Later, this behaviour appeared to be an artifact of intrusive laboratory observation. Whether the behaviour in the field is natural, or also the result of distractions caused by the human observer, remains controversial. Mantises are highly visual organisms, and notice any disturbance occurring in the laboratory or field such as bright lights or moving scientists. Research by Liske and Davis (1987) and others found (e.g. using video recorders in vacant rooms) that Chinese mantises that had been fed ad libitum (so that they were not starving) actually displayed elaborate courtship behavior when left undisturbed. The male engages the female in courtship dance, to change her interest from feeding to mating.
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