Technological approach to insect anatomy and evolution
Zoological Museum of Lomonosov Moscow State University
ul. Вol'shaya Nikitskaya, 6, 125009 Moscow, Russia
e-mail: elfedoseeva@rambler.ru
Principal disadvantage of most of the recent approaches to reconstructions of the insect evolution is due to comparison of the species by formal character sets with unknown functional relations. This leads to ignorance of the systemic nature of differences caused by integrity of the living beings. Under consideration is an alternative approach to description of the insect body construction based on A.M. Ugolev's concept of natural technologies. According to it, a morphological structure is a device designed for fulfilment of certain tasks. Therefore, a structure's characteristics have to fulfill the tasks' conditions.
This approach is considered as applied to the systems of muscles and sclerits providing for vitally significant functions such as feeding, locomotion, communication, protection, etc. Any such skeletal-muscle system is arranged hierarchically. A muscle together with its supporting sclerits is considered as a skeletal-muscle complex (SMC) capable for a mechanic action. Such SMCs, after respective muscle activations, are integrated into blocks responsible for the elementary tasks of the lower level of the motoric process. Each block can be formed by both a particular active SMC and by a group of biomechanical elements. Each block is considered mono-functional, unlike multifunctional SMCs, as it accomplishes a particular elementary task, namely displacement of a particular sclerit. Various compositions of blocks form subsystems corresponding to the higher level tasks.
An aggregation of SMCs constituting the blocks accomplishing elementary actions is defined as the technological system designed for the motoric process. Organismic SMCs being compositionally constant, control over their activity serves as a mechanism of combining biomechanical elements. This mechanism is responsible for creation of a wide spectrum of motoric systems. SMCs' composition is changed in the course of evolution which is reflected into motoric parameters. Thus, certain characteristics of the SMCs and their compositions are correlated with certain functional parameters. Therefore, both the subsystems and the entire motoric system as the functioning devices can be characterized in two respects, by their composition and by functional parameters of respective type and rank. The above consideration serves as a basis for the block-scheme of description of the insect motoric systems similar to the relational database design. Three types of objects are to be incorporated in such a block-scheme. One type includes functional items ranging from elementary actions to motoric processes and their effects. Another type includes morphological items ranging from SMCs to the body parts and to the body as a whole. The third type includes technological items which are blocks, subsystems and systems. All three types reflect different aspects of description of the entire subject domain defined as the technology of the vitally significant effects. Descriptions of the objects of the same type and rank are standardized by the same characteristics and are arranged in the standard tables. Relations between the table descriptions reflect hierarchical interrelations of the objects of the same type, as well as interrelations defined by the role of morphological objects in the fulfilment of particular motoric tasks. Such an approach to the description design makes it possible to define the spectrum of effects dependent on the general structural parameters.
Its application to comparative analysis of the abdomen in the ants and other Aculeata allowed to recognized three motoric systems which interactions define metasomal constructive diversity in Formicidae. These include the stigmal valves system and two segmentary movements systems, compressions and bendings. Principal type of the ant metasoma are recognized which are compressional, tubulational-compressional, and tubulational. These types are closely correlated with such biological functions as liquid food transportation behaviour, protective behaviour, types of food storage, types of within-nest temperature regulation. Increase of the intersegmental joints in the metasoma is shown to be correlated with the actions requesting both flexibility and rigidity of its segments (balancing, inoculation, movements in the soil). But simultaneously, reduction of the abdomen capability to compression and stretching leads to reduction of breathing actions needed for the metabolism intensification. It served as a fundamental precondition for the formicid ancestors to shift from the flight to less energy consuming walking locomotion that lead eventually to the existing metasome diversity.
The principles of systemic analysis contained in the above technological approach eliminate the gap between investigations in morphology, physiology and ecology of insects. The description procedure does not substitute for the morphofunctional analysis but allows structuring diverse information and providing for adequacy of comparisons of organisms. The approach is supposed to be applicable to the systems of any levels of complexity up to the supra-organismal ones. It makes such an approach promising in explorations of evolution of coadaptions, of social systems and of ecological systems.
