Men and women are different. We all know that. But<br >we are only beginning to understand just how different.<br >"Only by regarding males and females as if they were two<br >different species，" says Tim Clutton-Brock， an ecologist<br >from Cambridge University， "are we likely to understand<br >why it is that the sexes differ so widely in anatomy， physi-<br >ology and behavior."<br > Why are men and women different? No one knows for<br >sure. Both biology and society play a part. But which<br >contributes most is hotly debated. In the 70s， writes Christine<br >Gorman in the January 20， 1992 issue of Time， "talk of<br >inborn differences was distinctly unfashionable， even<br >taboo." Differences were seen as socially based， a product<br >of sex role conditioning.<br > Now the pendulum seems to be swinging in the other<br >direction as "the evidence for innate sexual differences...<br >began to mount，" claims Gorman. Anne Moir and David<br >Jessel， the authors of Brain Sex: The Real Difference Between<br >Men & Women， lead the way in this biological revolution<br >saying， "the society we grow up in does affect us， but<br >essentially in reinforcing our natural differences."<br > Other experts still believe upbringing has more influ-<br >ence than genes and that what is perceived as inborn is<br >really residual cultural conditioning. Feminists such as<br >Carol Tavris and Barbara Ehrenreich caution that using<br >such biologically-based assumptions will once again limit<br >the options women have and may have arisen as a reaction<br >to the social changes women have instigated in the last 30<br >years.<br > I don t profess to have all the answers. Chances are the<br >debate will continue to rage; what I ve tried to do is give a<br >balanced perspective， with both sides represented. The<br >very fact of the differences is what intrigues me. My<br >research into gender differences took place over a seven<br >year period， following the publication of my book， The<br >Givers and The Takers. While writing it， I became fascinated<br >by the differences between men and women and collected<br >every article and book I could find on the subject. I came to<br >see that gender generalizations could accurately be made<br >