What does the reliance on purely woven structure suggest about the evolutionary pressures on weaver birds?

An evolutionary pressure favoring dexterity and material science over material strength

The methodology employed by weavers—relying almost exclusively on the friction, tension, and precise looping of pliable materials to create interlocking structures—indicates a specific evolutionary trajectory. This suggests that, within their habitats where flexible grasses are consistently available, there was a strong selective advantage for superior dexterity and an innate understanding of material science (like tensile strength and knotting). This emphasis on intricate structural technique superseded the need to rely on the adhesive properties of mud or the sheer rigidity of heavier materials.