Natural Hybrid Orbital (NHO)

Abstract Genetic analyses of reproductive barriers represent one of the few methods by which theories of speciation can be tested. However, genetic study is often restricted to model organisms that have short generation times and are easily propagated in the laboratory. Replicate hybrid zones with a diversity of recombinant genotypes of varying age offer increased resolution for genetic mapping experiments and expand the pool of organisms amenable to genetic study. Using 88 markers distributed across 17 chromosomes, we analyze the introgression of chromosomal segments of Helianthus petiolaris into H. annuus in three natural hybrid zones. Introgression was significantly reduced relative to neutral expectations for 26 chromosomal segments, suggesting that each segment contains one or more factors that contribute to isolation. Pollen sterility is significantly associated with 16 of these 26 segments, providing a straightforward explanation of why this subset of blocks is disadvantageous in hybrids. In addition, comparison of rates of introgression across colinear vs. rearranged chromosomes indicates that close to 50% of the barrier to introgression is due to chromosomal rearrangements. These results demonstrate the utility of hybrid zones for identifying factors contributing to isolation and verify the prediction of increased resolution relative to controlled crosses.

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Sedum ×estrelae(Gideon F.Sm. & R.Stephenson) Gideon F.Sm. (Crassulaceae): A New Combination for a Natural Hybrid inSedumSeriesRupestriaA.Berger (=PetrosedumGrulich) from Portugal

Haseltonia ◽

10.2985/026.021.0114 ◽

2015 ◽

Vol 21 ◽

pp. 95-96

Author(s):

Gideon F. Smith

Keyword(s):

New Combination ◽

Natural Hybrid

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The shape of an octahedral hybrid orbital

Chemical Physics Letters ◽

10.1016/0009-2614(70)80101-4 ◽

1970 ◽

Vol 4 (10) ◽

pp. 625-626 ◽

Cited By ~ 4

Author(s):

L.L. Boyle

Keyword(s):

Hybrid Orbital

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Endoparasitic helminths of water frog complex in Poland: do differences exist between the parental species Pelophylax ridibundus and Pelophylax lessonae, and their natural hybrid Pelophylax esculentus?

Helminthologia ◽

10.2478/s11687-011-0020-8 ◽

2011 ◽

Vol 48 (2) ◽

pp. 108-115 ◽

Cited By ~ 4

Author(s):

M. Popiołek ◽

B. Rozenblut-Kościsty ◽

M. Kot ◽

W. Nosal ◽

M. Ogielska

Keyword(s):

20Th Century ◽

Parental Species ◽

Helminth Species ◽

Natural Hybrid ◽

Intensity Of Infection ◽

Water Frog ◽

Pelophylax Ridibundus ◽

Water Frogs ◽

Pelophylax Esculentus ◽

Cosmocerca Ornata

AbstractParasitic fauna of water frogs was mainly studied in the second half of the 20th century. However, these studies were done without differentiation into species and hybrids and pooled the 3 taxa as “water frogs” or “green frogs”. The aim of this study was to make an inventory of helminth species as well as their prevalence and intensity of infection in the two parental species (Pelophylax ridibundus and P. lessonae) and the hybrid (P. esculentus) of water frogs from 3 big populations composed of hundreds or thousands of individuals inhabited natural and seminatural landscapes in Poland. Eight helminth species were found: Polystoma integerrimum, Diplodiscus subclavatus, Opisthoglyphe ranae, Gorgodera cygnoides, Haematoloechus variegatus, Oswaldocruzia filiformis, Cosmocerca ornata and Acanthocephalus ranae. The results were compared with data from other, polish and European studies. Additionally we compared the level of infection among water frog taxa.

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Iris revolutaColas., natural hybrid origin species: characterization and preservation problems

Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology ◽

10.1080/11263500701872986 ◽

2008 ◽

Vol 142 (1) ◽

pp. 162-165

Author(s):

R. Accogli ◽

E. Nutricati ◽

L. Famà ◽

P. Medagli ◽

D. Manno ◽

...

Keyword(s):

Hybrid Origin ◽

Natural Hybrid

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