X is a bone found in a majority of mammals, including some primates, however absent in humans.
People have used X from different animals to fashion various kinds of tools.
Some historians also argue that it was infact Adam’s X and not the rib which was taken away to give life to Eve.
Solve for X.
Show Answer
Baculum or the penis bone, present in more animals than you think.
Theory:
The loss of the bone in humans, when it is present in our nearest related species the chimpanzee, is thought to be because humans "evolved a mating system in which the male tended to accompany a particular female all the time to try to ensure paternity of her children" which allows for frequent matings of short duration. Observation suggests that primates with a baculum only infrequently encounter females, but engage in longer periods of copulation that the baculum makes possible, thereby maximizing their chances of fathering the female's offspring. Human females exhibit concealed ovulation also known as hidden estrus, meaning it is almost impossible to tell when the female is fertile, so frequent matings would be necessary to ensure paternity
TLDR: Other animals go in and go out, so need a bone to impress. Human tend to stick around, so boning - not that important.
Apparently a good heart was too stiff a competition for the baculum.
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