In a study published in the journal Science, an international team of researchers has revealed that a specific type of sugar in the outer covering of the "sticky" egg helps a sperm to adhere and start the fertilization process.
The male hubara bustard ('Chlamydotis undulata') has ornamental feathers that it unfurls flamboyantly as it runs to attract a mate. However, this form of courtship comes at a significant cost. Birds that exhibit this behavior age faster, according to a study published in the journal 'Ecology Letters'.
Vitamin D is important for reproduction in both animals and humans. Scientists from the University of Copenhagen (Denmark) have shown that the higher the levels of vitamin D in the blood, the greater the mobility of human sperm, and the faster they advance.
Around 15 eggs is the ideal amount to achieve a birth by in vitro fertilization and avoid complications, according to a study published in the latest issue of the journal 'Human Reprodution'.
Researchers at the University of Yokohama (Japan) have succeeded in producing sperm in the laboratory from tissue from the testis of mice. The advance, which is presented in the journal 'Nature', opens the doors to new treatments to combat male infertility.
From a biological point of view yes, according to a study published in the journal 'BMC Evolutionary Biology'. Its authors, from the Center for Evolutionary Biology at the University of Western Australia, demonstrated through a series of experiments with domestic mice that the sperm of polygamous rodents compete better in the race for fertilization than that of monogamous rodents.
His mother, a 42-year-old American, had undergone unsuccessful fertility treatments for the past decade. Last year, his doctors presented him with a final option: to implant two embryos that had been frozen for almost 19 years and 7 months, donated by an anonymous couple.
In a study carried out with guppy fish, scientists in Australia have found evidence that less attractive males have better sperm quality. Research shows that the most striking and lushly colored specimens biologically "invest" in their appearance by sacrificing their fertility.
Danni Büchner is invited to Sam Dylan's Halloween party. But the "Goodbye Germany" emigrant has no desire for many other party guests. And find clear words.
