When faced with a stressful or dangerous situation, human beings have only two options, “fight” or “flight.” Right? Not if you’re a woman, says a new study. Looking at the ways men and women react to stress, researchers in Australia found that men tend to respond to stressful situations more aggressively than women do. “The aggressive fight-or-flight reaction is more dominant in men, while women predominantly adopt a less aggressive tend-and-befriend response,” Dr. Joohyung Lee, from the Prince Henry’s Insititute in Melbourne, said in a press release published on ScienceDaily. So while men favor punching or running away, women are more likely to try to diffuse a situation and seek out social support. The researchers suggested that this difference might all come down to one gene that only men have, called the SRY gene. The study, led by Lee and Professor Vincent Harley of Monash University, appeared in the journal BioEssays on March 8th. Previous research has shown that stressful situations activate the release of certain hormones into the body, which in turn trigger the fight-or-flight response. However, most of those studies focused solely on men, while Lee and Harley’s research looked at both men and women. The results suggest that the SRY gene impacts men’s hearts and brains during times of stress, causing blood pressure to rise and encouraging an aggressive fight-or-flight response, according to Marie Claire UK. Since the SRY gene is absent in women, these responses are instead guided by estrogen and other pain-controlling internal opiates, which don’t encourage aggression. Though the claims laid out by Lee and Harley are by no means certain, the researchers wrote that “SRY could have medical implications,” perhaps shedding light on certain disorders more prevalent in men, such as Parkinson’s Disease, schizophrenia, autism and ADHD, reported IBN Live.