The value of a strong brand is obvious. Less obvious is what it takes to create one. Decades of research point to two critical factors: brand salience – how well it comes to mind in a buying situation; and brand values – the core beliefs that it stands for. Less cited, but surely even more important, is brand trust, how much it is believed in.

Brand trust underpins both brand salience and brand values because a brand that isn’t trusted is worthless, no matter how salient it is or what its values are. And, while salience and values can be manipulated with effort and creativity, brand trust is notorious for being gained in drops and lost in buckets. Which is why brand managers often ask me what drives brand trust. To their surprise, my answer involves house finches, fiddler crabs, cuttlefish, peacocks, gazelles and elks.

In nature, trust is a precious commodity because it can be traded for reproductive rights. You may or may not have the genes that make you a good mate; what matters is that your potential mate trusts that you have. Consequently, many species fake it: house finches wear make-up; fiddler crabs grow fake claws; male cuttlefish signal attractiveness to females and harmlessness to males. The natural world is full of strategies akin to putting your old, airbrushed picture onto your dating profile. And, as evolution does, species develop counter-strategies to spot those whose signals of sexual attractiveness are insincere.

In 1975, Amotz Zahavi proposed the handicap principal. These are signals of sexual health and sexual attractiveness – peacocks’ tails, gazelles stotting (where they leap vertically into the air with all four legs held stiff and their back arched) and elk antlers are commonly cited examples – that are biologically costly. They persist not despite of the cost but because of it. Only high-quality mates can afford these costly signals, so they are more trustworthy than cheaper signals, like those of the made-up house finch. The cost also makes the signal hard to fake: a weak male with a huge tail or heavy antlers would be eaten or starved long before mating. And mates have learned to reward the most trustworthy signals with mating opportunities. Handicap theory, initially disputed, is now central to biologists’ explanations for these otherwise inexplicable traits. In short, their reproductive benefits outweigh the survival costs.

Not all marketers have read Zahavi’s work. When I see a consultancy pushing a ‘thought leadership’ white paper, I see a cheap, fake signal of authority that few would mistake for the more expensive signalling of a peer-reviewed paper or a substantial book. The same is true when I see the innumerable pharmaceutical brands that tout, with little evidence, their innovativeness or patient-centricity or value. Like fiddler crab claws, these are empty and weak attempts at deceit. And, of course, we see it most on CVs and LinkedIn pages, where personal branding rests on inflated titles and overstated responsibilities. All of these examples share signalling that is cheap and therefore, to potential partners, less trustworthy.

Probably more informative is the counter case of those who signal honestly. When companies like McKinsey or IQVIA publish weighty, relevant (but expensive to create) reports, they are stotting, just like a gazelle. When interview candidates open up that they’re not a details person, or they don’t have experience in the market, the cost of their admission signals believability. And pharma brand credibility? That’s the costliest of all. Honest, well-supported claims over many years, clear positioning that passes up on possible sales, reputable practices in dealing with opinion leaders and many other smaller practices around enquiries and complaints. Even when these activities are individually inexpensive, their aggregate cost is seen and recognised by the market. And it’s this complexity of signalling that make strong pharma brands hard to create and harder to compete with. It’s also why cheaper superficial activities can’t hope to build a strong brand when these expensive practices are neglected. As a seasoned marketer once told me, one can’t put lipstick on a pig.

So, as in many other aspect of our industry, evolution has some useful things to teach us about branding and, especially, brand trust. I include these lessons in my own workshops and there’s a good case for incorporating Zahavi into marketing textbooks. I’m not hopeful this would eliminate the house finches, fiddler crabs and cuttlefish of the marketing profession, but it might encourage the peacocks, gazelles and elk of our industry. Evolution rewards honest signals. Markets do too.