This is how the story goes:

In 1952, on the tiny island of Kojima at the northern tip of Japan, a team of Japanese researchers is studying a colony of macaque monkeys.
A primary source of nutrition for the primates is sweet potatoes, found locally in the soil.
A young monkey, nicknamed Imo by the scientists, discovers that washing the vegetables in water before eating them reduces the acidic soil taste, and she proceeds to teach the rest of the colony.
Like any social contagion, the idea spreads organically from monkey to monkey, until, out of the blue, something remarkable happens – at a moment of critical mass in the number of monkeys taught to wash their potatoes (which is labeled here as 100 for ease of discussion) all the observed monkeys on the island begin washing their potatoes.
Even more astounding, researchers observe that monkeys on islands miles away also begin washing their potatoes, nearly simultaneously.
It’s amazing evidence for a previously unknown phenomenon of some kind of collective threshold model for unconscious enlightenment.
It’s also utter malarky.
This tale, and others very similar to it, have been making the rounds courtesy of self-styled empowerment gurus for half a century, A casual Google search will still turn up a great many who believe this thoroughly debunked story.

If the 100th monkey theory is false, why has it proved to be so popular? Even after the inventor of the story called it ‘a metaphor of my own making,’ the story continued to gain traction and now has hundreds of web pages dedicated to it.
The reality is that the spread of ideas is still as mysterious as ever. But while the instantaneous telepathic transfer of knowledge to primates is suspect, history is filled with multiple discovery events in scientific research.
In 1665, Isaac Newton began his work in England on fluxional calculus, primarily focused on the movement of physical bodies, but never published the work.
Nine years later, and 650 miles away, Gottfried Leibniz also invented a form of calculus, this one more focused on graphs.
Did the mystical cloud of knowledge touch both these men, like the monkeys were supposedly touched? Hardly.
The creation of calculus, the discovery of oxygen, the invention of radio and the battery, and even the theory of evolution -- these are just a few of the scientific and technological events that have had more than one founder simultaneously. If it’s not a telepathic hivemind at work, just what is it?
Prior to the 20th century, historians like Thomas Carlyle promoted the Great Men of History theory – the notion that certain individuals were touched by the divine and advanced human civilization by their God-given talents.
It’s no accident that as the concept of universal suffrage took root in nations affected by the Age of Enlightenment, a more egalitarian theory also developed – evolutionary epistemology.
Evolutionary epistemology states that a unit of knowledge (or ‘meme’, from Dawkin’s The Selfish Gene, 1978) performs in a similar manner to organisms in an evolutionary environment – that is, only those thoughts, designs, and combinations that are strong enough to survive in the marketplace of ideas will succeed.
From this perspective, then, it is not surprising that both Newton and Leibniz invented calculus independently. The time was ripe for calculus, and so calculus happened.
And it’s not a debate that’s really resolved by any means – Kevin Kelly is convinced it’s a matter of the network we’re plugged into, while Brian Eno calls someone who taps into the zeitgeist a scenius. And our culture is still filled with glowing magazine profiles of modern Imos who guide our world from on high.
Good ideas are often decades in the making, in the right environment, with the right people, at the right time. Perhaps the problem is that the prosaic methodology of knowledge advancement is too boring – no one wants to read a story about potatoes being washed unless it has a mystical ending.
Carl Jung wrote about the collective unconsciousness in hopeful terms – it is a romantic conception of the world, in opposition to one in which ideas live or die by their strengths alone.
The idea of a large invisible cloud of inherited thought staves off the permanence of death, links us to the past and future, and gives our memories shape and meaning. It is comforting.
We’ll just have to live, for now, with an imperfect facsimile.