Chapter 1, The Reptilian Spectacle - UWSpace - University of ...

At 30 minutes into the experiment, a potential threat to the snake was simulated by having the
white-coated experimenter step out from behind the curtain for 8 minutes, and perform routine
laboratory activities within 1.5 meters of the boxed snake. It should be noted that in the case of these
captive coachwhips, a white-coated human was deemed an effective threatening stimulus as evidenced
by their exhibition of vigilance behaviour and occasional attempt to hide or flee when their terraria
were approached.
After the 8 minutes, the experimenter returned behind the curtain. The simulated threat was
repeated 16 minutes later, when the experimenter again stepped out from behind the curtain for 8
minutes. The experiment was concluded 8 minutes after cessation of the second simulated threat. The
timeline of a trial is illustrated in Figure 2-5. The decision to present the threat for 8 minutes and do
comparisons on blocks of 8 minutes was based on preliminary observations that the spectacle blood
flow could cease for up to approximately this amount of time under the pilot experimental conditions.
Figure 2-5. Timeline of an experimental trial. Each trial lasted for 70 minutes, with the subject
remaining undisturbed for the first 30 minutes. This was followed by 8 minutes during which a visual
threat was presented (Threat 1), after which it was removed to leave the subject undisturbed for 16
minutes before the threat was presented a second time for 8 minutes (Threat 2). The trial ended after
the subject was left undisturbed for another 8 minutes. b1, d1, a1, b2, d2, a2 refer to the 8 minute
blocks before, during and after the first and second threats from which statistical comparisons were
made.
30 minutes undisturbed Threat 1 undisturbed Threat 2 undisturbed
b1 d1 a1 b2 d2 a2
0 10 20 30 40 50 60 70
Time (minutes)
Each of the three snakes were tested 7 times on as many days, ensuring that they were only
tested once per day. Although observations were made during the snakes’ moulting phase, experiments
were not conducted during this time due to clouding of the eye, changes in behaviour, and changes in
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