Our opinion is that Adam did not lose a rib in the creation of Eve. Any ancient Israelite (or for that matter, any American child) would be expected to know that there is an equal (and even) number of ribs in both men and women. Moreover, ribs lack any intrinsic generative capacity. We think it is far more probable that it was Adam’s baculum that was removed in order to make Eve. That would explain why human males, of all the primates and most other mammals, did not have one. The Hebrew noun translated as “rib,” tzela (tzade, lamed, ayin), can indeed mean a costal rib. It can also mean the rib of a hill (2 Samuel 16:13), the side chambers (enclosing the temple like ribs, as in 1 Kings 6:5,6), or the supporting columns of trees, like cedars or firs, or the planks in buildings and doors (1 Kings 6:15,16). So the word could be used to indicate a structural support beam. Interestingly, Biblical Hebrew, unlike later rabbinic Hebrew, had no technical term for the penis and referred to it through many circumlocutions.While almost any piece of biblical text in Hebrew leaves room for many good interpretations this particular one is motivated by an assumption that the passage in Genesis 2 seeks to offer a mythical explanation for a contemporary element of human anatomy. Their rationalization that Hebrews would have known that men and women have an equal number of ribs (while many modern Christians do not and perpetuate the modern myth that men have less ribs than women based on this passage; did you ever hear that in your Sunday school?) shows their expectations for the intentions of this passage. One would assume a reader ought to read the passage for itself to see what it actually explains before imposing an objective onto it. If ancient Hebrews knew enough about biology to know that men and women had an equal number of ribs then they surely knew that when a father was missing a part of his anatomy his children were still born with it. If one is determined to draw a mythical explanation of modern anatomy from this passage then a baculum explanation has just as many problems in this respect as a rib.
It is possible that the Hebrew word tzela is a euphemism for a penis bone but I fail to see how that explanation is somehow more likely than a rib. An interpretation seeing an explanation of modern anatomy is unnecessary when either body shows that the author of Genesis 2 is asserting that women were made from a part of man making them suitable partners and setting the standard that man and women are supposed to be together. Adding the explanation of the missing baculum in humans unnecessarily clutters the passage and is risky because of the memetic value of the fact. People are apt to find almost any phallic interpretation of a Biblical passage interesting and memorable regardless of any evidence for that interpretation.
