As more and more scientific research is conducted on the study of pre-natal genetics and the hormonal development of the fetus, the understanding of modern science regarding intersexuality is becoming increasingly similar to the Vedic concept of a third sex or "tritiya-prakriti."
The Vedic concept implies, quite simply, that the two male and female natures sometime combine to form a third; one that is inherently different from the original two.
In modern science it was originally believed that males possessed only xy chromosomes and females xx ones. We are now learning, however, that no male or female body is made entirely of one group of chromosomes and that in some instances, the male and female chromosomes become mixed enough to produce subtle and sometimes striking changes in the development of the human body and mind.
The study of intersexuality is very new and has only recently begun to make a lot of surprising and interesting discoveries regarding sexual behavior and orientation. Intersexuality produces a myriad of physical conditions ranging from undescended testicles all the way up to the actual combination of the male and female sex organs (hermophroditism). It is also now suspected that subtle hormonal changes within the developing fetal brain may also cause various types of psychological conditions as well as life-long, male/female sexual orientations such as homosexuality, transgenderism and bisexuality. Indeed, these various "alternative" natures may actually be the most common forms of intersexuality we know. This would explain why Vedic science classified homosexuals and asexuals together and often used the same terms to describe them such as "napumsaka," "sandha," "kliba," etc.
Bisexuality is believed to naturally occur within approximately 15% of the population, homosexuality around 5%, transgenderism .1% and asexuality (producing physical sterility, dysfunction or malformed sex organs) at approximately .036%.
It is already known that several types of physically intersexed conditions produce people who have a 30-40% likelihood of becoming homosexually oriented. In laboratory studies, scientists have been able to produce "lesbian" rats that mount other females by "washing" their developing fetal brains with male hormones. This would indicate that transgendered males, for instance, who have always thought and considered themselves female, may have been biologically "feminized" since pregnancy. The inner, primeval functions of the brain are still a great mystery to science, what to speak of its very early stages of development within the fetus. While much more study needs to be done in this regard, all research conducted so far seems to indicate that sexuality and gender identity are indeed biologically rooted and not simply a matter of "moral choices" or "bad upbringing."
Once again modern science is beginning to understand what ancient Vedic wisdom has known all along---that is, the existence and acceptance of a natural third gender.
For more information on the science of intersexuality, go to the Intersex
Society of North America at:
http://www.isna.org
Hare Krishna!
-Amara dasa