Why are females the default sex of the human species?

Females are often considered the default sex in human development because, in the absence of specific male-determining factors, a fetus will develop female characteristics. This is largely due to the presence of two X chromosomes, which carry genes necessary for female development, while males have one X and one Y chromosome, with the Y chromosome triggering male-specific traits. Additionally, the early stages of embryonic development show that all embryos initially follow a female developmental pathway before any male-specific changes occur. This biological basis supports the idea that females can be seen as the default sex in the absence of male influences.