What prospective dad wouldn't want a smart babe to spawn a smart baby? A UC Santa Barbara study suggests that women with thicker backsides and thighs may have a reproductive advantage. Extra fat in these areas contain omega-3 fatty acids to help moms and their baby's brain during pregnancy.
Women beyond childbearing years often loose their 'curves' to an expanding waistline, (this supplies needed estrogen via fat.) Therefore a speculation of anthropologists is the attraction to a woman's 'curves' has to do with healthy reproductive fitness.
A study on men's personalty in reference to women's curves found the men who date a lot and engage in masculine activities, like sports tended to prefer curvy gals. On the other side of the coin, men who liked thin gals with small breast and hips tended to be more money oriented and enjoyed fashion.