Collective animal behavior

Studying the principles of collective animal behavior has relevance to human engineering problems through the philosophy of biomimetics.

For example, Nicolis and Prigogine (1977)[2] employed the use of non-linear thermodynamics to help explain similarities between collective systems at different scales.

These proposed functions may be grouped into the four following categories: social and genetic, anti-predator, enhanced foraging, and increased locomotion efficiency.

[7] Fish schools have also been proposed to serve a reproductive function since they provide increased access to potential mates.

This theory states that as the size of the group increases, the task of scanning the environment for predators can be spread out over many individuals.

Not only does this mass collaboration presumably provide a higher level of vigilance, it could also allow more time for individual feeding.

Hamilton, for instance, proposed that the aggregation of animals was due to a "selfish" avoidance of a predator and was thus a form of cover-seeking.

[20] In the detection component of the theory, it was suggested that potential prey might benefit by living together since a predator is less likely to chance upon a single group than a scattered distribution.

[22] In this study, the time it took for groups of minnows and goldfish to find a patch of food was quantified.

[23] This theory states that groups of animals moving in a fluid environment may save energy when swimming or flying together, much in the way that bicyclists may draft one another in a peloton.

[27] Larger groups of animals tend to harbour an increased number of pathogens and are at a higher risk of epidemics.

[28] This is particularly due to the large amount of waste material produced by larger groups, allowing for a favourable environment for pathogens to thrive.

Female bottle-nose dolphins with similar home ranges tend to have varied foraging habits in an effort to reduce and negate the intraspecific competition of resources.

[30] Benefits of group living on defence from predators is very evident in nature, however in locations of high resource competition poses an effect on the mortality of certain individuals.

This can be seen in species of shoaling fish, where the initial aggregation of individuals to a group initially allowed for the protection from predators, however the limiting resources available changes over time, and mortality rates of these fish begin to increase,[31] showing that resource competition is an important regulator of reef fish groups after the initial benefits of refuge grouping and predatory protection.

Interesting contrasts to the benefit of increased group size on foraging efficiency can be seen in nature particularly due to intraspecific interactions.

A study conducted on the Alaskan moose shows that with increasing group size, there is a decrease in foraging efficiency.

A large group of animals may suffer larger levels of stress arising from intraspecific food competition.

In contrast, smaller groups may have increased stress levels arising from the lack of adequate defense from predators as well as a reduced foraging efficiency.

This capability requires the use of multiple cameras trained on the same volume in space, a technique known as stereophotogrammetry.

When hundreds or thousands of animals occupy the study volume, it becomes difficult to identify each individual.

[41] Pair Distribution Function: This parameter is usually used in physics to characterize the degree of spatial order in a system of particles.

Cavagna et al. found that flocks of starlings exhibited more structure than a gas but less than a liquid.

While the role of a leading matriarch in an elephant herd is well known, studies have shown that some animal species use a consensus approach in their collective decision-making process.

[49] Consensus decision-making, a form of collective intelligence, thus effectively uses information from multiple sources to generally reach the correct conclusion.

Some simulations of collective decision-making use the Condorcet method to model the way groups of animals come to consensus.