Yes, it’s human (read: mammal) nature for the male of the species to evaluate females with respect to their suitability for mating & childbearing. Curvaceous figures typically indicate fecundity. Why men have been attracted to such as Jean Harlow, Marilyn Monroe, Raquel Welch, Beyonce, J-Lo, Kaley Cuoco (Big Bang, yeah!). Stupid, ugly, undesirable Femi-Nazis.
Here’s what I don’t get though. It has been scientifically deduced that the male human is attracted to high waist/hip ratio, etc. because that signals fertility (propensity to bear healthy children) when in fact that’s not true. I have known very fertile women who don’t fit that mold, as we all have, one is an Aunt who was very short and very slim with narrow pelvis and small breasts but had 8 healthy children.
As for the male gaze, never really gave it a second thought when it used to happen (maybe cause I’ve been married my whole adult life ugh) but now that I’ve passed 40 I’ll admit I notice its absence and it’s a bit sad because it’s like all of a sudden you’re invisible.
Also beautiful faces: pink cheeks, pretty teeth, large, clear eyes, all indicate youth and good health - strong reasons for procreation.