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Are there mathematical models that describe warfare tactics between competing clans of monkeys, perhaps similar to the predator-prey dynamics modeled by the Lotka–Volterra equations?

I am particularly interested in the formation of opposing lines and the subsequent dynamics observed in this video clip.

Has this type of behavior been studied mathematically before?

MJD
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rehband
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    This might be more of a question for biologists rather than mathematicians. – Arthur Aug 08 '24 at 10:29
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    @Arthur -- mathematics is an ancillary discipline to help other exact sciences to desribe observations as accurately as possible. It's no harm if mathematicians demonstrate their practical benefits at times. – m-stgt Aug 08 '24 at 13:23
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    I understood Arthur to be suggesting only that the biologists would be more likely to know the answer, not that the question was inappropriate for this site. – MJD Aug 08 '24 at 14:26
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    @MJD Yes. If I were looking for someone who knows the answer to this, I would personally look for a primatologist who happens to know a little modelling, rather than a mathematician who happens to know about the social structures of primates. I'm not saying it's wrong to go this way, but I think success is more likely the other way. – Arthur Aug 08 '24 at 16:07
  • There are many general models of dynamic game theories, pattern formation, co-evolution, etc. in mathematical and computational biology. But I don't know if anyone has applied those models to describe warfare between clans of monkeys. But search those key words, you may find some applications close enough (different species) to what you've been looking for. – Paichu Aug 08 '24 at 16:30
  • @Arthur I appreciate the advice -- I did actually initially post this question on the biology stackexchange but my question was closed there. – rehband Aug 08 '24 at 18:41
  • @Paichu Could you point me more specifically to some of those applications that may be close enough? – rehband Aug 08 '24 at 18:42
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    Watching the video that you shared, I think the dynamics that you're looking for are a bit more transient. Not sure if there is anything on it. Mathematical studies tend to look at species distribution over a long period of time. A quick search on Google Scholar yields this: https://doi.org/10.1007/s11538-021-00886-4. This is a study of pattern formation of three generic species competing within the same space. It's more mathematical than biological, so I'm not sure if it is helpful. – Paichu Aug 08 '24 at 18:54
  • I did Google search (for "mathematical models" "primate" "conflict") just now and found some things that are at least conceivably related to what you want, such as https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3160838/ . You might do that also and then take a look at the bibliographies of Google's suggestions. – MJD Aug 08 '24 at 22:32

1 Answers1

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Yes, mathematical models have been developed to study animal conflict and territorial behaviors.

Smith and Price did an interesting work in 1973 where they applied game theory to study animal conflicts, particularly through the development of the Hawk-Dove Game. This model explains the evolution of aggressive and non-aggressive behaviors among animals of the same species competing for resources. This framework considers two strategies: the "hawk" strategy, where an individual always fights for a resource, and the "dove" strategy, where an individual avoids fighting and retreats if confronted.

Let the value of the resource be denoted by ( V > 0 ), and the cost of injury in a fight by ( C > 0 ). When two hawks meet, they fight, and each has a 50% probability of winning, resulting in an expected payoff of $ \frac{1}{2}(V - C) $. If a hawk meets a dove, the hawk wins the resource outright, gaining a payoff of ( V ), while the dove retreats without incurring any cost, receiving a payoff of ( 0 ). Finally, when two doves meet, they share the resource without fighting, resulting in an expected payoff of $\frac{V}{2}$ for each.

\begin{array}{c|c|c} & \text{Hawk} & \text{Dove} \\ \hline \text{Hawk} & \frac{1}{2}(V - C) & V \\ \text{Dove} & 0 & \frac{V}{2} \end{array}

The dynamics of the population can be modeled by considering the proportion of hawks, $x_n $ in generation n , and the proportion of doves $ 1 - x_n $. The average reproductive success of hawks and doves, $R_1(n)$ and $ R_2(n) $, respectively, is determined by the expected payoffs from encounters. The proportion of hawks in the next generation is given by:

$ x_{n+1} = \frac{x_n R_1(n)}{R(n)}$

where $R(n)$ is the average reproductive success of the entire population. The model predicts three possible steady states: a population entirely composed of hawks ( x = 1 ), a population entirely composed of doves ( x = 0 ), or a mixed population with a stable proportion of hawks and doves, $x^* = \frac{V}{C} $, provided ( V < C ).

So, in game-theoretical Models, groups choose tactics (e.g., attack, defend, retreat) based on expected payoffs.

As seen in your video, monkeys align into opposing formations, mathematical models for swarm/crowd dynamics can be adapted to include aggression (member of opposing groups) and cohesion forces (to be member of the same group).

References

  1. https://www.nature.com/scitable/knowledge/library/primates-in-communities-the-ecology-of-competitive-59119961/
  2. Maynard Smith, J., Price, G.R.: The logic of animal conflict. Nature 246, 15–18 (1973)
  3. N. Jia, Z. Yang, T. Liao, Y. Dou and K. Yang, "A System Dynamics Model for Analyzing Swarming UAVs Air Combat System,"
  4. Coalition formation: A game-theoretic analysis