The idea that selfishness and greed are drivers of evolution, and therefore possess underlying virtue, has been around for over a century, ever since Charles Darwin’s theory of evolution became widely accepted. The archetypal robber barons, Andrew Carnegie and John D. Rockefeller, both argued that the “survival of the fittest” principle justified their cutthroat tactics.
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In recent decades, researchers in evolutionary biology have overturned virtually every significant assumption in the selfish gene account. In its place, they have developed a far more sophisticated conception of how evolution works, revealing the rich tapestry of nature’s dynamic interconnectedness. Rather than evolution being driven by competition, it turns out that cooperation has played a far more important role.
In the early years of life on Earth, it’s likely that gene sharing (known officially as horizontal gene transfer) was the predominant way evolution worked. In fact, researchers now believe that the eukaryote genome was itself the result of a fusion of two prokaryotic genomes.
Instead of a Darwinian “tree of life,” biologists are offering alternative metaphors such as a “bush” or “net” of life to better describe how we are all intricately connected. In the memorable words of [biologist] Lynn Margulis: “Life did not take over the world by combat but by networking.”