Abstract
I numerically studied the population changes in three spicies ecosystem on which the spicies diffuse given network. I introduced the randomness of the network using the exchange of randomly selected edges with a given probability. The network constructed by such a process is called the small world. In case of relatively large degree of connection, conelations between the most distant pairs increase with an increase of the probability. This fact shows that the ecosystems with the small world networks have a tendncy to syncronize the whole system.
