"The difference between the irrational investor and the shark on the beach is the shorter length of time the investor has had to adapt to the financial environment, and the much faster speed with which that environment is changing. 

"Economic expansions and contractions are the consequences of individuals and institutions adapting to changing financial environments, and bubbles and crashes are the result when the change occurs too quickly. 

"In the 1992 election, Democratic strategist James Carville prioritized matters succinctly for Clinton campaigners: “The economy, stupid!” I hope to convince you that biologists should be reminding economists, “It’s the environment, stupid!”

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"From the biological perspective, the limitations of Homo economicus are now obvious.  Neuroscience and evolutionary biology confirm that rational expectations and the Efficient Markets Hypothesis capture only a portion of the full range of human behavior."