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270 S. Shabala<br />

18.3.2.2<br />

Spatial Organisation<br />

Oscillations may provide synchronisation of events widely separated in<br />

space between different cells, or between subcellular compartments (Lloyd<br />

and Stupfel 1991). At the whole-plant level, frequency-coded signals are<br />

believed to play an important role in communication between the different<br />

organs and tissues (Wagner et al. 1998). Oscillations may also provide<br />

a specification of positional information during morphogenetical development<br />

(Hejnowicz 1975; Lloyd and Stupfel 1991).<br />

18.3.2.3<br />

Prediction of Repetitive Events<br />

Oscillatorysystemsareabletorespondrapidlytoinputsreceivedfromtheir<br />

environmental surroundings (Lloyd and Stupfel 1991). A plant’s ability to<br />

utilise sunflecks is one such example (Pearcy 1990). Also consistent with<br />

this idea, plant adaptation to a changing environment means resetting to<br />

a new circadian and/or ultradian rhythm (Erdei et al. 1998).<br />

18.3.2.4<br />

Efficiency<br />

Theoretical models show that the energetic efficiency of oscillatory processes<br />

may be greater in the oscillatory mode than when steady-state behaviour<br />

prevails (Termonia and Ross 1982; Richter and Ross 1981), providing<br />

an evolutionary advantage over those organisms incapable of anything<br />

other than steady-state behaviour. Another advantage of an oscillatory<br />

strategy is that oscillations may enhance sensitivity to weak external stimuli<br />

(Dolmetsch et al. 1998).<br />

18.3.2.5<br />

Precision of Control<br />

It is widely accepted that oscillations may act as a filter to discriminate true<br />

signals from environmental noise (Tsien and Tsien 1990; Lloyd and Stupfel<br />

1991). Theoretical findings by Rapp et al. (1981) suggest that, being more<br />

robust to environmental perturbations, an oscillatory strategy provides<br />

significant functional advantages for living cells.<br />

18.3.3<br />

Deterministic Chaos and “Strange” Behaviour<br />

Theoretical studies show that non-linear systems will possess complex dynamics<br />

leading to “strange” behaviour such as bifurcation and chaos (com-

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