What are the properties of a useful model of global systems

"A model that shows global systems, the processes that operate within each system and the ways those systems and processes interact."

Explanation:

In the global system mainly four types of models interact or co-ordinate between each other. When we take an example of the ecosystem, these four models can be predation, parasitism and herbivore. Interaction takes place in such a way that one model gets the benefits while the other one gets affected. But when talk about mutualism, both of them gets benefited from the interaction. The basis of the global system property is firstly made by the species interaction.

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.

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