While most animals reproduce sexually, some species rely solely on females for parthenogenetic reproduction. Even in these species, rare males occasionally appear. Whether these males retain ...

Mayer is medical research director and co-chair of The Fenway Institute as well as a professor of medicine at Harvard Medical School. Every day, there are 1 million new cases of potentially curable ...

In the debate over human origins and the nature of sexual reproduction, religious and scientific perspectives often diverge. The Bible claims man came first, with women derived from man’s rib. Yet, ...

Sex ratio dynamics refer to the evolutionary and ecological processes by which organisms bias the proportion of male and female offspring. At the heart of this field lie theoretical frameworks such as ...

It’s not just about chromosomes. Or reproductive cells. Or any other binary metric. Many genetic, environmental and developmental variations can produce what are thought of as masculine and feminine ...