“A couple arrive at a fancy restaurant and they’re offered the wine list. This establishment only has two bottles on offer, one costing £5 and the other costing £25. The second bottle seems too expensive and the diners select the cheaper one. The next week, they return. Now, there’s a third bottle on the list but it’s a vintage, priced at a staggering £1,000. Suddenly, the £25 bottle doesn’t seem all that expensive, and this time, the diners choose it instead.
Businesses use this tactic all the time – an extremely expensive option is used to make mid-range ones suddenly seem like attractive buys. The strategy only works because humans like to compare our options, rather than paying attention to their absolute values. In the wine example, the existence of the third bottle shouldn’t matter – the £25 option costs the same amount either way, but in one scenario it looks like a rip-off and in another, it looks like a steal. The simple fact is that to us, a thing’s value depends on the things around it. Economists often refer to this as “irrational”.
But if that’s the case, we’re not alone in our folly. Other animals, from birds to bees, make choices in the same way. Now, Tanya Latty and Madeleine Beekman from the University of Sydney, have found the same style of decision-making in a creature that’s completely unlike any of these animals – the slime mould, Physarum polycephalum. It’s a single-celled, amoeba-like creature that doesn’t have a brain.
Physarum spends most of its life as a large mat called a ‘plasmodium’, which is a single cell that contains many nuclei. The plasmodium searches for food by moving along like an amoeba and sending out a network of tendrils. Its search patterns are very sophisticated for a brainless organism. A Japanese group found that if they placed the mould among food sources arranged like Tokyo’s urban centres, it created a network that closely resembled Tokyo’s actual railway system. The slimy network was optimised to transport nutrients to the main plasmodium.
Scientists have long since discovered that you can run simple decision-making experiments with Physarum by presenting it with several food sources and seeing how it behaves. Typically, the plasmodium touches all the potential meals and then either ‘decides’ to move towards one, or splits itself among many.”
Read more at Discover
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I saw the title of this on Twitter, and assumed it was something to do with our Prime Minister
@Daniel Robinson: hahaha
if someone can afford to go to a restuarant they can easily afford a 25 pound bottle of wine but to some people 25 pounds is a weeks shopping
how’d you get that photo of my old boss?
sabermarris, it’s just an example. They could’ve used any situation that involves 3 options with one being the middle ground, such as the 3 sizes most fast food restaurants use for their drinks and chips. They happened to use the wine one. If you look beyond that, it’s really a fairly fascinating mechanism that they describe.
interesting but how is the way the mold chooses its food like the human choosing the middle of three options?
emergint: When they added another option (a ‘cheaper’ one, in this case, unlike in the example with the wine) to two other options (an ‘expensive’ one, that offered high nutrition at higher risk, and a ‘cheaper’ one that offered lower nutrition at no risk), the cheaper one suddenly became ‘middle ground’ (as the other option was similar, but lower-nutrition). This made the mold choose that one more often, even though the risk and nutritional value of this middle option remained the same.
It’s apparently fairly universal for living organisms to select the ‘middle ground’ when offered three options to compare, whereas two options make for different selection criteria.
Respect for the slime!