In the past girls and boys have been treated differently and have taken on different roles and interests. Currently, there is emphasis on treating boys and girls in the same way and for them to have equal opportunities in their lives.
However, children still seem to be attracted to traditional aspects of the roles for their sex. Rebecca shows a great deal of interest in looks and has a strong preference for wearing clothes that signal her gender, such as wearing pink.
One interpretation of Rebecca's preferences and interests might be that they are caused by girls inheriting a different set of preferences to boys. According to this argument, the different roles of men and women have resulted in the survival of women and their offspring who have certain characteristics, and so these characteristics have become more common in the population as a whole.
Following this line of thought, girls might be more concerned with appearance because in our evolutionary past it has been important for both their status and finding an effective 'mate'.
A different interpretation of Rebecca's preference and interests could be that they have been moulded by her environment. Rebecca's mother initially says she does not want a girl. However, her mother is obviously pleased with the news that her baby is a girl.
Later on Rebecca is given the traditional pink of a baby girl, and when Rebecca is older there is a shared mother-daughter interest in shopping and concern about appearance. In addition, Rebecca grows up in a family with her mother adopting a traditional role, and there being emphasis in her nursery and school on different roles for girls and boys.
But it's unlikely that either of these simple explanations is true; the picture is almost certainly much more complex. Probably, most authorities would say that both genetic make up and environmental influences together result in the differences we see between boys and girls, but there are widely different views about the extent of each of these sets of influence.
The problem is that is has been impossible to set up the unbiased experiments that would be needed to test these different ideas. Even in families that try to ignore traditional roles for boys and girls there still remains the wider influence of the prevailing culture.
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