Traders on Wall Street show how institutions can take big risksSpencer Platt/Getty ImagesThe Gambling AnimalGlenn Harrison and Don Ross (Profile Books)Insights into animal evolution used to come from studying a creatures evolutionary relationships to its closest relatives. To lampoon this slightly: we once saw humans as a kind of chimp. Our perspectives widened and, looking across ecosystems, we began to see what drives animals who share the same environment towards similar survival solutions. This is convergent evolution the process by which, say, if you are a vertebrate living in an aqueous medium, you are almost certainly going to end up looking