7 wrens, sets of sets
I was thinking about sets of sets when I came across this set of similar wrens, discussing the collections of identifying marks that make up a distinguishable bird species.
The same site has a lovely little discussion of preparing the mind to see birds.
Experts say that when we lose something, before we begin our search to find the lost thing we should picture the object in our minds. This kind of “visualization” causes the brain to do something wonderful. On the one hand, it appears to filter out many unnecessary sightings but, on the other, if something even remotely resembling the lost object comes into view, the mind seems to “jump” at it.
Power of pattern matching.