02436nas a2200241   4500008004100000245009100041210006900132260001400201300001400215490000700229520167100236100001901907700001601926700001301942700001701955700001401972700001401986700001502000700002302015700002102038700001802059856011702077       2007                        eng d00aOngoing adaptation to mediterranean climate extremes in a chemically polymorphic plant0 aOngoing adaptation to mediterranean climate extremes in a chemic  c2007/08//  a421 - 4390 v773 aAlthough 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.1 aThompson, J, D1 aGauthier, P1 aAmiot, J1 aEhlers, B, K1 aCollin, C1 aFossat, J1 aBarrios, V1 aArnaud-Miramont, F1 aKeefover-Ring, K1 aLinhart, Y, B  uhttps://thymus.myspecies.info/ref/ongoing-adaptation-mediterranean-climate-extremes-chemically-polymorphic-plant01690nas a2200169   4500008004100000245011500041210006900156260001400225300001400239490000600253520106900259100001301328700001401341700001401355700001901369856013201388       2005                        eng d00aDifferential resistance to freezing and spatial distribution in a chemically polymorphic plant Thymus vulgaris0 aDifferential resistance to freezing and spatial distribution in   c2005/04//  a370 - 3770 v83 aSecondary 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.1 aAmiot, J1 aSalmon, Y1 aCollin, C1 aThompson, J, D  uhttps://thymus.myspecies.info/ref/differential-resistance-freezing-and-spatial-distribution-chemically-polymorphic-plant-thymus