I believe they are learned, for instance today pink is widely considered a "girls color" to the extent that one cant walk through the toy aisles in a store with out seeing a barrage of pink in the toys typically meant of girls. However, before the 20th century in many countries it was the other way around with pink being considered a more masculine color. However in the 1950s, at least in the us, the color pink had become unfailingly associated with femininity. Furthermore, while certain things in sex dependent, ie greater upper body strength in men, and wider hips in women, lead to certain roles in a "primitive" society, hunter and homemaker, this was not a strict standard. Also looking at children, a relatively blank slate, one would notice that alot of behaviors are learned not innate, for example playing with dolls, it is not an odd occurrence to see a young boy play with the dolls of a sister, or playmate, until they are told that dolls are bad "girly" things, and so toy makers responded with "action figures" to satisfy the social norm that boys not play with a "girly" barbie and instead with the "masculine" gi joe.

yes. gender is taught for the most part .