We already know that men and women tend to have very different drinking habits throughout their lives. But, as NPR reports, new research suggests our income levels can play a role here, too. For the study, published online this week in Alcoholism: Clinical and Experimental Research, researchers interviewed 672 pairs of twins. Participants were asked about their socioeconomic status (SES), which included their household income and education level, as well as their alcohol consumption patterns. The results showed that people with more money tended to drink more overall. But, participants in the low-SES group showed way more variability in their drinking patterns than those in the high-SES group. The more affluent group was more likely to keep their alcohol intake both moderate and consistent. The fact that participants were twins (some fraternal and some identical) also allowed researchers to look at the involvement of genetics in their drinking patterns. Because the high-income participants were all consistent in their alcohol habits, the authors suggest that the low-SES group's environmental stressors may be triggering already-present genetic vulnarabilities to excessive drinking — and that having extra cash and all that it affords may protect the high-SES group from that excess. However, other research suggests that being able to drink alcohol represents an evolutionary advantage humans developed about 10 million years ago, when people certainly weren't making the big bucks. So, we'll accept the skills evolution has handed us, and drink to that.