The Adaptive Value of Male-Biased Sex Ratios Among Stressed Animals

1984 ◽  
Vol 124 (4) ◽  
pp. 597-599 ◽  
Author(s):  
Mark A. McGinley
Keyword(s):  
Sex Ratios ◽  
Adaptive Value

Translocation heterozygosity in southern African species of Viscum

Bothalia ◽  
1980 ◽  
Vol 13 (1/2) ◽  
pp. 161-169 ◽  
Author(s):  
D. Wiens ◽  
B. A. Barlow
Keyword(s):  
Sex Ratios ◽  
Meiotic Drive ◽  
Sex Factors ◽  
Structural Rearrangements ◽  
Dioecious Species ◽  
African Species ◽  
High Frequencies ◽  
Supernumerary Chromosomes ◽  
Adaptive Value ◽  
Translocation Heterozygosity

Sex-associated and floating translocation complexes are characteristic of dioecious species of  Viscum,  but are virtually absent in monoecious species. The majority of dioecious species has fixed sex-associated translocation complexes with the male being the heterozygous sex. The sex-associated multivalent is usually O4 (ring-of-four) or O6 , rarely O8 . Dioecious species without sex-associated translocations are much less common. Most of the dioecious species are also polymorphic for floating translocations, producing one or more additional multivalents ranging from O4 to O12. Floating translocations may be more frequent in species that do not have sex-associated translocations. Supernumerary chromosomes are also present in several species. Sex ratios are at unity in most dioecious species, but female-biased ratios may occur in some species. The high correlation between dioecy and translocation heterozygosity suggests that translocations are primarily associated with the origin and establishment of dioecy. Any róle in the maintenance of biased sex ratios through meiotic drive is probably secondary. Sex-associated translocations may serve to stabilize dioecy by bringing the sex factors into close linkage. Subsequent structural rearrangements within a sex-associated translocation complex may bring the sex factors together in one chromosome pair, releasing floating translocations. The high frequencies of floating translocation heterozygosity in some species indicate that such heterozygosity also has adaptive value.

Expression Unlocks Gratitude's Adaptive Value

2013 ◽  
Author(s):  
Sara B. Algoe
Keyword(s):  
Adaptive Value

Trait self-enhancement: Moderators of the adaptive value

2007 ◽  
Author(s):  
Delroy L. Paulhus ◽  
Aliye Kurt ◽  
Jennifer D. Campbell
Keyword(s):  
Adaptive Value

Spatiotemporal sex ratios of a dioecious marine green alga Monostroma latissimum (Kütz.) Wittr.

2009 ◽  
Vol 11 (2) ◽  
pp. 141-150 ◽  
Author(s):  
F. Bast ◽  
M. Hiraoka ◽  
K. Okuda
Keyword(s):  
Green Alga ◽  
Sex Ratios ◽  
Monostroma Latissimum ◽  
Marine Green Alga

Conservation Status and Sex Ratios of the Coahuila Box Turtle (Terrapene coahuila) in the Cuatro Ciénegas Valley of Coahuila, Mexico, 2011–2018

2020 ◽  
Vol 19 (1) ◽  
pp. 14
Author(s):  
Gamaliel Castañeda Gaytan ◽  
Ernesto Becerra-López ◽  
Sara Valenzuela-Ceballos ◽  
Miguel Borja-Jiménez ◽  
Bruno Rodríguez-López ◽  
...  
Keyword(s):  
Conservation Status ◽  
Sex Ratios ◽  
Box Turtle ◽  
Cuatro Ciénegas
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