The Descent of Man: Black Friday and Fisherian runaway selection

Occasionally, the disparate thoughts rattling around my head align to form a coherent narrative. This happened to occur this weekend at the Bristol Museum. The weather was miserable, so like many parents we were looking for something to keep the kids occupied for a few hours. We’d been stuck in Black Friday sales traffic coming into Bristol, and I was idly pondering the socio-economic implications of this cultural phenomenon as we browsed the geology section, when we came across a huge skeleton of an Irish Elk.

Irish Elk skeleton at the Bristol Museum

The sad tale of the Irish Elk is a famous example of Fisherian runaway selection, a concept rooted in Darwinian theory. The elk’s conspicuously large antlers functioned as a form of status signalling. Males with big antlers were favoured by females, and over generations this preference, combined with extreme competition for mates, manifested in enormous antlers. Yet this ostentatious display ultimately carried a heavy cost. Huge antlers required vast amounts of energy to grow and made moving through forests more cumbersome. As climates shifted and resources became scarcer, these burdens grew unsustainable. The very trait that once broadcast status and success may have hastened the species’ extinction.

Humans, too, are susceptible to a form of runaway selection. Social competition and a culture of status signalling can drive people to covet eye-catching markers of success. A Rolex, for example, is no more accurate than a cheap battery watch and rarely increases genuine happiness, yet it broadcasts wealth and prestige. Black Friday shopping exemplifies this dynamic; a feeding frenzy of self-defeating consumerism, where people rush to acquire goods they neither need nor truly value. Spending on items that do little for well-being can even undermine Darwinian ‘fitness,’ straining finances and potentially jeopardising long-term security. Just as with the Irish Elk, characteristics or behaviours that signal status can sometimes escalate beyond practicality, at considerable cost.

So, before embarking on a credit card-fuelled spending spree this week, spare a thought for the Irish Elk. Its fate reminds us that chasing status - whether through flashy purchases or the parading of enormous body parts - could leave you regretting the consequences. Incidentally, the Bristol Museum is free to enter and well worth a visit on a wet winter weekend.