Evolution is a trial and error process that leads to a species' characteristics best adapted to its environment to be preserved throughout generations. When it comes to social connections, studies show that the most connected among us are also the less lonely (duh), the happiest (mm) and the most likely to find a job thanks to the power of what Granovetter calls "weak ties". So, why aren't we all that connected ? If it's such a great feature, why didn't our evolution make us all the same way : Popular, connected, at the center of our networks ?
Well because being connected is not all bright and shiny. At least not all the time. That is because the most connected individuals, with the most friends and a central place in the network, are also the ones most prone to be hit by a disease when it starts spreading. It is possible that our most connected ancestors are also the ones who were hit most often by diseases and it is possible that this is the very reason that didn't allow the "connector's" gene to spread unto all of us. The "connectors" simply did not survive.
“Traits that are always adaptive tend to reach what geneticists call fixation in the population: in the long run, everyone becomes the same. But when there are conflicting pressures—under some circumstances, a trait is beneficial, but under others, it is not—then it is possible to maintain diversity in the population in the face of natural selection” says Nicholas Christakis. This "connector" gene did not spread because it was a conflicting characteristic that did not enhance the odds of survival invariably.
When it comes to business, marketing, the financial markets, imagine you're a hub, a central nod, as in the pic below, through which everything the network produces ends up transiting : You'll be the first to know when interesting news starts spreading but you're also the first one who'll get to hear about a false rumor.
Whether this is an interesting position to be in then depends on what position you're in. You want to be at the center of that network when you're looking for a job but you want to keep your distance when you're trading stocks. A trader will typically keep an eye on the center of the network (normally guys who buy into every fad, whose mood, decisions and process change every two days), see how it's working out for them at a given time and react accordingly.
You might then think that it's never good to be too far, right ? Wrong. Imagine you're a trader now and this network represents the owners of Mortgage Backed Securities in 2006 ... Sometimes, you want to be at the outskirts of a system. Imagine this network up there is New York City. You don't want to live in the very center of NYC if you want to give your lungs a chance for a better future. You would very much like to live in some quiet suburb.
Positioning oneself in a network is hence vital for survival and that is the gene, the characteristic, that lived on through the generations. Our abilities to choose which and how many friends to have, who and how many persons to deal with in different situations. Darwin, aka evolution (but the title sounded better that way) does have something to do with who your friends are.