Crow collects chunks of glass in a hollow tree?

Question

So I'm reading "Norwegian Wood" by Haruki Murakami and I came across this passage this line :"Like the way a crow collects chunks of glass in a hollow tree."In context:---"Don't be silly," said Midori. "You don't have to know anything to pass college entrance exams! All you need is a little intuition - and I have great intuition. 'Choose the correct answer from the following three.' I know immediately which one is right. My intuition's not as good as yours, so I have to learn systematic thinking to some extent. **Like the way a crow collects chunks of glass in a hollow tree.**"---I'm not sure what he's trying to say here. Is this some strange idiom I'm unfamiliar with? Crows tend to be intelligent creatures, however, I don't believe they are systematic.What do you guys think?Thanks!

Answer 1

No, it's not an idiom, and I'm just making an hopefully educated guess here, but yes, crows are intelligent creatures, and they use their brains for "systematic thinking," e.g. by storing chunks of glass in a hollow trees so they can return later to inspect them for bits of food for survival. So when Midori brags that he chooses multiple choice answers by his gut or intuition, the other speaker says he has to have more of a plan and a system (like the crows) because his intuition isn't good enough. Hope this helps!