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Figure 2.4.
Results of computer simulations described in the text showing global
system behavior. For each sampling event of the simulation, the proportion of
individual elements that are “on” is shown (Panels A and B) or the residual
stimulus is shown (Panels C and D). Panel A: h e distribution of thresholds
among elements is random between 1 and 100, with an average of 50.5. Initially,
the stimulus level was constant at 50 and was decremented 1 unit when an
element turned on. h is model demonstrates properties of homeostasis resulting
from negative feedback regulating the stimulus level at a point determined by the
average of the threshold distribution used, such as occurs, perhaps, with honey
bee thermal regulation of the nest. Panel B: h e distribution of thresholds among
elements is random between 1 and 100, with an average of 50.5. Initially, the
stimulus level was constant at 50 and was decremented 1 unit when an element
turned on. h e stimulus level was sampled by all elements simultaneously,
resulting in mass-action responses of all elements with thresholds below the
initial stimulus level turning on and of simultaneously. h is action is similar to
alarm responses in honey bee colonies. Panel C: h e distribution of thresholds
among elements is random between 1 and 100, with an average of 50.5. Initially,
the stimulus level was constant at 50 and was decremented 1 unit when an
element turned on. h e stimulus level was increased 20 units at er every 500
samples of the network. h e network displayed system plasticity and resilience in
response to increases and decreases in stimuli such as we observe in undertaking
behavior (see Section 3.1 for discussion of plasticity and resilience). Panel D: h e
distribution of thresholds among elements is i xed at the average value of the
simulations, 50.5. All elements operate with same threshold. Initially, the
stimulus level was constant at 50 and was decremented 1 unit when an element
turned on. h e stimulus level was increased by 20 units at er every 500 samples
of the network. h is network demonstrated a pronounced division of labor
among the elements, with some frozen on while others were frozen of . h is
behavior might be observed when a i nite number of worker honey bees respond
to an increasingly large stimulus. From Page and Mitchell 1998,
Apidologie
29(1- 2): 171- 190, Fig. 3, http:// dx .doi .org /10 .1051 /apido:19980110 .
