There exists also appreciable variation in dimensions concerning individuals. Permanent breast advancement in the course of puberty is brought on by estrogens at the side of the growth hormone. Feminine humans are the sole mammals that permanently establish breasts at puberty; all other mammals develop their mammary tissue in the https://grok.com/share/c2hhcmQtMw%3D%3D_5ad6450c-533d-442c-a09c-9f7bce1babfb