The InterAmerican highway runs from Alaska to eastern Panamá and then stops. There is no road between Panamá and Colombia, instead, only the virgin Darien rainforest. Unfortunately, conservation has little to do with the preservation of this rare jungle – we instead have to thank screw worms and cocaine.
A primary rainforest is more commonly known as "virgin" rainforest and signifies that the rainforest has never been significantly altered by humans and thus exists in its original condition. According to the United Nations Food and Agriculture Organization, only 36% of total forests are still primary forest and we're chopping that number down every year.
Fairly impressive then that Panamá has such a large, rare rainforest, huh? Believe me when I say that a culture of preservation has almost nothing to do with it.
Campesinos are agrarian country folk and cowboys that live everywhere in Panamá besides the capital. They've slowly spread, machete-first, through the Darien jungle towards Colombia and only stopped because the government won't let them continue. Your typical campesino calls uncut jungle sucio or "dirty." "Cleaning" it means chopping or burning it down. There's a joke here that says the best way to preserve the Darien forest is to kill two campesinos for every tree that we plant. So preservation culture clearly isn't a factor – the government is stopping them. But why?
There are two main reasons why we haven't cut a path through the jungle: 1. Plague and 2. the FARC. Foot and mouth disease has many negative effects on cattle, including extreme sickness, declined milk production and even death. Screw worms have similarly negative effects on livestock and both have been eradicated from the United States, so now the U.S. Department of Agriculture is actively against building a road through the Darien gap in order to avoid re-introduction of these plagues.
Trucks could also transport cocaine. The FARC are currently some of the only people in the world that frequent the Darien rainforest and they do so in order to move cocaine north. There are of course anti-narcotics police dedicated to the area, but those police are out-gunned and out of their element and the border thus remains de-facto FARC territory .
We're about 50 miles from fully connecting one of the highest inhabitable points of North America with the lowest point in South America, but instead we choose to conserve virgin rainforest because of a crop plague and a dangerous cocaine trade.
So save the rainforest and buy yourself a bag of cocaine!