Taboo and Genetics | Page 9

the somatic cells are organized around the germ cells, as pointed out above. Hence the sex glands may be considered as the keys or central factors in the two chemical systems, the male and the female type.
These various hormones or chemical controllers in the blood interact in a nicely balanced chemical system. Taken as a whole this is often called the "secretory balance" or "internal secretory balance." This balance is literally the key to the sex differences we see, because it lies back of them; i.e., there are two general types of secretory balance, one for males and one for females. Not only are the secretions from the male and the female sex glands themselves quite unlike, but the whole chemical system, balance or "complex" involved is different. Because of this dual basis for metabolism or body chemistry, centering in the sex glands, no organ or cell in a male body can be exactly like the corresponding one in a female body.
In highly organized forms like the mammals (including man), sex is linked up with all the internal secretions, and hence is of the whole body.[3] As Bell [2, p.5] states it: "We must focus at one and the same time the two essential processes of life--the individual metabolism and the reproductive metabolism. They are interdependent. Indeed, the individual metabolism is the reproductive metabolism."
Here, then, is the reason men have larger, differently formed bodies than women--why they have heavier bones, tend to grow beards, and so on. The sex glands are only part of what we may call a well-organized chemical laboratory, delivering various products to the blood, but always in the same general proportions for a given sex. The ingredients which come from the sex glands are also qualitatively different, as has been repeatedly proved by injections and otherwise.
Each of these sex types, male and female, varies somewhat within itself, as is true of everything living. The two are not so far apart but that they may overlap occasionally in some details. For instance, some women are larger than are some men--have lower pitched voices, etc. The whole bodily metabolism, resting as it does upon a chemical complex, is obviously more like the male average in some women than it is in others, and vice versa. But the average physical make-up which we find associated with the male and female sex glands, respectively, is distinctive in each case, and a vast majority of individuals of each sex conform nearly enough to the average so that classification presents no difficulty.
The extreme as well as the average body types existing in the presence of the respective types of sex-glands are different. For example, we find an occasional hen with male spurs, comb or wattles, though she is a normal female in every other respect, and lays eggs.[4] But we never find a functional female (which lays eggs) with all the typical characteristics of the male body. Body variation can go only so far in the presence of each type of primary sexuality (i.e., sex-glands).
The bodily peculiarities of each sex, as distinguished from the sex-glands or gonads themselves, are known as secondary sex characters. To put our statement in the paragraph above in another form, the primary and secondary sex do not always correspond in all details. We shall find as we proceed that our original tentative definition of sex as the ability to produce in the one case sperm, in the other eggs, is sometimes difficult to apply. What shall we say of a sterile individual, which produces neither? The problem is especially embarrassing when the primary and secondary sex do not correspond, as is sometimes the case.
Even in a fully grown animal, to remove or exchange the sex glands (by surgery) modifies the bodily type. One of the most familiar cases of removal is the gelding or desexed horse. His appearance and disposition are different from the stallion, especially if the operation takes place while he is very young. The reason he resembles a normal male in many respects is simply that sexuality in such highly-organized mammals is of the whole body, not of the sex-glands or organs alone.
Suppose this horse was desexed at two years old. Nearly three years had elapsed since he was a fertilized egg. During the eleven months or so he spent within his mother, he developed a very complicated body. Beginning as a male, with a male-type metabolism (that is, as the result of a union between an X and a Y chromosome, not two X's), all his glands, as well as the body structures they control, developed in its presence. Not only the sex glands, but the liver, suprarenals, thyroid--the whole body in fact--became adjusted to the male type. He had long before birth what we call a male sex complex. Complex it is,