Shark Bay dolphins organise themselves into three different types of alliances.
The first is pairs or trios that work together to capture and herd fertile females. "These consortships can last over a month," Dr Connor explained.
In a "second-order alliance", the animals form "teams" of between four and 14 males which mount attacks on other groups to take their females, or to defend against attacks.
In a third level, the dolphins have "friendly relations" between these larger teams; they join forces to form larger dolphin armies, working together to defend their females against other large, aggressive groups.
Apparently, animals need to be "incredibly smart to operate in this type of society."
This post would exist without a tip from Bart Reynolds.