FOR ZEBRA FINCHES, singing love songs—rather than listening to them—can induce euphoria. A study published recently in the online scientific journal PLoS ONE finds that when a male finch serenades a potential mate, neurons in his brain are activated in much the same way as a human brain under the influence of drugs such as cocaine. In humans, cocaine triggers the release of dopamine, which creates a feeling of reward and causes the brain to crave more of that sensation. Among finches, males apparently find the feeling of singing to a possible mate similarly addictive, a definite plus for reproduction. Interestingly, the study’s authors did not find similar stimulation when the males sing alone—only when their songs were directed at a female.