FILTER BUBBLES

In last month's February 2nd issue of The Economist, bestowed on me by visiting tourists, in an article on Facebook the term "filter bubbles" was used. In the context of Facebook and other social media, filter bubbles occur when people see their preconceptions reinforced online. This may happen, for example, when websites provide ads and news based on the user's demographics or browsing history, or a person listens to news only from right- or left-leaning outlets.

I'm glad to have the term filter bubble for two reasons. First, nowadays Facebook-like filter bubbles pop up everywhere, and the filters used are sophisticated. When I had a Facebook page, though I never revealed where I was, how old or what sex I was, I saw plenty of ads for "beautiful Latin women seeking relationships with foreign men."

The second reason I'm glad to have the term is that in Nature many kinds of filter bubbles are profoundly important. Since humans are natural, and so is human thought, when filter bubbles occur among humans, they should be taken seriously. Here's how a certain kind of filter bubble might function in Nature:

Imagine a mountain range whose upper slopes are mantled with a certain wildflower species. As centuries pass, the region's climate grows more arid, so the mountain slopes on which the wildflower live constitute a filter bubble in which some measure of rainfall is being "filtered" out. From Nature's perspective, filter bubbles are parts of an ecosystem in which some expected, required feature is being limited. The wildflowers evolved expecting a certain amount of rainfall, and now that rainfall is diminishing.

The wildflower population survives by gradually shifting its numbers into the valley, where there's less drying-out exposure to wind and intense high-elevation sunlight. However, some individual wildflowers find refuge in the milder, moister microclimates at sheltered bases of large boulders, so they stay high up.

Over time, if the drying trend continues, the distance between the valley plants and those remaining by boulders high up becomes so great that pollinators no longer can transfer pollen between the two populations. The two populations became genetically isolated from one another. Gradually the two populations evolve along their own paths, each developing adaptations enhancing their chances for survival in their own environment, but not the other's -- for example, those above endure colder nights, shorter growing season, more UV radiation, etc. If this divergent evolution lasts long enough, the two populations develop into separate species.

So, filter bubbles, by introducing changes from the norm, cause stress in communities, often over time resulting in the communities' breakup. This happens whether among wildflowers, bacteria or humans.

Among humans, when a Facebook-type or news-outlet filter bubble gives the impression that a large percentage of people think or feel a certain way, it may or may not be true. Distortions of fact can be recognized by some people, but not by others. Today's false news inevitably produces two groups accusing one another of lying, and society is stressed and fragmented no less than if it were a wildflower population in a changing climate.

The false news filter bubble is a powerful tool for vested interests manipulating parts of society. If that bubble endures, like wildflowers with their diminishing rainfall, we humans with our growing confusion about who has the true facts may be headed toward our own special desert.