The 'Savanna' Hypothesis Of Online Design
I’m currently reading a fascinating paper titled “Evolved Responses to Landscapes” by Gordon Orians and Judith Heerwagen that was written back in 1992. The objective was to see if humans have an evolved preference for an ideal habitat. The researchers called their hunch the Savanna Hypothesis, noting that because homo sapiens spent much of our evolutionary history on the plains of tropical Africa, we should have a natural affinity for this type of landscape.
Your typical savanna features some cover from vegetation and trees, but not too much, which would allow natural predators to advance unnoticed. The environment should offer enough lushness to indicate the presence of ample food and water. It should allow for easy mobility. And it should be visually intriguing, encouraging us to venture and explore our habitat.
Here’s a quote from the paper: “Landscapes that aid and encourage exploration, wayfinding and information processing should be more favored than landscapes that impede these needs.”
The researchers, after showing participants hundreds of pictures of different landscapes, found significant support for their hypothesis. Most of us have a preference for landscapes that resemble our evolutionary origin. And the younger we are, the more predictable the preference. With age, we tend to adapt to where we live and develop a preference for it.
In reading this study, I couldn’t help but equate it to Pirolli and Card’s Information Foraging Theory. The two PARC researchers said that the strategies we use to hunt for information in a hyperlinked digital format (such as a webpage) seem to correspond to evolved optimal foraging strategies used by many species, including humans back in our hunting and foraging days. If, as Pirolli and Card theorized, we borrow inherent strategies for foraging and adapt them for new purposes, like looking for information, why wouldn’t we also apply evolved environmental preferences to new experiences, like the design of a Web page?
Consider the description of an ideal habitat quoted above. We want to be able to quickly determine our navigation options, with just a teaser of things still to explore. We want open space, so we can quickly survey our options, but we also want the promise of abundant rewards, either in the form of food and sustenance -- or, in the online case, information and utility. After all, what is a website but another environment to navigate?
I find the idea of creating a home page design that incorporates a liberal dose of intrigue and promise particularly compelling. In a physical space, such an invitation may take the form of a road or pathway curving behind some trees or over a gentle rise. Who can resist such an invitation to explore just a little further?
Why should we take the same approach with a home page or landing page? Orians and Heerwagen explain that we tend to “way-find” through new environments in three distinct stages: First, we quickly scan the environment to decide if it’s even worth exploring. Do we stay here or move on to another, more hospitable location? This very quick scan really frames all the interactions to take place after it. After this “go-no/go” scan, we then start surveying the environment to gather information and find the most promising path to take. The final phase -- true engagement with our surroundings -- is when we decide to stay put and get some things done.
Coincidentally (or not?), I have found users take a very similar approach to evaluating a webpage. We’ve even entrenched this behavior into a usability best practice we call the “3 Scan Rule.” The first scan is to determine the promise of the page. Is it visually appealing? Is it relevant? Is it user-friendly? All these questions should be able to be answered in one second or less. In fact, a study at Carleton University found that we can reliably judge the aesthetic appeal of a website in as short a span as 50 milliseconds. That’s less time than it takes to blink your eye.
The second scan is to determine the best path. This typically involves exploring the primary navigation options, scanning graphics and headings and quickly looking at bullet lists to determine how “rich” the page is. Is it relevant to our intent? Does it look like there’s sufficient content for us to invest our time? Are there compelling navigation options that offer us more? This scan should take no more than 10 seconds.
Finally, there’s the in-depth scan. It’s here where we more deeply engage with the content. This can take anywhere from several seconds to several minutes.
At this point, the connection between the inherently pleasing characteristics of the African savanna and a well-designed website is no more than a hypothesis on my part. But I have to admit: I find the concept intriguing, like a half-obscured pathway disappearing over a swell on the horizon, waiting to be explored.