Aquatic animal locomotion

The structure of aquatic animals reflects their locomotor habits. In the case of micro-organisms, motion usually involves the action of flagella or cilia (as planar waves, oar-like beating or three-dimensional waves), through the extension of pseudopodia, or by sliding or undulating. The main distinction in the case of invertebrates is between bottom locomotion (ciliary gliding over mucus, contract-anchor-extend bottom creeping, pedal contraction waves, peristaltic contraction, and bottom walking) and swimming (hydraulic propulsion, or undulating all or parts of the body). Fish-like vertebrates of elongated form (such as eels) use a series of oscillations, passing from head to tail, to provide propulsion. In those of shorter form only the posterior half of the body flexes with such contraction waves, or in other cases only the caudal fin. Stabilization (to prevent rolling, pitching or yawing) and steering are accomplished using secondary fins. Tetrepodal vertebrates tend to use fish-like movements of their tails, rotation of flippers or wings through a figure-of-eight configuration, or alternate movement of the feet in the case of surface-swimming.

The structure of affect-oriented groups or individual personalities reflects their mode of movement through the affective and emotional contexts, by which they are supported.

The range of movements and the variety of waves in which they are coordinated.

Movement of some social actors is characterized by 'waves of emotion', which in some forms is described as 'flapping' or 'fluttering', in others as 'lashing out'. Some characteristic modes are based on 'putting out feelers' (and then shifting into the new context if there is no threat), on various forms of 'social climbing' involving making a firm contact (and using that as an anchor and then as a stepping stone from which the next contact may be reached), or on 'creeping along' over some dependable base to which adherence is assured. Another range of modes is characterized by such terms as 'drifting', 'gliding' or 'undulating through life', and also by such terms as 'wriggling' and 'slithering'; and another by strong rejection mechanisms which force the body in the opposite direction by reaction. In more controlled and directed forms, movement through society is ensured by some kind of orderly alternations between alternatives (e.g. excess and restraint, opening and closure to information, confidence and suspicion, etc) which allows the individual or groups to navigate between Seylla and Charybdis. With greater control, movement may be achieved in several dimensions between several pairs of alternatives. The ways in which such movements may be modelled by the varieties of aquatic locomotion has not been explored.

Buoyancy and the reduction in the effort required to overcome inertia. Breaking mechanisms and the necessity for continual movement in some cases. Surface swimming. Depth, pressure and characteristic forms.