Several decades ago a few people began to wonder why boys and girls, in general, grew up with different preferences. Why, for example, do most girls play with dolls and care about relationships while most boys like to play with trucks or trains and imitate the sounds of machinery? Some thought the answer revolved around the children's environment and the expectations of parents. They theorized that, if boys and girls were not told which toys to play with and if parents would simply refrain from teaching sexual roles, the male-female generalities would disappear.

But they haven't and, apparently, never will.

The more we learn about the human body and mind, the more obvious it becomes that males and females have innate differences. These include the way we think, communicate and survive.

There are the physical differences between males and females, most obvious in the reproductive organs. Other physical differences not so well known include (Gary Smalley, If Only He Knew, 1988, p. 13):

• The cells of men and women have different chromosome makeup.
• Females tend to live longer than males.
• Males have a higher rate of metabolism.
• Men and women have slightly different skeletal structures.
• Women have larger kidneys, livers, stomachs and appendixes.
• Men have larger lungs.
• Women's blood contains more water and 20 percent fewer red cells.
• Men generally have 50 percent more brute strength.
• Women withstand high temperatures better than men.

We also find sex-based difference in the mental makeup of men and women. In general, females develop the left hemisphere of the brain first, have a larger corpus callosum with more fibers, have better verbal and fine motor skills, have 20 to 30 percent higher levels of serotonin (which is linked to low self-confidence and obsessive-compulsive behavior) and spread their thinking over a wider area of the brain (which means fewer learning disabilities).

Males, by contrast, develop the right hemisphere of the brain first. The male hormone testosterone enhances abstract thinking and spatial concepts; the brain is more compartmentalized in usage and has a narrower corpus callosum; and the 20 to 30 percent lower levels of serotonin are linked to aggression, depression and explosive rage.

In ordaining that a man and a woman be joined together in marriage (Genesis 2:24), God established a team that could benefit immensely from the strengths of each sex. Working together in full cooperation, their potential for spiritual growth becomes enormous. Indeed they are heirs together of the grace of life. GN