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For surviving and reproduction animals had to develop the ability of communication, a mode to receive and transfer biologically significant information, at the earliest stages of evolutionary development. This feature appeared to be so beneficial that in the animal world nearly all sensory canals are used for communication. However the maximum efficiency and action at a distance are achieved using visual, auditory and olfactory sensory systems. They are normally used as a complex.
To study principles of communication insects can be used as a model. Beetles can be used for that purpose, because they possess a relatively simple nervous system including a relatively small number of elements on the one hand and because the varied behavioral reactions in them may be reduced to a complex of fixed actions on the other hand.
Communication systems using vision are based upon principles of analysis of spatial information, such as color, shape and characteristics of movements of the carrier of communicative signal. A special form of this type of communication is the ability to produce and analyze light signal. Systems using the auditory sensory canal are based upon the principle of analysis of temporal or frequency parameters of the acoustic communicative signal. Systems of communication using odors are based upon the principle of chemoreception - recognition of specific chemical substances released into the environment by individuals producing a communicative signal.
Each of these sensory canals in the communication plan has its advantages and drawbacks. For small animals, in particular beetles and other insects vision is not always efficient, because they inhabit in dense vegetation, which strongly restricts the field of vision. Apart from that under the pressure of predators many insects lead nocturnal mode of life, which also reduces efficiency of the visional sensory canal. At the same time using of sound signals considerably unmasks animals, and frequently both partners, by communicative process. This is particularly essential for females in connection with reproduction. However in the evolutionary process in some animals communicative system appeared, using the visionary sensory canal, but based upon temporal parameters of the communicative signal. This animal group acquired an ability to produce and analyze light signals.
A similar mode of coding communicative information in systems of acoustic and light communication should provide for similar principles of its decoding. Therefore both communicative systems should have much in common, but each systems has its characteristic features.
By definition of Lewis and Cover communication is the transfer of signals between organisms and parts of one organism when selection favors producing and reception of signals. In the communication process information changes and mutual adaptation of the subjects occurs. Lloyd gives examples of 24 different phenomena of communication, (subjects of which are cells, organisms and whole communities) from coordination of growth and differentiation of cells to communication of large hordes of fireflies flaring simultaneously, fish schools, etc. Common in all these cases is obligatory presence of a source and a recipient of signals in each subject of the communicative process and complex (or complexes) of actions triggered by communicative signals. A.V. Popov. Supplementing classification of Dumortier distinguishes in Orthoptera signals of danger and threat, food and sexual communicative signals. Animals respond to different types of signals by different complexes of fixed actions. Certainly differences of physical characteristics of sound and light communicative signals are quite essential, but they are very similar functionally. Thus using classification of Dumortier - Popov fireflies have nearly all signals related to sexual behavior, territorial and defense signals: search and call of males, signals of consent, refusal and post-copulative signals of females, signals of aggression, protest and even light mimicry.
Characteristic features of the above three ways of communication of beetles are considered below on separate pages of our site.
S. Landa, March, 2000