Table 1.

Comparison of analogies for subcellular biological networks

	Biological network	Wiring diagram	Eurovision song contest
System	Living organism	Electronic device (e.g. radio)	Music competition
Elements	Biological molecules	Electronic components	Countries' representatives
Nature of elements	Complex chemical entities with evolutionary histories	Minimal elements designed to perform simple tasks	Complex decision-making units with historical continuity
Clearly defined element functions	Performing biological functions (e.g. as described in GO terms)	Component specifications	Performing songs
Other element features involved in network function	Genetic location	None	Geographical proximity
	Transcriptional, translational, post-translational and degradation control		Politics
	More or less specific PPIs		Cultural history
	Other known and unknown relationships		Other unknown relationships
Performance measure	Inclusive fitness of an individual within a population	Performance of one or more pre-defined functions	International TV audience figures
Evolutionary step	DNA mutation	Addition or removal of connection or component	Change in individual voting behaviour