There’s something odd about baboons – besides the obvious, of course.

When travelling any distance, a group of baboons travel in a very specific way.

Rather than in a herd as you might expect, or in a chaotic and individualistic manner, baboons travel single-file, in a straight line.

The reason for this formation – known as a ‘progression’ – has long been debated by scientists and animal behavior experts.

But now, thanks to a research team at Swansea University in the UK, the matter has finally been settled.

When it comes to other animals, structure in herd movement is important too, usually to protect weaker or younger members of the group.

In their study, the research team used GPS to track the movements of 78 baboon progressions over 36 days in total, testing a variety of hypothesis for the creatures’ specific formation.

And while their results, which were recently published in the journal Behavioral Ecology, prove that there is a distinct reason for the progression formations, they are far from the reasons that scientists have long speculated.

In fact, through their data the scientists learned that far from protecting the weak or following leaders, the progression was entirely dictated by the baboons’ friendships.

Known as the ‘social spandrel hypothesis’, the idea that baboons moved in order with their friends was by no means the most popular theory; and the researchers were as surprised as everyone else, as Swansea University’s Dr Andrew King confirmed in a statement:

“Surprisingly, the consistent order we see for the baboons we studied isn’t about avoiding danger like we see in prey animals when they position themselves in the middle of their social group, or for better access to food or water like we see in like we see in the movements of plains zebra. Instead, it’s driven by who they’re socially bonded with. They simply move with their friends, and this produces a consistent order.”

As one of the first truly understood examples of this behavior, the social spandrel challenges the ways in which we think about animals and the nature around us, as not entirely about life and death – about friendship and closeness too.

They just want to enjoy the journey with their pals, and who could blame them?

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