Why doesn’t bird receive shock when it sits on an electrical wire?

A bird sitting on a single wire doesn’t get shock.

The current lines passing over the streets consists of four wires, 3 phase wires and one neutral wire. For a body to receive shock, electrons must flow through it with a source of high potential to that of low potential. If one touches only a phase wire with both hands, there would not be any difference in potential and hence no possibility of getting shock.

However, if one touches one phase wire with one hand and another phase wire with another hand or neutral wire with another hand by staying in air, electricity will flow from one wire to another through this body because of potential difference.

Also if one touches a wire with his hands and puts his legs on ground then also he acts as a medium for the flow of electrons and receives shock.

Similarly, if a bird sits only on one wire,it does not get shock. If it puts one leg on one wire and another leg on different wire, then it receives shock.