, , , , , , , ,

I think not one but two hypotheses, namely the Handicap principle and the Dunning–Kruger effect, could help explain display of aggressive, silly behavior in this particular instance.

How to differentiate a fit male from one pretending to be fit?

  • The Handicap Principle doesn’t explicitly mention cheaters. As originally proposed by Amotz Zahavi, the closest it comes to cheaters is, ‘Characters which attract the other sex cannot always be separated from those which intimidate rivals of the same sex’ (1).
    • Characters which attract the other sex refers to potential reward.
    • Characters which intimidate rivals of the same sex refers to potential cost.
    • Degree of overlap between reward-yielding and costly characters is an additional issue.
  • A modification of the Handicap Principle proposed by Alan Grafen in 1991 (2) states
    • The Darwinian distinction between natural and sexual selection is ‘a distinction between selection of ordinary traits on the one hand, and the selection of signaling traits on the other‘.
    • Ordinary traits are selected for efficiency
    • OTOH, signaling traits entail waste, i.e. ‘self-inflicted costs of the signalers‘.
  • According to Zahavi- Grafen, a stable sexual signaling system should be honest and costly for the signaler yet the signals/characters themselves have no inherent meaning. How could that be?
    • Intent of the signaling, as in intent of macho behavior, is ultimately irrelevant.
    • Regardless whether macho display is authentic or pretense, what matters is what’s perceived by the receiver.
    • There are two signal receivers, one, the other sex, and two, same sex rivals.
  • The Handicap Principle does not assert that a signaling system needs to be honest and costly with greater costs for signalers of poorer quality. Rather, it asserts that any stable signaling system needs to have such properties.
    • Stability is thus the key property to assess macho behavior within the purview of the Handicap Principle.
    • The Zahavi-Grafen modification implies key cost is over time as in stability of the display, over a lifespan for an individual and across generations for a species.
    • Such a system also allows for occasional deceit.

Moving on from theory, we observe in nature that certain sexual displays, behaviors, vocalizations and other communications remain stable rituals within a species. The peacock is an obvious example.

  • We can infer from this that such displays are part of an ESS (Evolutionarily stable strategy).
  • In turn, ESS suggests that honest display gets rewarded and that cheating is costly. How so?
  • The more frequently a signal is misleading, e.g. macho display without the real strength to back it up, over time the signal receivers (the other sex and same sex rivals) would evolve to ignore such signals, and signals that are most abused would also be the ones to fall into disuse.

What to conclude about costs for human macho behavior cheaters from all this?

  • Macho behavior may not entail much energy (cost), at least for some time among (some) young men since it is frequently and abundantly on display the world over.
  • Long term, poor quality macho signals would either not yield progeny/fewer progeny, stability of macho display being the contingent factor, both at the individual level over a lifespan, and at the group level for a given culture.
  • Incompetent signal receivers could sustain poor quality signalers (even across generations).

I derive that last bit directly from the Dunning–Kruger effect. In David Dunning’s own words (4), ‘incompetent people do not recognize—scratch that, cannot recognize—just how incompetent they are, a phenomenon that has come to be known as the Dunning-Kruger effect. For poor performers to recognize their ineptitude would require them to possess the very expertise they lack‘.

  • Per the Handicap Principle, the signal receiver determines whether macho display is authentic or pretense.
  • How good are signal receivers in discriminating between genuinely fit males versus pretenders?
  • Scope for pretenders thus depends on signal receiver ability.
  • Enter Dunning-Kruger. It places the burden on the cognitive bias of the signal receiver.
  • Thus, cognitive bias of signal receivers regulates possible success of macho cheaters, i.e., those without the ‘genetic firepower’ to back up their macho display.
  • Signal receivers who habitually overrate their ability, in this case to discern genuinely fit males from pretenders, would help sustain macho displays that amount to ‘aggressive, silly behavior‘.
  • Let’s also keep in mind that there are two sets of signal receivers, one, women, and two, rival men. Incompetence on the part of both or either could help sustain macho displays that amount to ‘aggressive, silly behavior‘.

Controlled studies could distinguish the degree of contribution of each set of signal receiver, women versus rival men. Maybe also reveal interesting cultural and/or ethnic and/or geographic differences in the contribution of each set towards the success of macho displays that amount to ‘aggressive, silly behavior‘?


  1. Zahavi, Amotz. “Mate selection—a selection for a handicap.” Journal of theoretical Biology 53.1 (1975): 205-214. Page on arizona.edu
  2. Grafen, Alan. “1: Modelling in behavioural ecology.” Behavioural ecology: an evolutionary approach 3 (1991): 5-31. http://users.ox.ac.uk/~grafen/cv…
  3. Kruger, Justin, and David Dunning. “Unskilled and unaware of it: how difficulties in recognizing one’s own incompetence lead to inflated self-assessments.” Journal of personality and social psychology 77.6 (1999): 1121. Page on nottingham.ac.uk
  4. Dunning, D. (2014, November-December). We are all confident idiots. Pacific Standard, 7,46-54 Page on psmag.com