I recently wrote about male dolphins who remember other males who did not come to their aid when they needed it. They bore a grudge against these individuals to the point where they wouldn’t help them, indicating sophisticated behaviour. The same team of researchers also found that dolphins form alliances to bully females into mating.
Dolphins appear to be carefree but when it comes to courtship they are very purposeful, committed and fiercely competitive. They found that the dolphins of Shark Bay, Western Australia, which they studied for 40 years, exhibit complex social systems including alliances between male dolphins to cooperate in catching a female as a partner.
In fact, each male dolphin forms a lifelong friendship or pact with one or two males. They cooperate to increase their chances of procreation. When they meet a female who is ready to mate, this coalition of males surround her and usher her away from competing males. The researchers believe that they are intimidating and impressing females.
They also perform acrobatic displays around the female, in unison, once again to impress. If the female tries to break away it is said that they are quite likely to bite and charge at her. It’s important to keep the female because they give birth to one calf about every five years. A coalition of males may have to fend off competing males for a month before one of them has a chance to mate.
These coalitions, as I have called them, are called “first-order alliances”. They will also try and steal females from other alliances. They even call for backup help sometimes. These alliances of two or three males exist within an umbrella group of up to 14 males banding together to form a tribe, which is called a “second-order alliance”.
The purpose once again of the second-order alliance is to get females. And sometimes second-order alliances band together to create a third tier with the same purpose in mind. They say that dolphins are the only creatures other than humans where one group has solicited a second to confront a third. Not even chimpanzees do this, although they do form gangs to attack rival camps.
And in order to figure out which males they can rely on in these alliances, the males keep a score of who they can depend upon. And this takes me full circle to the first sentence about how males can bear a grudge against other males who do not come to their assistance when required.