QUOTE : Even environments in which organisms with superior information processing skills reap various rewards may not select for intelligence, because improvements to intelligence can (and often do) impose significant costs, such as higher energy consumption or slower maturation times, and those costs may outweigh whatever benefits are gained from smarter behavior. Excessively deadly environments also reduce the value of intelligence: the shorter one’s expected lifespan, the less time there will be for increased learning ability to pay off. Reduced selective pressure for intelligence slows the spread of intelligence-enhancing innovations, and thus the opportunity for selection to favor subsequent innovations that depend on them. Furthermore, evolution may wind up stuck in local optima that humans would notice and bypass by altering tradeoffs between exploitation and exploration or by providing a smooth progression of increasingly difficult intelligence tests.