| Titre : |
Evolution in thyme enough ? Rapid physiological evolution in response to pollution in two common British plants |
| Type de document : |
texte imprimé |
| Auteurs : |
John Richards, Auteur ; Helena Winsnes, Auteur ; Lynn Whitfield, Auteur |
| Importance : |
pp. 135-148 |
| Langues : |
Anglais (eng) |
| Catégories : |
[Espèces (in biblio)] Lolium perenne
[Espèces (in biblio)] Thymus polytrichus
|
| Mots-clés : |
tolérance |
| Résumé : |
"Speciation is often confused with evolution, but taxonomic recognition of a species depends on morphological distinctiveness. We argue that when plants are challenged by rapid and drastic environmental changes such as those resulting from pollution, climate change, or new predators and pathogens, they commonly show dramatic and often sympatric physiological evolution, but because this is normally cryptic ('silent') it is not recognised by taxonomists and so tends to be ignored by conservationists and policy makers. The principle is illustrated by wild thyme Thymus polytrichus from metal-rich calaminarian grasslands, and perennial rye-grass Lolium perenne from salted road-verges, both of which appear to have evolved tolerance within the last 100 years. Zinc tolerance in T. polytrichus is biparentally dominant. We were unable to detect a metabolic co st to this tolerance, or for salt tolerance found in roadside L. perenne from several sites. We were unable to induce tolerance by early exposure to salt, and strains that appeared to be innate1y tolerant were not later affected by this early exposure. In contrast, susceptible strains showed a 'hang-over' effect from early exposure, even when grown in salt-free conditions." (source : auteurs) |
| Type de publication : |
article de livre |
| Référence biblio : |
Richards J., Winsnes H., Whitfield L., 2006 - Evolution in thyme enough ? Rapid physiological evolution in response to pollution in two common British plants. In : Bailey J., Ellis G., Eds, 2006 - Current taxonomic research on the British & European Flora (Leicester, 13-14 September 2003). London : Botanical Society of the British Isles, 135-148. |
| ID PMB : |
6454 |
| Permalink : |
http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=6454 |
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Evolution in thyme enough ? Rapid physiological evolution in response to pollution in two common British plants