Prepubescent Mice Shed Tears To Fend Off Adults' Romantic Advances
Two Week Old Mouse ShwSie via Wikimedia Commons Unlike humans, mice don't have laws or social customs to govern who they mate with. Nor can a mouse ask a potential partner about her age. So how do mice know that their potential mate is acceptably adult? Through tears, according to a study led by Harvard Medical School. A certain pheromone called the exocrine-gland secreting peptide 22, or ESP22, is only found in the tears of juvenile mice, around 2 or 3 weeks old, the researchers observed, and stops being released after around 4 weeks, when the mouse reaches puberty. This chemical signal allows other mice to recognize that a young mouse is not quite mature enough to get frisky with. "These findings provide a molecular framework for understanding how a sensory system can regulate behaviour," the authors write. They found ESP22 activated...