In D. affinis "sex ratio" (sr), a form of meiotic drive characterized by the production of mostly or only female progeny by certain males, is associated with two different X chromosome sequences, XS-I XL-II and XS-II XL-IV. The behavior of the two sequences differed, depending on the Y chromosome constitution, being either Y(L) or 0. Males with sequence XS-II XL-IV and Y(L) produced progenies w...

Maternal sex ratio distorters (MSDs) are selfish elements that enhance their transmission by biasing their host's sex allocation in favor of females. While previous models have predicted that the female-biased populations resulting from sex ratio distortion can benefit from enhanced productivity, these models neglect Fisherian selection for nuclear suppressors, an unrealistic assumption in most...

There is evidence that the ratio of the length of the 2nd and 4th digit (2D:4D) is negatively related to prenatal and adult concentrations of testosterone. It has also been reported that high levels of testosterone at conception in both fathers and mothers are associated with an increased sex ratio (proportion of males at birth). It follows from these observations that low values of 2D:4D may b...

Background Although there are different ways to achieve the desired sex of the fetus, most of those are not completely effective. This paper reports a study on human to check the theories which hypothesize that high potassium maternal diet, douching with alkaline substance to change vaginal PH and intercourse around ovulation affects the sex ratio of the progeny MaterialsAndMethods A quasi-expe...

this study reports the length-weight relationship (lwr), fulton's condition factor ( k ), and sex ratio of the non-native catfish hoplosternum littorale (hancock, 1828) in florida for the first time. sampling was conducted from november 2013 to april 2014 in tosohatchee wildlife management area in christmas, florida. a total of 477 specimens were caught (6.4-13.5 cm tl). the allometric coeffici...

pauesia antennata mukerji (hymenoptera, braconidae) as the unique parasitoid of the giant brown peach aphid, pterochloroides persiace cholodkovsky (hemiptera, aphididae) is considered to be the most effective biological control agent of this pest. in this study, the assessment of selected biological parameters of p. antennata demonstrated that the longevity of mature parasitoid was 3.90 ± 0.22,...