musingsonwomenshealth.com

Reflections on 40 years as a doctor in Women's Health

Who are you?


I suppose I should admit that over the steadily increasing pace of years, I’ve had a grandstand view of reproduction -albeit not in the front row seats; as an obstetrician for over forty years I was involved in ‘l’accouchement‘, rather than in the arguably more exciting ‘fécondation’. Still, I came to think of reproduction as a process that necessarily involved -dare I say it- sex. Not only is this how humans reproduce, but pretty well every animal or fish shown on TV documentaries would agree that some form of fertilization is involved: sperm meets and fertilizes an egg and starts the process off.

And yet, believe it or not, sex is not the method employed for most reproduction throughout the world! The vast majority of life on Earth is microbial, and usually doesn’t do it that way: within about one tonne of soil are 1016 prokaryotic organisms [microscopic single-celled organisms with neither distinct nuclei with membranes nor other specialized organelles], and at least half of Earth’s total biomass is made up of these tiny prokaryotic microbes. So, most forms of life on this planet create living copies of themselves via asexual processes[i]. In other words, usually through binary fission -dividing in half, basically.

This leads to several problems with the way we think about the products of reproduction: if I were able to reproduce myself asexually by dividing in half, say (fission), then would that other half be simply a clone, my sibling, or my child? Would it still be me in both places, or even two new people, so I would no longer exist (as a me, at any rate)? An interesting thought experiment; it leads one to ask, for example, how we should categorize bacterial offspring once they have divided. Even our words to describe them are decidedly geared to our categories of sexual outcomes. And plants cannot escape our expectations either, despite the fact that many plant species reproduce asexually, or through a combination of sexual and asexual means.

So then, how can we define reproduction in a way that doesn’t privilege the way we are used to thinking about it?

Well, American philosopher James Griesemer suggests that reproductive processes generally share two features: first, there must be an overlap of material parts (ie, the physical material that makes up an organism) between parents and offspring; and, second, those parts must go on to develop. But no, it’s not like a photocopier: the papers it copies are not a part of the original paper fed into it, and anyway, the copies can’t develop further on their own…

And there are yet further mysteries in this asexual reproduction that require clarification: what about planting a shoot of ivy somewhere -it’s genetically identical to the parent from which it was cut, and yet it is an independent plant. Can you really call that reproduction when it was not purposefully performed by the original plant…?

Well, linguistics to the rescue (sort of…). Suppose we name these genetically identical but individual plants as ramets, and if some of them ended up growing together in a different area, obviously separated from the rest, as genets. A group of ramets, make up a genet… Uhmm, is that clear…? I think I’ll just leave it at that.

Fascinating as all of the labyrinthine kluges to explain the problems offered by non-sexual reproduction may be, I think my daughter wandered through them years ago largely unscathed. She solved the split-body problem, and fulfilled Griesemer’s criteria about material overlap and development all in one go.

She was only six or seven years old when she came home one day with a rather complex drawing she’d done at school. Normally I stuck them up on the wall of her room with sticky tape, but the ones about which she was really proud, were honoured for a time on the fridge door.

As she handed the drawing to me, she asked me a question. “Daddy, what’s a second cousin…” she hesitated for a moment to make sure she was getting it right. “…a second cousin, once taken away…?”

I was perplexed for a moment, wondering if she was asking me an unrelated question about arithmetic -Catherine often had many thoughts in her mind, all clamouring for space. I took a wild guess at what she meant. “You mean a second cousin once removed?” That didn’t really fit with handing me the drawing either, but her face immediately brightened.

“That’s it: a second cousin once removed!” She seemed pleased that I understood.

I have to admit that, despite my adult omniscience, I’ve always had trouble with the ‘second cousin’ thing, let alone the ‘once-removed’ part. I thought about it for a moment and tried to draw it on a piece of paper on the table. “Uhmm, well for me… I think my second cousin is my grand aunt’s child’s child…” Or did I get that wrong…?

“What’s a gran dant?” Catherine interrupted.

Damn. “A grand aunt, is my father’s aunt…”

She smiled, patiently, hoping I’d eventually answer her first question.

“And a second cousin, once removed is the child of that second cousin…” I hoped she didn’t press me for more details; to tell the truth, I was totally lost with the grand aunt’s child’s child. Catherine seemed satisfied, though. “But why did you ask, about the second cousin once removed, sweetheart?”

A large smile beamed across her face. “Well, I started off drawing a man, but I realized that I had to fix it, because I’d forgotten certain things. So, I added a beard like yours, and then thought he would look better if I put some pants on him -but to do that, I had to cover up his stick-legs. And one leg was longer than the other, so that didn’t look right and I had to extend a leg, and…” She looked up at me, obviously wondering if she needed to describe the blow-by-blow of the development changes.

She decided to shorten the story. “Anyway, Miss Haverton kept looking at my drawing as I added to it, and told me it was a good example of a second-cousin-once-removed drawing.” Her eyes narrowed when she said that. “How could she know that, Daddy?”

I had to think about that as well. “I think she was just using it as an expression.” Her little forehead wrinkled. “You know, like me saying ‘Holy cow’ when I’m surprised at something? I’m not really talking about a sacred cow, or anything…”

She was unfazed by the explanation. “So,” she said, trying unsuccessfully to disguise a shrug, “Are you gonna put it up on the fridge?”

[i] https://aeon.co/essays/we-need-to-stop-thinking-about-sex-when-it-comes-to-reproduction

, , , , , , , , , , ,

gozzter

, , , , , , , , , , ,

Leave a comment