A botany lesson, sparrow style: those twiglets on the stag-horn
sumac: they're not branches, as they might appear
to be; they're the stems of the compound leaves of this garden shrub.
It's turning colour and the leaves are falling one by one, so these
sparrows are chancing it when they perch there in the morning sun,
especially as all four of them squeeze together, chatting and jostling
with each other, on the same slender twiglet.
Down they all go, like a sight-gag in a Looney Tunes cartoon.