Using People as Evidence

So while we all agreed that the mold was consuming the dead fruit in some of our jars (the mold was obviously getting larger while the strawberries were getting smaller), we still weren't entirely convinced about gathering enough concrete evidence about using weight as proof.

So we wondered, "What else consumes dead stuff? That we could weigh?"

US!

So with some bananas in hand and a scale available, we did some eating and weighing...

Our results were pretty interesting and not what we expected.  Out of the ten students weighed between the two classes, only three actually gained the weight of the banana that they ate. We had a pretty good discussion about why this was the case; most likely due to a faulty scale.  We also discussed the importance of a large sample size, because if we had only taken the measurements of say one student, and that student happened to be the one who lost weight, we wouldn't have any data to support our claim that eating make you gain weight and that the weight of the thing being eaten goes down.

From this we've realized a lot...and that there's three big ideas that have surfaced.

1. The living organism that eats gets bigger as it consumes dead stuff.  It's weight increases and the amount of matter in it gets larger.
2.  The dead organism that is being eaten gets smaller and its weight decreases.  It's matter goes into the organism that is consuming it.
3.  Altogether, the amount of matter stays the same in the system...it just gets rearranged.  For example, the dead badger's matter goes into the larger, the dead plants matter goes into the worm or the mold, and the eggs' weight a female fly lays gets larger as she lays them.  The total matter of all these things stays constant, and just moves from organism to organism.

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