  We develop a game-theoretic framework to investigate the effect of
cooperation on the energy efficiency in wireless networks. We address two
examples of network architectures, resembling ad-hoc network and network with
central infrastructure node. Most present approaches address the issue of
energy efficiency in communication networks by using complex algorithms to
enforce cooperation in the network, followed by extensive signal processing at
the network nodes. Instead, we address cooperative communication scenarios
which are governed by simple, evolutionary-like, local rules, and do not
require strategic complexity of the network nodes. The approach is motivated by
recent results in evolutionary biology which suggest that cooperation can
emerge in Nature by evolution, i. e. can be favoured by natural selection, if
certain mechanism is at work. As result, we are able to show by experiments
that cooperative behavior can indeed emerge and persist in wireless networks,
even if the behavior of the individual nodes is driven by selfish decision
making. The results from this work indicate that uncomplicated local rules,
followed by simple fitness evaluation, can promote cooperation and generate
network behavior which yields global energy efficiency in certain wireless
networks.
