations of 0.11 was detected. The F sub(IS) value per population showed a significant heterozygote deficiency in 11 of the 23 populations. However, no significant difference between female and hermaphrodite F sub(IS) values was found. A significant heterozygote deficiency only occurred in populations of intermediate density. There was little differentiation among populations (F sub(ST)= 0.038) nor among subpopulations within each population. The significant F sub(IS) values are thus mostly due to inbreeding effects. The lack of a correlation between F sub(IS) values and female frequency may be due to outcrossing in hermaphrodites and/or restoration of male fertility which may occur to a greater extent at low female frequency. The similarity of female and hermaphrodite F sub(IS) values indicates that females may occasion high levels of biparental inbreeding},
	isbn = {1010-061X},
	url = {http://muse.lib.auth.gr:9797/com/csa/?MuseHost=www-mi2.csa.com\&MuseFirst=1\&id=2\&recnum=4\&SID=f6761d6ffa2f8c20dd10ff73e34434f8\&MusePath=\%2Fids70\%2Fview_record.phphttp://muse.lib.auth.gr:9797/com/blackwell-synergy/?MuseHost=www.blackwell-synergy.com\&MuseFir},
	author = {Tarayre, M and Thompson, J D}
}
@article {1974,
	title = {Qualitative and quantitative variation in monoterpene co-occurrence and composition in the essential oil of Thymus vulgaris chemotypes},
	journal = {Journal of Chemical Ecology},
	volume = {29},
	year = {2003},
	note = {From Duplicate 1 (                           Qualitative and quantitative variation in monoterpene co-occurrence and composition in the essential oil of Thymus vulgaris chemotypes                         - Thompson, J D; Chalchat, J C -C; Michet, A; Linhart, Y B; Ehlers, B )                
},
	month = {2003/04//},
	pages = {859 - 880},
	address = {Affiliation: Ctr. d{\textquoteright}Ecologie Fonct. et Evolutive, CNRS, 1919 Route de Mende, 34293 Montpellier Cedex 5, France; Affiliation: Lab. Chim. des Huiles Essentielles, Universite Blaise Pascal de Clermont, Campus des Cézeaux, 24 Avenue des Landais, 63177 Aubie},
	abstract = {Thymus vulgaris has a chemical polymorphism with six different chemotypes that show marked spatial segregation in nature. Although some populations have a single chemotype in majority, many have two or three chemotypes. In this study we analyze the quantitative variation among T. vulgaris populations in the percentage of oil composed of the dominant monoterpene(s) for each chemotype. In general, phenolic chemotypes (thymol and carvacrol), which occur at the end of the biosynthetic chain, have a significantly lower proportion of their oil composed of their dominant monoterpene than nonphenolic chemotypes (geraniol, α-terpineol, and linalool). This is due to the presence of high amounts of precursors (γ-terpinene and paracymene) in the oil of phenolic chemotypes. The essential oil of the nonphenolic thuyanol chemotype has four characteristic monoterpenes that together make up a lower proportion of the oil than the single dominant monoterpene of the other nonphenolic chemotypes. For all chemotypes, the percentage composition of the dominant monoterpene decreased significantly at sites where the chemotype is not the majority type. This decrease is correlated with a significant increase in either the proportion of the two precursors for the thymol chemotype or the monoterpenes characteristic of the other chemotypes at the site. The latter result suggests that a plant with dominant genes is responsible for the production of different monoterpenes can produce several molecules.},
	keywords = {Adaptation, Essential oil composition, Lamiaceae, Mediterranean, Monoterpene production, Polymorphism},
	url = {http://www.scopus.com/scopus/inward/record.url?eid=2-s2.0-0242499958\&partnerID=40\&rel=R6.5.0},
	author = {Thompson, J D and Chalchat, J C -C and Michet, A and Linhart, Y B and Ehlers, B}
}
@article {1975,
	title = {Ongoing adaptation to mediterranean climate extremes in a chemically polymorphic plant},
	journal = {Ecological Monographs},
	volume = {77},
	year = {2007},
	note = {PT: J},
	month = {2007/08//},
	pages = {421 - 439},
	abstract = {Although extreme climatic events may have profound effects on ecological systems. there is a marked lack of information on adaptation to such events. In this study, we employed reciprocal transplantation on both a geographic scale (experimental sites 200 kin apart in different parts of the range of the study species) and a local landscape scale (reciprocal Populations separated by 2-8 km) to study the performance of different chemical forms of Thymus vulgaris which naturally occur in different climatic environments. Survival and growth were analyzed in relation to long-term and contemporary climate data in natural Populations and our experimental sites. The reciprocal transplants involved a period of six years for clones transplanted in experimental field sites on a geographic scale and three years for seedlings transplanted among natural populations at the local landscape level. Cloned transplants on a geographic scale produced evidence for local adaptation to either summer drought, primarily following the extreme summer drought of 2003, or severe early-winter freezing. Chemotypes that show high survival after intense summer drought showed poor survival after intense early-winter freezing and vice versa, results which directly accord with climate data for their original sites. On the local landscape scale, we found further evidence for local adaptation to summer drought but not to winter freezing (probably due to the absence of extreme freezing during the three years of this study). Future modifications to the occurrence and frequency of extreme climate events may have a profound influence on the spatial distribution of thyme chemotypes.},
	author = {Thompson, J D and Gauthier, P and Amiot, J and Ehlers, B K and Collin, C and Fossat, J and Barrios, V and Arnaud-Miramont, F and Keefover-Ring, K and Linhart, Y B}
}
@article {1872,
	title = {A chemical polymorphism in a multitrophic setting: Thyme monoterpene composition and food web structure},
	journal = {American Naturalist},
	volume = {166},
	year = {2005},
	note = {PT: J},
	month = {2005/10//},
	pages = {517 - 529},
	abstract = {We investigated the effects of chemical variation in thyme ( Thymus vulgaris L.) on its interactions with competitors, herbivores, and herbivore predators. Four different thyme monoterpene phenotypes ( chemotypes) were grown in a factorial of chemo- 4 x 2 x 2 type, caging ( sham half-cages vs. full cages), and competition ( control vs. the grass Bromus madritensis L.). Cages reduced numbers of arthropod predators. Thyme-feeding aphids Aphis serpylli Koch passed through full cage walls to increase more than fourfold. As a result, freed from their predators, aphids had a large negative effect on thyme size and flowering. Similarly, competition from Bromus had a negative effect on thyme size and flowering. Individual effects of aphids and competition were nonadditive, however, and their combined effect was significantly less than that predicted by a multiplicative null model. Differential thyme sizes among chemotypes were not mediated by herbivores or competitors, but differential flowering was due to the effects of chemotype on aphids. We thus document differential selection by aphids among thyme chemotypes and the influence of Bromus on the strength of these negative effects of aphids.},
	author = {Linhart, Y B and Keefover-Ring, K and Mooney, K A and Breland, B and Thompson, J D}
}
@article {1873,
	title = {Thyme is of the essence: Biochemical polymorphism and multi-species deterrence},
	journal = {Evolutionary Ecology Research},
	volume = {1},
	year = {1999},
	note = {PT: J},
	month = {1999/02//},
	pages = {151 - 171},
	abstract = {Populations of the common thyme (Thymus vulgaris, Labiatae) are characterized by a complex genetic and biochemical polymorphism. Individual plants manufacture a single dominant monoterpene which gives them a characteristic smell and taste, and the genetic determination of these chemotypes involves a series of five loci interacting with each other in epistatic fashion. We tested the hypothesis that multi-species herbivory and allelopathy are associated with this monoterpene polymorphism. We compared the relative attractiveness and deterrence of various chemotypes by offering either thyme plants or artificial diets laced with monoterpenes to six herbivores: two molluscs, two insects and two mammals. In addition, we summarize experiments by us and others in which bacteria, fungi and seeds of the grass Brachypodium phoenicoides, a common competitor of T. vulgaris, were exposed to the individual monoterpenes. The results show that the monoterpenes have differential deterrence value against these various species. We conclude that a combination of selective herbivory and allelopathy contributes to the maintenance of this polymorphism.},
	author = {Linhart, Y B and Thompson, J D}
}
@article {1874,
	title = {Terpene-based selective herbivory by Helix aspersa (Mollusca) on Thymus vulgaris (Labiatae)},
	journal = {Oecologia},
	volume = {102},
	year = {1995},
	note = {From Duplicate 1 (                           Terpene-Based Selective Herbivory by Helix-Aspersa (Mollusca) on Thymus-Vulgaris (Labiatae)                         - Linhart, Y B; Thompson, J D )                
PT: J
        
},
	month = {1995/04//},
	pages = {126 - 132},
	address = {Affiliation: Univ.CO,Dept Environ.Popul.\& Orgmic Biol., Boulder, CO 80309, United States},
	abstract = {In natural populations of Thymus vulgaris in the south of France, six genetically different chemical {\textquoteright}{\textquoteright}chemotypes{\textquoteright}{\textquoteright} occur, each differentiated by a single dominant monoterpene that gives individual plants a characteristic smell and taste. Individual populations may contain all six chemotypes, but are often dominated by one to three chemotypes. We tested the hypothesis that this chemical polymorphism was associated with selective herbivory by the snail Helix aspersa, which feeds upon T. vulgaris in nature. The relative preference of juvenile and adult molluscs was investigated by presenting individual animals with a choice of six chemotypes in three experimental trials: (1) whole plants, (2) nutritive gels containing crushed thyme leaves, and (3) nutritive gels containing a distilled monoterpene as an additive. We found significant and consistent patterns of preference. Adult and immature molluscs preferred the linalol chemotype, and ate carvacrol and thymol-containing foods the least. This preference was more marked when using the gels than the real plants, particularly the monoterpene-based gels, demonstrating the importance of the monoterpene for the choice. Furthermore, molluscs fed exclusively on linalol-containing food gained weight whereas those fed on carvacrol-containing food lost weight. After being fed these exclusive diets both groups showed a significant preference for linalol. These results (1) demonstrate that food choice is based upon the presence of specific monoterpenes and is not learned, (2) suggest that phenolic monoterpenes such as carvacrol are repellent to the animals, and (3) indicate that selective herbivory may play a significant role in the maintenance of the chemical polymorphism of T. vulgaris.},
	url = {http://www.scopus.com/scopus/inward/record.url?eid=2-s2.0-0028975168\&partnerID=40\&rel=R6.5.0},
	author = {Linhart, Y B and Thompson, J D}
}
@article {1852,
	title = {Multiple genetic contributions to plant performance in Thymus vulgaris},
	journal = {Journal of Ecology},
	volume = {92},
	year = {2004},
	note = {From Duplicate 1 (                           Multiple genetic contributions to plant performance in Thymus vulgaris                         - Thompson, J D; Tarayre, M; Gauthier, P; Litrico, I; Linhart, Y B )                
PT: J
        
      
},
	month = {2004/02//},
	pages = {45 - 56},
	abstract = {1 Diverse genetic factors can affect plant performance. Here we evaluate how maternal and paternal origin, maternal and offspring sexual phenotype and degree of outcrossing jointly influence performance of gynodioecious Thymus vulgaris. 2 In uniform conditions we quantified size and survival of second-generation (G(2)) offspring produced by selfing and outcrossing on the open-pollinated offspring (G(1)) of G(0) females from four populations that differ in sex ratio, selfing rate and chemical type. We controlled for environmental variation, maternal effects and plant age. 3 Offspring with maternal parents from populations dominated by plants that synthesize phenolic monoterpenes had greater survival and size than those from populations with non-phenolic chemotypes. In addition, outcrossing among populations with pollen donors from non-phenolic populations significantly reduced progeny performance. These results suggest chemotype-mediated local adaptation. 4 The progeny of hermaphrodites showed significant inbreeding depression, which despite the pollination treatment x family and pollination treatment x population interactions, showed no consistent variation in relation to population inbreeding levels. 5 For a given level of outcrossing, the progeny of hermaphrodites showed greater among-family and among-population variation in plant size than those of females. Variation in nuclear restorer gene composition across cytoplasmic backgrounds may cause this variation. 6 T. vulgaris, diverse genetic factors jointly affect performance, a result with general implications for understanding fitness variation in natural populations.},
	url = {http://muse.lib.auth.gr:9797/com/blackwell-synergy/?MuseHost=www.blackwell-synergy.com\&MuseFirst=1\&prevSearch=allfield:(thymus+AND+(labiatae+OR+lamiaceae))\&StartMuseCookie=I2KBRCK=1;+path=/;+SERVER=10.0.20.25:8080;+path=/;+JSESSIONID=gbdwEZ34tGZWt4uGDaLvr},
	author = {JohnD.Thompson and MicheleTarayre and PerrineGauthier and IsabelleLitricoandYanB.Linhart and Thompson, J D and Tarayre, M and Gauthier, P and Litrico, I and Linhart, Y B}
}
@article {1799,
	title = {The spatial genetic structure of cytoplasmic (cpDNA) and nuclear (allozyme) markers within and among populations of the gynodioecious Thymus vulgaris (Labiatae) in southern France},
	journal = {American Journal of Botany},
	volume = {84},
	year = {1997},
	note = {From Duplicate 1 (                           The spatial genetic structure of cytoplasmic (cpDNA) and nuclear (allozyme) markers within and among populations of the gynodioecious Thymus vulgaris (Labiatae) in southern France                         - Tarayre, M; Saumitou-Laprade, P; Cuguen, J; Couvet, D; Thompson, J D )                
PT: J
        
      
},
	month = {1997/12//},
	pages = {1675 - 1684},
	abstract = {Recent advances in molecular biology have allowed the development of techniques to contrast spatial differentiation in nuclear and cytoplasmic genes and thus provide important data on relative levels of gene flow by pollen and seed in higher plants. In this paper, we compare the spatial structure of nuclear (allozymes) and cytoplasmic (cpDNA) genes among populations of the gynodioecious Thymus vulgaris in southern France. Based on a combination of three restriction enzymes (CfoI, EcoRV, and PstI), eight chlorotypes (combination of three restriction enzyme patterns revealed by Southern hybridization of Beta vulgaris cpDNA) were identified in the 13 studied populations. One chlorotype was particularly abundant and was detected in nearly all populations. Only one chlorotype was specific to a single population. Up to four different chlorotypes were observed in some populations. An F sub(ST) of 0.238 (P < 0.002) for cpDNA haplotypes indicates spatial structure of cytoplasmic genes among the studied populations. Similar patterns were found within a single young population (CAB) structured in patches and surrounded by a continuous cover of T. vulgaris where the F sub(ST) is 0.546 (P < 0.002). No significant correlation between sex and chlorotype nor between cpDNA diversity and female frequency was detected. Allozyme markers showed markedly less spatial structure (F sub(ST) = 0.021 among populations and 0.019 in the CAB population, P < 0.001). This difference between cpDNA and nuclear allozyme markers suggests that pollen dispersal is more important than seed dispersal both among and within populations},
	isbn = {0002-9122},
	url = {http://muse.lib.auth.gr:9797/com/csa/?MuseHost=www-mi2.csa.com\&MuseFirst=1\&id=2\&recnum=1\&SID=720ce478dc2df80d779b696384a1418e\&MusePath=/ids70/view_record.php},
	author = {Cuguen, J and Couvet, D and Thompson, J D and Tarayre, M and Saumitou-Laprade, P}
}
@article {1710,
	title = {Differential resistance to freezing and spatial distribution in a chemically polymorphic plant Thymus vulgaris},
	journal = {Ecology Letters},
	volume = {8},
	year = {2005},
	note = {PT: J},
	month = {2005/04//},
	pages = {370 - 377},
	abstract = {Secondary compounds play multiple ecological roles. In this study, we present novel experimental evidence of differential tolerance to freezing temperatures among chemotypes of a chemically polymorphic plant, Thymus vulgaris. Non-phenolic chemotypes showed a significantly better survival and re-growth after early-winter freezing (-10 degrees in early December) than phenolic chemotypes. Comparison of temperature data (1971-2002) at a phenolic and non-phenolic site showed that whereas early-winter freezing occurred in 6 years in the non-phenolic site they never occurred at the phenolic site. Observations of trichome morphology (where the essential oil is stocked) with and without intense freezing indicate that non-phenolic chemotypes may escape any negative effects of freezing by releasing their essential oil into the atmosphere during severe freezing. The correlation between tolerance of freezing and local temperature regimes strongly suggests that differential freezing resistance is a key ingredient of the distribution of thyme chemotypes in space.},
	author = {Amiot, J and Salmon, Y and Collin, C and Thompson, J D}
}
