  We show that a network of non-identical nodes, with excitable dynamics,
pulse-coupled, with coupling delays depending on the Euclidean distance between
nodes, is able to adapt the topology of its connections to obtain spike
frequency synchronization. The adapted network exhibits remarkable properties:
sparse, anti-cluster, necessary presence of a minimum of inhibitory nodes,
predominance of connections from inhibitory nodes over those from excitatory
nodes and finally spontaneous spatial structuring of the inhibitory
projections: the furthest the most intense.
