The last time I went to the farm with my camera, Neil showed us some flats of squash seedlings that some of the members had worked on. I don't know if it was the sheer number of them or what, but I noticed something about the leaves that I've never noticed before:
The leaves on the little sprouts aren't all the same shape. Like a dummy, I said something about it, and Neil explained about how the first two leaves are some kind of special ones that emerge before the plant's true leaves. Of course I forgot everything he said by now, but I looked it up! They're called cotyledons, and they have something to do with how the seed is fed, etc. (Click the link to read more.) I've probably seen this a hundred times, but it never dawned on me that those first leaves are DIFFERENT! Wow!