Weaver building nest (Mc Pool)

Weaver building nest (Mc Pool)

Observation - Weaver building nest (Mc Pool) - Southern Africa. Description: I noted that the chamber area of the nests in the area where all built with large holes at the base. Why? Assist in climate control in nests?

I noted that the chamber area of the nests in the area where all built with large holes at the base. Why? Assist in climate control in nests?