Utah's forest is actually one huge tree

Pando looks like a massive grove of Quaking Aspens, but if you could peel back the soil, you would find they are all connected to a single, massive heart. Every one of the 47,000 "trees" is actually a genetically identical clone growing from a massive underground root system that has been alive for at least 80,000 years.

This makes Pando the heaviest organism on the planet, weighing in at 13 million pounds. It is three times heavier than a Blue Whale. When one trunk dies, the root system simply sends up a new sprout nearby, making the organism effectively immortal as long as the roots remain healthy.

Because every trunk is part of the same individual, they all act in unison. In autumn, the entire 106-acre forest turns the exact same shade of yellow at the same time. They share water and nutrients through their veins, meaning a tree on a sunny ridge can keep a struggling tree in the shade alive by pumping sugar across the forest.

Scientists believe Pando hasn't successfully reproduced sexually using seeds for thousands of years. The climate has changed so much since it first sprouted that the conditions for seeds to take root no longer exist. It survives solely by cloning itself over and over again.

Today, the giant is shrinking. Mule deer are eating the new sprouts before they can turn into trunks, meaning the 80,000-year-old root system is slowly losing its ability to replace its aging parts.