Apart from these models, some models using only attractive-repulsive forces 24, 25, 26 or using Morse potential and Leonard-James potential alongside alignment conditions 27 have also been proposed. The Cucker-Smale model has also undergone some modifications by addition of noise 22 and incorporation of repelling force 23. While the features of the Vicsek model and the Boids model can be used for only collective behaviour in organisms 19, 20, the Cucker-Smale model is highly diverse, finding use in finance and other dissimilar fields 21. Some examples of this can be escape and hunting accelerations in the Boids model and noise in the Vicsek model. Numerous additions and enhancements have also been done on these models to make them more veritable 14, 15, 16, 17, 18. The most popular among them are the Vicsek model 11, Boids Flocking Model 12 and the more recent Cucker-Smale Model 13. They spoke of eight evasive actions undertaken by the sand-eels, which was later expanded to twelve by Pitcher & Magurran 10, and compared the probabilities of selection of such actions with variation in surrounding conditions.Īs for the numerical and analytical works, a number of models have been developed, where the organisms are considered to be self-propelling particles following certain interaction protocol. The different types of manoeuvres conducted by prey aggregates were scrutinized and classified by Pitcher & Wyche 9. This leadership concept was extended by Rands et al. Later, Radakov 1 coined the terms “waves of agitation” and “streams of agitation”, which were used to describe how Breder’s leader fish was able to transmit information to the rest of the shoal. Breder 5 in his widely acclaimed book on collective motion in fish wrote of a possible concept of a leader fish, which has more enterprise or vision than the other fish in the shoal and asserted that the behaviour of this leader fish decides the behaviour of the shoal. The physics behind this behaviour, however, is highly debatable with research ranging from experimental observations on a flock of birds or a shoal of fish to numerical work under a multitude of conditions 1, 2, 3, 4. Such behaviour can be observed all around in nature from human beings to fish to even micro-organisms. This adversity might have been a possible reason for organisms to develop co-ordination, which has been termed as collective behaviour or collective consciousness. One such scenario is that of the presence of a predating species in the vicinity. Similar content being viewed by othersĭarwin’s theory of evolution speaks of adaptability of organisms to adverse conditions in order to ensure survival. The role of these factors in affecting survival rate of prey is given due coverage. The rate of information transfer is studied as a function of co-ordination and the size of the influence zone and the source strength is studied as a function of escape acceleration activated on the agitated prey. The success of any escape manoeuvre is dependent on the rate of information transfer and the strength of the agitation at the source of the manoeuvre. This study strives to understand the penalty on the collective motion due to the restraints employed by the rigid walls of the confinement and the predator’s hunting tactics. The regimes observed at differing levels of co-ordination segregated by quantification of global order parameter are found to be in agreement with the extant literature. A novel individual-based combination of Vicsek model and Boids flocking model is used for defining the self-propelling action and inter-agent interactions. The state of motility when alive and passivity on death has been accounted for. Both the predator agent and prey agents are considered to be self-propelled particles moving in a viscous fluid. One such hunter-hunted pair is considered in this context and coordinated escape manoeuvres in response to predation is studied in case of a rarely examined confined system. In nature exists a properly defined food chain- an order of hunting and getting hunted.
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