Female facial features change subtly throughout the ovulatory cycle and can influence attractiveness ratings.

“the signals that in non-human primates are in the rear are because we're walking upright you can't see that really so now it's kind of in in the face and so these changes that um happen that the ovulatory cycle is reflected in the turgidity how how tight the skin is in the face because it gets a little plumper and a little bit redder and we may not be consciously aware of that but the that that it's there right and it shows up in sort of preference data when when when you ask heterosexual males you know do you you know how attractive is this woman Etc”