Originally Posted by Count Turnipsome
In apes, does sexual attraction to breasts have an adaptive value?
I do not know since I'm not an ape. You will have to ask the apes that one grin

Originally Posted by Count Turnipsome
Are human female breasts sexually attractive only because of social conditioning?
It seems to me that breasts in female humans could have a number of different possible adaptive values, and because of this it seems logical that the perception of them as sexually attractive is at least partially hardwired, and not entirely socially motivated.
Yes and no. Kinda. The question has quite a broad answer, but I think your last question covers that.

Sexuality definitely can and is influenced by society, but at our cores as a human race; a woman is attractive to a man, just like a man is attractive to a woman. It is an instinctive evolutionary biological imprint and a part of our DNA as a race. And being sexually attracted to someone is completely fine, to which body parts depends entirely on the person. However... the issue arises if that sexual attraction starts affecting a woman in a negative way, which at that point it stops being fine.

Which is the case with humanity throughout history that still follows to this day. The sexual attraction coming from men is negatively impacting women, but because of this attraction women are the ones who keep having rules and laws imposed upon them. So they are being punished for something they cannot control whatsoever, because the problem does not originate from them, but from men.

Originally Posted by Count Turnipsome
One related question. In human societies where breasts are not taboo, are they considered desirable in some proportion of males in those societies?
Actually pretty damn good question. The answer is no in general.

The tribes and even modern parts of the world where bare-chested women are a completely normal everyday thing do not find breasts sexually attractive on their own. When something is common and normal and loses its mystery, it stops being exotic.

In modern society however, the huge part of why someone might find someone attractive is mystery, but also the way one presents themselves. Mystery is exotic and sexy and curious, which makes things that cannot be seen highly attractive and amplifies that sexual drive because it makes the mind wonder.

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