House Sparrow

Male house sparrows wear their status literally - in black throat bibs that predict dominance, territory quality, and mating success. Bib size signals competitive ability, but here's what makes it fascinating: the signal itself is cheap to produce. Any male can grow melanin feathers. What keeps the system honest isn't production cost - it's social enforcement. Males displaying oversized bibs relative to their actual fighting ability get attacked aggressively by others who 'call their bluff.' The sparrow community polices its own status signals.

This is conventional signaling: a badge system maintained not by biological constraints but by social consequences. Unlike costly signals (peacock tails that genuinely handicap poor-quality males), conventional signals work through collective agreement and enforcement. It's the biological equivalent of a dress code - arbitrary in content, powerful in consequence, enforced through peer monitoring.

For business, house sparrows reveal how status signals get policed in competitive environments. Titles, credentials, and brand positioning function as badges of status - cheap to acquire but dangerous to fake if your peers can test your claims. The sparrow's lesson: signals work when the community has both incentive and ability to punish deception. In markets where customers can 'call your bluff' through trial, reviews, or comparison, inflated signaling becomes actively harmful.