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missed Darwinian opportunity
Tuesday, July 17 2012
Eleanor treed a Woodchuck this morning, and the poor thing stayed in the tree (a large White Pine) for a couple hours before climbing down. Had he/she stayed up there several more hours, I would have helped him/her down like I would've a cat. While he/she was there, I took a couple pictures.
This morning while washing the dishes, I listened to the latest Radiolab podcast, this one being the remarkable story of a guy who was irradiated twice by bombs exploding in a war that had gone nuclear: once in Hiroshima and once in Nagasaki. I loved the story until it got to the improbable part where our poor twice-irradiated hero fathers two perfectly-healthy children. The question then is: how is this possible? Various reasons are advanced, including the existence of gene repair mechanisms, but the most important one is overlooked. This is unfortunate because it is the much-misunderstood primary mechanism in our modern understanding of biology: survival of the fittest. Survival of the fittest works at lots of different scales and can help explain everything from speciation to bacterial resistance to antibiotics. In this case it easily explains why horribly-deformed babies aren't routinely produced by fathers who were irradiated before those babies' conception. Almost all serious genetic problems present in sperm results in a failed pregnancy if conception even happens. Development in utero is one of the most arduous shake down cruises a genome ever experiences. If a set of genes can boot up into a human, chances are they were mostly okay. Obviously, there are exceptions and babies are occasionally born with serious genetic problems. But far more babies with such problems die before ever being born. Radiolab is full of teachable moments, and this was a great opportunity to lay out a practical example of the consequences of Darwin's mechanism. (I should mention, by the way, that irradiation of a baby while it is in utero often does result in serious deformities, since such radiation will tend to cause the most damage to cell lines that are growing fastest; indeed, according to this same Radiolab, many of the babies exposed to in-utero radiation at Hiroshima and Nagasaki were born with microcephaly.)
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Earlier this summer Gretchen had bought a pot of flowers to hang from the roof near our front door. They were, I would eventually discover, Thunbergia alata, and they'd been doing well before we left for the Pacific Northwest. But evidently Sarah had forgotten to water them because they were nearly dead when we returned. Amazingly, though, with a few days of watering they were flowering again, first with one flower and today five more. It wants to flower prolifically, but the hanging pot must be watered every day.
After an hour-long co-ordinating phone conversation with some colleagues down in the city, I felt like I'd earned myself enough time to undertake a tricky procedure in the greenhouse upstairs. I wanted to install the first of the four window panes I'd retrieved from the coast of Connecticut several weeks ago. What would make this tricky was that I wouldn't be installing any sort of casement for this pane (or any of the others); I'd be attaching casement hinges to the panes and then attaching the hinges to the inside of the large south-facing rough opening (which I'd tried to make as square, level, and accurate as possible). Initially I'd been concerned that it would be impossible to safely hold the pane in place while securing the hinges within opening, since exposing the hinges enough to install fasteners requires that the window be manually (and awkwardly) cantilevered out into space, which at the greenhouse is a particularly delicate zone, since anything falling from there will crash into the south-facing glass of the greenhouse downstairs. But it actually turned out to be a fairly easy install. This was because the hinges don't actually have to be fully-open to attach them to the opening. It's also possible to initially secure a pane reasonably well with just one screw going into the top hinge. I should note that the south-facing opening is about three eighths of an inch too tall for the window panes, but I didn't use any shims for the hinges. I just attached them with long screws that protrude by the amount necessary for comfort. Later I can add some sort of spacers between the opening and the hinges as I finish the post-hanging casement details (which will involve a lot of fussy work with small pieces of precisely-cut lumber).
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