And they can and do change sexes. Mike
no propaganda please wrote:
No, female is XX and male is XY, since only one of each pair becomes part of the new generation. Some males do have 2 xx plus the y which causes Klinfelters syndrome, and there are also other types of genetic abnormalities, which can be tested for. Fortunately most cause sterility. What is more interesting is that some species of fish, frogs and toads and turtles the sex is not determined by the genes, but on external factors.