what is the scientific basis to say there are only two sexes in the human species
The scientific basis for stating that there are only two sexes in the human species is based on genetics and reproductive biology. Humans, like other mammals, have two types of gametes (sex cells) - sperm and ova - that combine during sexual reproduction to form a zygote, which develops into an embryo and eventually a fetus. The biological sex of an individual is determined by the presence of either an X or Y chromosome in their sex chromosomes.Individuals with two X chromosomes (XX) are typically female, while those with one X and one Y chromosome (XY) are typically male. While variations in sex chromosomes (such as XXY or XXX) can occur, they are relatively rare and usually result in conditions such as Klinefelter syndrome or Turner syndrome.Additionally, there are certain physical and physiological differences between male and female humans that are determined by their sex chromosomes, including differences in reproductive anatomy and function, hormone production, and secondary sex characteristics.
