Wednesday, May 18, 2011

Spontaneous generation

Our pillbug tank (which also has slugs, and once held centipedes and soldier flies) has a new crop of newborns. Despite the dangers of sophomore handlers ("I guess I kinda accidentally dropped a rock"), our tank has as at least as many critters as we started with back in September.

They will be returning to the wilds of Bloomfield soon, and it's all good.



Almost.

Yesterday two snails emerged from the tank litter, slowly slithering their way towards a flake of fish food. We never had snails before. None.

And if my lambs are thinking, and they are truly open-minded,and if they trust that no one snuck in and put the snails in there, well, we have some evidence for spontaneous generation.

Further complicating this are the fry that hatched months ago. While most died (as expected), we have about 15 left, and they look less and less like their parents. Oh, they have gills and fins and scales and all that, but they're the wrong color and the wrong shape. (I know about color changes in goldfish--my students do not).

If I have done my job right, a few students will soon announce that we have provided evidence that spontaneous generation happens. If I've really done my job right, those same students will come up with several hypotheses as to how this occurred, and set up an experiment to replicate the results.

Heck, they'll be juniors next year, they can even run the experiment when they get back in September. In the meantime, if a few remain suspicious that maybe spontaneous generation still happens, well, at their age with their experience they should be suspicious. I encourage skepticism.

That's how science works.





No, I don't believe in spontaneous generation. I think....
I also don't believe children should accept what I (or any "experts") say at face value.

3 comments:

Mary Ann Reilly said...

This isn't only how science works, but learning involving problems and the work to solve problems. I'm hoping to oberve some students and a math and history teacher (who team teach) and see what i might learn about problem solving. The student had a task a few weeks ago to use an ancient text that contained mathematics problem and solve it. Seems like in one case the transcription of the text to English was faulty. Much learning about solving problems occurred. This is what I want to zoom in on write about: not that a problem was solved, but all those false starts, syllogistic breaths that lose breath. That's the stuff worth knowing about, like spontaneous generation and what we know, unknown, learn, and unlearn.

Kathryn J said...

Would you please 'splain to me about the goldfish? I'm curious.

doyle said...

Dear Mary Ann,

You cannot know how much your words matter here.

Yes, it's the false starts and the syllogisms that matter--that's where our cortex separates us from the dolphins, the apes, and (hey, they're really bright!) the grackles.

I have (belatedly) started focusing on the unlearning. It's a critical piece, and it requires deep observation.

Not sure I can make a place for it under the current education stressors, but I'm going to try.



Dear Kathryn,

I moved my goldfish around this year. I put them into a big lovely tank that had been percolating much of the year, and they proceeded to devour the original occupants, so I moved them back into a tank small enough that PETA could justifiably attack.

A week or two later, tiny fry, gazillions of them, roosted in the big tank.

Now that they are bigger, they look less and less like goldfish.

We'll see, though. I have one student who has been categorically assessing the young'uns, and he's convinced they are indeed goldfish.