New research shows that morning sickness might be due to the broad diet of humans, according to Live Science. No other mammal has shown morning sickness, and "if morning sickness was the byproduct of conflict between mother and embryo or fetus," as previously thought, "one might expect other mammals to have it too." Scientists at UC Boulder suggest that morning sickness could be triggered by "the sight, smell, or taste of meats and strong-tasting vegetables, which were historically likely to contain foodborne microbes or birth-defect-inducing chemicals [and] alcohol and cigarette smoke." Much more work needs to be done to determine the way morning sickness really works and the scientific reasons for its widespread nature in humans. [Live Science]