In the movie What Women Want, the Mel Gibson character gets in touch with his "feminine side" and tries waxing his legs and exfoliating. Who was more uncomfortable with this, men or women? The scriptwriters may not have known that they were portraying the over-the-top version of "gender shift." As you read this, you don't have to wonder if pantyhose come in king size. But, each gender has "feminine" and "masculine" aspects.

Many of these aspects or expectations are constructed by society, are based in our - or others' - culture(s). Otherwise, why would we have terms such as "tomboy" for rambunctious, tree-climbing girls and "cry baby" for teary-eyed little boys? "Gender shift" isn't for sissies - or about children. "Gender shift" is a dynamic most apt to emerge in our midlife years. What is it? What "happens?" Stated simply, men begin to express and enact their more affective, affiliative aspect, and women tend to become more assertive.

Social scientists can document this anecdotally, but the explanations vary. One school of thought favors a biologically based reasoning; i.e. hormonal changes. Males and females have both estrogen and testosterone in their chemical make up; but, obviously, the percentages are very different. However, as both sexes proceed through the midlife transition, the ratio of estrogen to testosterone changes. When a woman's level of estrogen begins to drop, by ratio, the amount of testosterone in her system is higher; and the converse applies to men. Result: the "testy" female and the "esty" male. Of course, with the application of knowledge building around hormone replacement therapy, this result can be reversed or modified.

Another perspective emerges from considerations of our extended longevity. Maybe the capacity for men to be more affective and for women to be more intentional was always there, but latent. Once both genders began to live past their fifth decade, the opportunities for these capacities to express themselves emerged. For example, anthropologists conjecture that in more primitive societies, (post-)menopausal women could assume positions of authority because the need for them to focus on children and family diminished and, at the same time, their assertiveness surfaced.

You don't have to look too far to see this dynamic in action. Like many "ah ha" moments, it will be small rather than hugely dramatic. One excellent description relates to the situation of the midlife man who wants to talk about buying a bed-and-breakfast while his wife wants to make reservations as a guest at one. If you or a woman you know is talking about starting a new business, getting a law degree, becoming an activist for a cause - that's (her) gender shift. If the husband is, at the same time, thinking about scaling back his work activity, maybe taking up woodworking or serious gardening - that is his gender shift expressing itself. We also see this softening of affect in men who become "second time" fathers - and in many first time grandfathers. Not only are they in a different place in their lives, they are in a different place within themselves.

Western society builds into the male model an expectation of instrumentality - that is, men are expected to "do things." Women are expected to take care of things. When we reach a point where women want to "do" and men want to "care" - that's gender shift at work. What we don't know - and won't know for a while, yet - is if we have to wait for midlife's transitions before this emergence can express itself, or if there is a chance that the "new man" and "new woman" will experience these shifts earlier in their lives.

When I discuss this dynamic in my class The Adult Journey, which is taught to traditional college-aged students, they "get it" immediately. Their parents are, for the majority, in early midlife - so the timing is "right." The students start reporting incidents that are "so that's what that was all about." Their moms are speaking up more, doing their "own thing" more. Their mothers are asking and expecting more from their dads, and their fathers are acceding. Don't get the wrong idea: this isn't a signal that roles have reversed, but some shifting can - and often does - occur. So if you want to get that post-graduate degree and your husband wants to breed a new strain of rose or geranium, both of you can go for it…let gender shift work for you. Climb that tree while he cries about it.