Summary
Recent definitions of the botanical terms ecotype, ecospecies and coenospecies are briefly reviewed. Examples of ecospecies are discussed and the following new definitions are proposed:
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g-ecospecies
Groups with the same chromosome number between which there are well-defined morphological, ecological and geographical differences and which, under artifical or natural conditions are capable of only limited gene-exchange.
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a-ecospecies
Groups with different chromosome numbers between which there are well-defined ecological and geographical differences and which are capable of only limited gene-exchange.
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ecotypes
Groups forming genetically distinct components of ecospecies, adapted to special types of environment and capable of unlimited gene-exchange.
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cytotypes
Groups forming polyploid components of an ecospecies.
The probable modes of origin ofg-ecospecies (gradual) anda-ecospecies (abrupt) are explained; and the importance of the recognition by taxonomists ofa-ecospecies, which may differ morphologically hardly at all, is. emphasized.
Examples of the uses of the terms are given, and it is suggested that their application to animals as well as plants would be of interest.
Zusammenfassung
Neuere Definitionen der botanischen Begriffe „ecotype”, „ecospecies” und “coenospecies” werden kurz besprochen. Beispiele von ecospecies werden erörtet, und folgende neue Begriffsbestimmungen vorgeschlagen:
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„g-ecospecies”
Gruppen mit gleicher Chromosomenzahl, zwischen denen morphologische, ökologische und geographische Unterschiede deutlich festzustellen sind, und bei denen in künstlichen oder natürlichen Zuständen nur beschränkter Genaustausch stattfinden kann.
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„a-ecospecies”
Gruppen mit ungleicher Chromosomenzahl, zwischen denen ökologische und geographische Unterschiede deutlich festzustellen sind, und bei denen nur beschränkter Genaustausch stattfinden kann.
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„ecotypes“
Gruppen, die genetisch unterschiedene Bestandteile von ecospecies bilden, die für besondere Typen von Milieu geeignet sind, und bei denen unbeschränkter Genaustausch stattfinden kann.
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„cytotypes“
Gruppen, die polyploiden Bestandteile einer ecospecies bilden.
Die wahrscheinlichen Enstehungsarten derg-ecospecies (allmählich) und dera-ecospecies (plötzlich) werden beschrieben, und es wird für besonders wichtig erklärt, dass die Systematiker den Begriffa-ecospecies anerkennen, denn diese mögen sich morphologisch äusserst wenig unterscheiden.
Beispiele für den Gebrauch der Begriffe werden angeführt, und es wird vorgeschlagen, dass es interessant wäre, sie nicht nur bei Pflanzen sondern auch bei Tieren zu verwenden.
Sommaire
Nous avons brièvement étudié dans l'article ci-dessus les récentes définitions des ternies botaniques „ecotype” „ecospecies”, et „coenospecies”. Nous avons discuté quelques exemples d'ecospecies et nous avons proposé les nouvelles définitions suivantes:
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„g-ecospecies”
Groupes avec le même nombre de chromosomes, entre lesquels il y a des différences morphologiques, écologiques et géographiques nettement déterminées; ils ne sont capables que d'un échange limité de gènes dans des conditions artificielles ou naturelles.
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„a-ecospecies”
Groupes avec différents nombres de chromosomes, entre lesquels il y a des différences écologiques et géographiques nettement déterminées, et qui ne sont capables que d'un échange limité de gènes.
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„ecotypes”
Groupes formant des composants d'ecospecies génétiquement distincts, adaptés à des types spéciaux de milieux et qui sont capables d'un échange illimité de gènes.
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„cytotypes”
Groupes formant des composants polyploïdes d'une ecospecies.
Les origines probables desg-ecospecies (graduelles) et desa-ecospecies (abruptes) y sont expliquées; nous avons mis en relief l'importance de l'identification par les taxonomistes d'a-ecospecies, qui peuvent à peine présenter des différences morphologiques.
Nous donnons des exemples d'emplois de ces termes, et nous suggérons que leurs applications aux animaux aussi bien qu'aux plantes pourraient présenter un intérêt certain.
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Valentine, D.H. The units of experimental taxonomy. Acta Biotheor 9, 75–88 (1949). https://doi.org/10.1007/BF01556761
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DOI: https://doi.org/10.1007/BF01556761