What is one of the few physiological differences between an XX female and an XY
female?

They formed the oceans.  as they melted water was formed and the water made the oceans

Molecules called lipids have long hydrocarbon chains that determine the way they act. they can be fats, oils, or hormones, and even exist in our cell membranes 

Ascientist will use that to figure out how or why things are the certain way they are i hope this