Category: Uncategorized

TRANSGRESSIVE CHARACTERISTICS. “Studies of quantitative traits in segregating hybrid populations sometimes report the presence of phenotypes that are extreme relative to those of either parental line. The generation of these extreme phenotypes is referred to as transgressive segregation, and this is a major mechanism by which extreme or novel adaptations observed in new hybrid ecotypes or species are thought to arise.” https://lnkd.in/d4xXNs5 View in LinkedIn

UNEVEN PLANT HYBRIDIZATION. "There is strong evidence that hybridization does not occur uniformly across all plant families, and hence spontaneous hybridization seems to be more prevalent in certain families and genera. A group with high levels of natural hybridization is Rhododendron. The genus has more than 1000 species, many of which are interfertile." https://lnkd.in/dK-A3iM View in LinkedIn

TRANSGRESSIVE CHARACTERISTICS. “Studies of quantitative traits in segregating hybrid populations sometimes report the presence of phenotypes that are extreme relative to those of either parental line. The generation of these extreme phenotypes is referred to as transgressive segregation, and this is a major mechanism by which extreme or novel adaptations observed in new hybrid ecotypes or species are thought to arise.” https://lnkd.in/d4xXNs5 View in LinkedIn

SPECIES NAMING REVERSALS. "Over time there have been many examples across different genera and families, where a plant described as a new species has been subsequently proven to be a hybrid." https://lnkd.in/dK-A3iM View in LinkedIn

TRANSGRESSIVE PROBLEM. "A further problem can arise from transgressive characters, meaning traits that are not seen in either parent. Transgressive characters can already occur at a lower frequency in F1 hybrids, but are frequently reported in later generation hybrids." https://lnkd.in/dK-A3iM View in LinkedIn

REPRODUCTIVE ISOLATION IS KEY. "Regarding description of hybrids as species, an important distinction should be made between reproductively isolated taxa that originated through hybrid speciation (hybrid species) and continuously re-formed hybrids that have distinct features but do not represent a reproductively isolated lineage." https://lnkd.in/dK-A3iM View in LinkedIn

REASSIGNED RHODODENDRON SPECIES. "Together, the two species investigated here have nine described infraspecific taxa: five for R. delavayi, and four for R. irroratum, however, these are all assigned the rank of subspecies." https://lnkd.in/dK-A3iM View in LinkedIn

MISNAMED PLANT SPECIES. "Despite ongoing debate about the overall evolutionary importance of hybridization, the process has been shown to be widespread and relatively common in plants, occurring across many different families and floras. Indeed, Rieseberg (1997) suggested that a worldwide average of 11 % of all described plant species may be hybrids, and that this figure may even be an underestimate." https://lnkd.in/dK-A3iM View in LinkedIn

CONSERVATIVE TAXA ASSIGNMENT. "Hybrids growing in sympatry with their parents cannot necessarily be assumed to have a distinct genepool, and even if certain hybrids show higher fitness than the parents, it needs to be demonstrated that they have the potential to evolve into a coherent group under natural conditions. Before evidence has been collected in this regard, hybrids should rather be recorded as such rather than described as a taxon." https://lnkd.in/dK-A3iM View in LinkedIn

DISTINCT SPECIES PROPERTIES. "Such properties can, for example, include a distinct genepool or adaptation to a different habitat. Furthermore, the group should already share a common evolutionary history or have the potential to diverge." https://lnkd.in/dK-A3iM View in LinkedIn