From chapter "Narcissism"
Here is a beautiful thing. As you know, bacteria outnumber human cells in our bodies ten to one. So we need to gain bacteria somehow; they have to come from somewhere. How does this begin to happen? It used to be thought that the placenta is a sterile place, and that babies encounter their first bacteria in the birth canal, where they meet, among others, Lactobacillus johnsonii, who is a milk-digesting bacteria. Normally, not many of these bacteria live in the vagina, but during pregnancy the population of Lactobacillus johnsonii there greatly expands, so that during birth the child is literally covered with them. Some of these bacteria are ingested, and they give the child the ability to absorb the mother’s milk.
That would be beautiful enough, but more recent research shows that the placenta probably isn’t sterile, but that instead, as one article puts it, the “placenta harbours a unique ecosystem of bacteria which may have a surprising origin—the mother’s mouth.” Evidently the bacteria “somehow” (to use the scientific term) make their way from her mouth through her bloodstream and then either into the baby’s bloodstream or into the baby’s mouth and then gut through amniotic fluid. But how does this happen? How do the bacteria make their way? What are the relationships between mother, bacteria, and child? Who is helping whom, and how?
I’m sorry, do you want to tell me again that there is no true function in nature?