This seems to be outside the realm of history and more in the realm of anthropology. Archaeology wouldn't give decent results because soft tissue is hard to measure over time and genetics of a phenotype such as breast size is polymorphic and dependent on nutrition.

This seems to be outside the realm of history and more in the realm of anthropology. Archaeology wouldn't give decent results because soft tissue is hard to measure over time and genetics of a phenotype such as breast size is polymorphic and dependent on nutrition.

I don't know about evidence. But I doubt it.

Breast size would already have been accounted for in evolution before human history. Why would the establishment of civilization change our desire?

You could maybe make the case that breasts might have gotten smaller because clothing allows women to make their breasts appear larger than possible. BUT the period of human history we have is so short in the grand scale of evolution, I doubt it makes a significant difference without some serious intentional selective breeding involved.

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Edit: As /u/imgooley pointed out. Nutrition might also play a factor in this. But I doubt selective breeding has any impact.