Everybody, Trace here reporting for DNews. In late June a previously isolated tribe in Brazil walked out of the Amazon rainforest and peacefully approached a team of government scientists.

This was the first time in 20 years they'd done so!

The Brazilian Indian Affairs Department or FUNAI, said it wasn't a normal approach and they were worried.

They believe illegal logging forced these people from their ancestral homes.

There are humans all over this planet who still live like our ancient ancestors.

There may be 100 different isolated groups across the Amazon and New Guinea, on islands off the coast of India, and even in Malaysia and central Africa.

Even the most isolated made contact with OTHER tribes usually and some of those secondary tribes contact the local government regularly.

Not to mention, anthropologists attempt to photograph these people from the air, and missionaries attempt to evangelize on the ground -- so even if they don't understand what that giant metal bird is, they know other humans are around.

The largest isolated tribal area on earth is in South America.

The Peruvian and Brazilian governments have laws reserving land for these tribes to live on.

Brazil used to forcibly assimilate tribes, but now they have a policy of non-interference, similar to Star Trek's Prime Directive.

Which sounds great on paper, but most reserves end up being ravaged by illegal oil, logging, mining and drug-trafficking practices, driving the tribes away or killing them.

There are stories of tribes who fight back being killed in all sorts of gruesome ways.

Brazil has confirmed that 67 isolated tribes live in its territory, and Peru has 15 -- numbering more than 500 people overall.

The smallest known isolated tribe on our planet is difficult to pinpoint.

There are tribes of only a handful of individuals, down all the way to just one.

A man in his 40s living in the Brazilian state of Rondônia (HONduonia) is the last survivor of his tribe, the rest likely being killed by modern humans.

No one knows his name or his lost tribe.

In 2010, he was on the run from locals trying to chase him off his land so that they can develop it.

His huts were bulldozed, and he was alone. He killed an encroaching man by shooting an arrow into his chest. Yikes.

He's still out there somewhere.

The most isolated tribe in the world is a tough one to guess, but there are two known tribes on the Andaman Islands off the coast of India.

The most famous of the two are the Sentinelese who were described in 1290 by Marco Polo, as "a most violent and cruel generation."

They have no desire to join modern society.

They've fought off National Geographic and police helicopters with bows and arrows, and kill fisherman who land on their island.

Estimates say there may be as few as 40, but we can't get close enough to tell. There are probably more.

The dangers to these isolated tribes are many, and it's not just loggers with chainsaws or drug traffickers with guns.

In 1980, a mission trip from Florida set up camp in Colombia near the isolated Nukak tribe hoping to evangelize them.

Since these tribes are mainly living hunter-gatherer lifestyles, the missionaries brought metal tools to gain their trust.

But because of the Nukak's lack of immunity to modern viruses and bacteria, they brought axes, machetes and disease.

The Nukaks were stricken with respiratory infections and other diseases before being treated.

Most of them now live in poverty in a city near their old land.

A study in Nature of 238 indigenous populations in South America found declines averaged 43 percent after contact with outsiders.

Even simply contacting the tribes directly completely changes their chosen way of life.

A month after they came out to talk to the scientists, they emerged again.

This time they had the flu, which brings to mind a whole OTHER consideration.

Should we leave these people be? Or should we find a way to contact them?

We've got a comments section down below, so go use it.

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