Genetic sex introduces variation in phenotypic traits in sexually reproducing organisms. Sexual dimorphism, the phenotypic differences between the two sexes of a species, can be exhibited at various ...

For millions of years, some of Earth’s earliest animals barely changed. They lived, grew, and spread across the seafloor, but ...

In many sexually reproducing organisms, oocytes are fundamentally fertilized with one sperm. In Caenorhabditis elegans, chitin layer formation after fertilization by the EGG complex is one of the ...

Sex is a tricky business, evolutionarily speaking. One problem is that sexually reproducing organisms must suffer the considerable faff of securing a mate (for the males of some species, the struggle ...

Despite the obvious benefits of sex, it's an activity that's biologically disadvantageous under most conditions. Now, a new study published online today (13 October) in Nature helps explain why sex ...