Growing up, we had 3 books in our household: a bible, a German-English dictionary, and a big honkin’ Family Medical Guide – fully illustrated.
I used to spend hours with that medical book convincing myself I had everything from diphtheria to polio to lock-jaw to ectopic pregnancy. At first, I’d tell my parents about it, but they were always less than sympathetic, so usually I would just suffer in silence, leaving scraps of paper as bookmarks in the medical guide so people would know what I’d died from.
I’ve never lost that fascination with medical stuff. I should be a huge fan of Grey’s Anatomy, House, ER and such, but I’m not because I’ve also never lost the ability to imagine myself into a disease. And these shows feature some weird scary-assed diseases. So that’s probably also why it’s good that I never went to medical school. That and the fact that I rather dislike sick people.
So mostly I content myself with keeping up on medical news. Aside from the odd Ebola scare (that was a tough couple of weeks) or a Creutzfeldt Jakob outbreak (which was one thing I smugly knew I didn’t have), a lot of medical news just involves more drugs or vaccines being pumped into the market.
I like to see what’s going on with stem cell research and therapy, too because it’s always good to know there may be hope for a lot of these things to which one might be susceptible.
And, one of my favourite medical topics (and gee hasn’t it taken a long time to get to the point today) is vestigial structures in the human being.
These are things in or on our bodies that seem to have no purpose; such as nipples on men, the appendix, ear muscles[1], goosebumps[2], body hair, the coccyx (the last remnant of our tail days), facial muscles[3] or wisdom teeth[4]. Vestigials are very controversial because they were used by Darwin as proof of human evolution. Creationists have funded tons of research to prove that all these so-called vestigals do, indeed have a purpose.
At one time evolutionists had identified 180 vestigial structures in humans including the tonsils, the thymus gland, the pineal gland and the appendix – all of which are now known to have some very important functions.
It was only in the last year that the purpose of the appendix was discovered. It was once thought that it was just a shriveled up sac that used to help humans digest cellulose from things like plants and tree bark and as humans became more carnivorous we stopped needing that organ. After blithely yanking out kids’ appendices for decades, they now know that the appendix is a store-house of good gut bacteria that will release its stuff when necessary following a gut-bacteria killing illness like cholera or dysentery.
Male nipples aren’t really vestigials. They’ve never had a use as far as anyone knows. Nipples are formed in the 3rd or 4th week of human development with the fetus is still androgynous. Sex hormones come into play around week 7.
In some other mammals the male sex hormone then suppresses the whole male nipple thing, but not in humans.
Both male and female babies are born with perfectly good milk ducts in their breasts. Males retain this gland but it doesn’t develop unless stimulated by estrogen. Some male babies are born with enough of his mother’s estrogen is his system to actually pump out some milk (it’s bizarre enough to be nicknamed witches’ milk).
In theory it’s possible to provide enough estrogen stimulation to an adult male to produce lactation – it’s been done a couple of times. Who knows where this could lead in the future?
[1] We still have ear muscles that used to be used to move the ears, like a cat’s, and do nothing now.
[2] Goosebumps were useful when we were covered in hair so they’d perk up our body hair when we got cold adding a layer of insulating air between hair follicles. Or, perking up the body hair when we got scared, making us look a little bigger and fiercer to scare away enemies.
[3] We still have the face muscles that used to hold up our heads, like they do in gorillas, but now we just use them for facial expression.
[4] Wisdom teeth are left over from when we had much bigger jaws and needed extra teeth to chew raw stuff. That seems like a pretty lame explanation to me, but that’s the best anyone could come up with so far.
