But the packs multiplied and multiplied.

They need to be part of the pack.

The boys climbed up the tree faster than a pack of squirrels.

And when you build those three rules in, automatically you start to see swarms that look very much like fish schools or bird flocks.

Some theorists try to explain this with an alpha male theory of leadership.

Learning became reinforced. Bands of apes ventured into the open.

Another thing that has to be true about this pack this pack cannot be really materialistic.

People used to get together in flocks, Bohemians liked one thing, the simple people, something else.

The key to being part of a hunting pack is the word pack.

It's a spectacular sight to see a flock of white doves take off into the sky, looking like a flash of festive fireworks.

Poverty runs rampant, orphanages overflow with abandoned children, countless packs of wild dogs roam the streets.

I'll show you a computer model made by Iain Couzin, a researcher at Oxford, that shows how swarms work.

You can't be a pissed off pack. You can't be bearing grudges, like, I'm not chasing that guy's antelope.

We often hear about a pack of stray dogs attacking people, but we practically never hear about why this is happening.

When you're small and vulnerable, like these starlings, or like the fish, it helps to swarm to avoid predators, to confuse predators.

One can copy movements and motor acts without understanding their meaning. This happens when a flock of geese suddenly takes flight from a lake, blindly following the flock's first frightened member.

After a jogger was scratched and bitten by a pack of stray dogs on December 14, 2011, at a new park in Punggol in Singapore, the Agri Food Veterinary Authority (AVA) has stepped up efforts to round up the stray dogs around the area.

During that time, though, they emerge in huge numbers in some regions and may take up to 300 ml of blood per day from each animal in a caribou herd.

Animal welfare advocates protest that crowding the chickens keeps them from forming a natural flock, causes them stress, and, in the case of laying hens, prevents them from even stretching their wings. The air in the sheds is high in ammonia from bird feces, which are usually allowed to pile up for months and in some cases for a year or more before being cleaned out.

Animal welfare advocates protest that crowding the chickens keeps them from forming a natural flock, causes them stress, and, in the case of laying hens, prevents them from even stretching their wings.

Mathematician Steven Strogatz shows how flocks of creatures manage to synchronize and act as a unit when no one's giving orders. The powerful tendency extends into the realm of objects, too.

Now, when you think of a coral reef, this is what most people think of all these big, hard, elaborate corals and lots of bright, colorful fishes and things.

The idea that one must somehow supplant one's mentor, cast the previous generation out into the wilderness, and make oneself the leader of the pack seems to obsess men.

Now, to get into that, let me begin with what might have occurred to you immediately when you hear that we're talking about synchrony in nature, which is the glorious example of birds that flock together, or fish swimming in organized schools.