Weavers collect pieces of palm fronds, grass and anything else in that line with which they build and line their nest.
Considering they only have a beak to build with, the nests are something which we cannot duplicate using two hands!! They are strong and can withstand very harsh storms.
Hanging Flies belong to the Mecoptera family and are sometimes called Scorpion Flies. Being predatory, the male must mate with caution or be eaten. LOL!! He distracts the female by offering her something to eat while he goes about his mating business.