I think it's not that we evolved to be this way in our later years but that after menopause, our biological importance to our species is kind of null. I think that estrogen kept our fat to our thighs and hips and away from the middle of the body as protection during child bearing years. After that time is over, that protection is biologically unnecessary.
That said, the article did mention how this is a problem for women who had no difficulty keeping weight off when younger. I wonder if the study results would be different if they looked at women (like me) who have had to battle the bulge their whole life just to maintain 'normal'? I mean, I don't notice any difference in my ability to maintain my body shape from when I was 18 (still just as difficult!). Other women my age talk about how their metabolism changed after 30 (or whenever).
In my mid-thirties, I had my estrogen shut down for about a year and I was stunned and how quickly my body changed. I didn't get fatter - but the fat distribution changed rapidly. It took some getting used to on my part (because my clothes no longer fit the same), but after awhile, I kind of liked it. I finally had slimmer legs and a waist that would fit into woman's pants without alterations!![]()