Evolution by variation and natural selection is often viewed as an 
optimization process that favors those organisms which are best 
adapted to their environment. This leaves open the issue of how to 
measure adaptation and what criterion is implied for optimization. 
This problem has been framed and analysed mathematically under the 
assumption that individuals compete to minimize expected losses 
across a series of decisions (e.g. choice of behavior), where each 
decision offers a stochastic payoff. But the fact that a particular 
analysis is tractable for a specified criterion does not imply the 
fidelity of that criterion. Computer simulations involving a 
version of the k-armed bandit problem can address the veracity of 
the hypothesis that individuals are selected to minmize expected 
losses. The results offered here do not support this hypothesis.