was how football fans greeted Rio Ferdinand

when he was banned for missing a drugs test.

Some football chants are made up on the spot,

some have echoed around the same grounds for generations.

But scientists think they are a practice

that has deep roots in human culture.

Every social group ever studied, from the Maori Hakka

to the Sufi Whirling Dervishes

to awkward British people at a wedding,

engages in some form of group singing, dancing, and chanting.

Why is this?

Psychologists have found

that when a group of people engage in collective behaviour -

like chanting -

it has a profound effect on how they think and feel.

Group singing's been shown to have a powerful effect

on the mood of depressed people.

As well as the uplifting music,

it seems that synchronising your breathing,

heartrate and voice with other people

has the remarkable effect of making us feel connected to one another.

But of course football fans don't usually feel connected

to everyone in the stadium.

There are plenty of examples of football chants that are rude,

offensive, even racist or homophobic.

Though they've historically been a means to abuse players

and referees,

they can also endorse more positive values

like celebrating striker Mo Salah's goals with,

♪If he scores another few then I'll be Muslim, too♪

Collective behaviour like chanting is, more than anything,

a way to express social identity and the values of that group.

Like the Liverpool fans chanting, "Justice for the 96"

in support of the Hillsborough disaster victims.

Chanting at a football match doesn't just bond a group together

in love and harmony,

there is a dark side to coordinated behaviour.

Most armies around the world march up and down in parades.

For the past 100 years,

at least since the invention of the machine gun,

it's been a bad idea to walk slowly towards the enemy in a straight line.

So why do soldiers march and chant together?

In one experiment,

people were asked to put a jar of live woodlice into a grinder.

The people who had marched in unison around the car park beforehand

threw about 50% more of the bugs into the grinder

than those who had walked the same distance

but not in a coordinated march.

Please note there was actually an escape chute in the grinder

and every bug escaped unharmed.

This suggests coordinated behaviours

can lower people's sense of personal autonomy,

and make them more likely to be obedient to aggressive action.

And there is a final reason that people might chant

at a football match.

Writing has only been around for a few thousand years,

but we find chants and songs in every pre-literate culture.

Even today in India,

it's the chanted version of Vedic texts

that's seen as the definitive version, not the written form.

Perhaps chanting is a call back to those older practises of encoding

and sharing cultural knowledge.

So next time you hear a thousand people yelling...

to the referee,

remember that it's because they're bonding with each other,

affirming their social identity

and using an ancient technology to record knowledge.

And, perhaps, because the referee doesn't know what he's doing.

Thanks for watching! :)

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