Birds with high levels of stress hormones mate more and provide better care for their offspring, according to a new study from Queen's University (Canada). "We tend to think that having high levels of glucocorticoid, a hormone linked to stress, indicates that an individual has fewer options to find a mate, but in the bicolor swallow ( Tachycineta bicolor ) the opposite occurs", explains Frances Boiner, co-author of the study published in the next issue of the journal Biology Letters .
In their experiments, Boiner and his colleagues found that females with the largest clutch produced twice as much stress hormone . In addition, the increase in this hormone made the birds feed their young in the nest more quickly than the rest. In conclusion, stress favors parental behavior in birds, says Boiner.
