The prevalence of sexual reproduction remains one of the most perplexing phenomena in evolutionary biology. The deterministic mutation hypothesis postulates that sexual reproduction will be advantageous under synergistic epistasis, a condition in which mutations cause a greater reduction in fitness when combined than would be expected from their individual effects. The inverse condition, antago...

How insect herbivores affect plant performance is of central importance to basic and applied ecology. A full understanding of herbivore effects on plant performance requires understanding interactions (if any) of herbivore effects with plant density and size because these interactions will be critical for determining how herbivores influence plant population size. However, few studies have cons...

in this study, 54 five-year-old farmed female beluga at stage ii of sexual maturation were treated with 0 (control), 0.2, 0.4, 0.8 and 1.6 g of dietary soy equol (eq) and genistein (ge) per each kilogram (kg) of diet during a year. blood samples were collected and ovarian biopsy was performed quarterly. results showed that 64.4% of the huso huso sexually matured at eq 0.4 g/kg and reached stage...

we reportedhere data from a productivity veterinary service that was participatory planned and delivered on farms at the kanihari union belongs to mymensingh district of bangladesh. we used a set of five forms and a breeding calendar on farm visit once in a month to guide service delivery and acquisition of data and to keep the records on general cattle health, reproduction, udder health and fe...

the reproductive biology of the iranian cichlid, iranocichla hormuzensis coad, 1988, was investigated for 13 consecutive months in lower mehran river, from august 2008 through august 2009. four hundred and eighty six individuals (252 males and 234 females) were captured using a seine net (5 mm mesh size). the observed sex ratio was 1m: 0.93f (χ², df = 1, p = 0.414). mean ± sd of total length (t...

background: the initial step in the diagnostic investigation of male infertility has been traditionally based on the conventional seminal profile. however, there are significant limitations regarding its ability to determine the underlying mechanisms that cause the disorder. sperm dna fragmentation has emerged as a potential causative factor of reproductive failure and its assessment has been s...

background: momordica charantia (m. charantia) seed has been supposed to have an antifertility property but mechanisms underlying the infertility effect have not been investigated. objective: we investigated the antifertility effect of m. charantia ethanol seed extracts on reproductive toxicology and seminal and plasma testosterone in male wistar rats. materials and methods: the control group (...

Sexual reproduction and dispersal are often coupled in organisms mixing sexual and asexual reproduction, such as fungi. The aim of this study is to evaluate the impact of mate limitation on the spreading speed of fungal plant parasites. Starting from a simple model with two coupled partial differential equations, we take advantage of the fact that we are interested in the dynamics over large sp...