Despite what those ongoing US presidential primaries might lead one to think, a multi-disciplinary team of scientists finds that leadership is generally achieved as individuals gain experience -- in both humans and non-humans.

The experts from a wide range of disciplines examined patterns of leadership in a set of small-scale mammalian societies, including humans and other social mammals such as elephants and African mongoose.

The experts reviewed the evidence for leadership in four domains -- movement, food acquisition, within-group conflict mediation, and between-group interactions -- to categories patterns of leadership in five dimensions.

However, in some cases -- such as spotted hyenas and the Nootka, a Native Canadian tribe on the northwest coast of North America -- leadership is inherited rather than gained through experience, the study found.

"While previous work has typically started with the premise that leadership is somehow intrinsically different or more complex in humans than in other mammals, we started without a perceived notion about whether this should be the case," said Jennifer Smith from Mills College in Oakland, California.

In comparison to other mammal species, human leaders are not so powerful after all.

Leadership amongst other mammal species tends to be more concentrated, with leaders that wield more power over the group.

The similarities probably reflect shared cognitive mechanisms governing dominance and subordination, alliance formation, and decision-making as humans are mammals after all, Smith said.

The differences may be explained in part by humans' tendency to take on more specialized roles within society.

"Even in the least complex human societies, the scale of collective action is greater and presumably more critical for survival and reproduction than in most other mammalian societies," Smith said.

The study was published in the journal Trends in Ecology and Evolution.