“…They are designed on the basis of cognitive behaviour of certain biologically inspired entity e.g., ant, honeybee, firefly, frog, fish, cat, dolphin, etc. The studies that has used swarm intelligence linking with energy efficiency are as follows: Gray-wolf optimization (Arafat et al [91]), Bat algorithm (Cao et al [92]), flocking control scheme using swarm intelligence (Dai et al [93]), firefly mating optimization (Faheem et al [94]), fish algorithm with k-means clustering (Feng et al [95]), multi-swarm optimization (Hasan et al [96]), Harris' Hawk optimization (Houssein et al [97]), particle swarm optimization (Mukherjee et al [98]), Chicken swarm optimization (Osamy et al [99]), reinforcement learning with swarm intelligence (Wei et al [100]). However, different approaches have their own structure of working which is implemented on WSN on different targets of optimization towards energy efficiency.…”