There are many studies of gender differences in EI, but to sum them up, women on average tend to have better emotional intelligence scores than men -- but this is only on average, and there's conflicting data on this.
A caveat: when you're talking about gender differences in the behavioral domain you’re speaking about largely overlapping bell curves of ability. For example, one ability women consistently show an advantage in is emotional empathy – but this does not mean that a given man can't be as emotionally empathic as the most empathic woman. The abilities that tend to be greater in men often have to do with emotional self-mastery – but, again, this does not mean that a woman can't be as emotionally self-regulated as the most balanced man. It’s just when you're talking about statistical differences that the group trends show up.
The neuroscientist Tania Singer has new brain data that informs these trends. She was looking at two emotional systems, one for cognitive empathy and another for emotional empathy. Singer says that women tend to be more highly developed in the mirror neuron system, and so rely on it more than men do for signals of empathy. Men, in contrast, tend to have a burst of the mirror neuron system and then go into a problem-solving mode.
There's another way of looking at male-female differences in EI. This is the work of Simon Baron-Cohen at Cambridge University, who says that there's an extreme “female brain” which has lots of mirror neuron activity and is high in emotional empathy – but not so good at systems analysis. By contrast, the extreme “male brain“ excels in systems thinking and is poor at emotional empathy30. These brain types are at the far extremes of a Bell curve, with most of us somewhere in the middle. However, he does not mean that all men have the “male brain”, nor all women the “female brain.” Many women are adept at systems thinking, and many men excellent at emotional empathy.
My colleague Ruth Malloy of the Hay Group in Boston has looked at gender differences on the Emotional and Social Competence Inventory (which I co-designed). Her analysis revealed that while in general you find gender differences among the various competencies, when you only look at the pool of star performers (people in the top ten percent of business performance) those differences wash out. The men are as good as the women, the women as good as the men, across the board.
That reminds me of an observation made by Frans de Waal, a scientist who studies primate behavior at the Yerkes National Primate Center in Atlanta. He’s found that when a chimp sees another chimp in distress – either from an injury or a loss of social status – the first chimp mimics the behavior of the distressed chimp, a primal form of empathy. Many chimps will then go over and give some solace to the upset chimp, for example, stroking it to help it calm down. Female chimps offer this kind of solace more often than male chimps do – with one intriguing exception: the alpha males, who are the troupe leaders, give solace even more often than do female chimps. One of the basic functions of a leader, it seems, is to offer appropriate emotional support.