Darwin theorized that peacocks’ colorful plumage was a sign of        their evolutionary strength.

Wall Street has always been known as a cutthroat kind of place, but lately it seems big investment banks are just mulling around, hoping their competitors die first.

A report on Friday by Goldman Sachs bank analysts said that the industry has entered what they called a state of “reverse Darwinism,” in which banks are betting their long-suffering trading operations can increase revenue not by stealing business from rivals on a competitive basis, but by waiting for rivals to call it quits – leaving their clients with no choice but to move business elsewhere.

The Goldman analysts met with senior executives from Citigroup, Bank of America, Morgan Stanley and Lazard to find out what’s going on in their apparently stagnant capital markets businesses. The executives’ tone was “universally lackluster,” according to the analysts, who predict that investment banking and trading revenues will once again drop about 20 percent this quarter, as they did in the year-ago period. More pain is expected ahead as new derivatives trading rules, higher capital requirements and the long-awaited Volcker rule are implemented.

With that bleak backdrop, everyone is trying to figure out where they can cut costs and what businesses even make sense to stay in anymore. The only way to make money in trading, it seems, is to have such huge market share that enormous volumes can make up for the cost of the operation.