What is the largest living organism? It’s bigger than an elephant, bigger than a blue whale, the largest organism on earth may not be what you expect. Introducing the biggest mushroom in the world, armillaria ostoyae or as it’s been fondly nicknamed, the Humongous Fungus. Covering 2,385 acres of Malheur National Forest, Oregon, it’s our largest organism, and from the way the fungus has been growing, it may also be our oldest organism. Humongous is estimated to be around 2,400 years – 8,650 years old.

Scientists have put together a comprehensive survey of past studies and verifiable documentation to determine the accurate size of a range of marine animals, from crabs to whales. They found that in many cases that the alleged record size for a species, like the giant squid, was significantly larger than anything that could be scientifically validated.

The largest animals to ever walk the Earth are, unsurprisingly, dinosaurs. Recently, a new species was discovered in Argentina in what is undoubtedly the biggest dinosaur excavation of all time. The team discovered that not only was this giant herbivore a new species but it was the largest dinosaur ever, dwarfing its closest competitors. The Titanosaur belongs to the group known as the sauropods and died approximately 101.6 million years ago. 

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The otherworldly creatures in the ocean's deepest depths
About 60 percent of the ocean is a cold, dark region that spans down to 11,000 meters. This zone is known as the deep ocean, and though it seems like an inhospitable and remote corner of the planet, it is actually one of the greatest habitats on Earth. Lidia Lins explores how so many species thrive in this mysterious underwater world.

What's hidden among the tallest trees on Earth?
When Stephen Sillett was a boy, he took to the forests of Pennsylvania with his brother and grandmother. Looking up into the dense branches and leaves, his curiosity was piqued: What was hidden up there? Wendell Oshiro tells the story of an adult Sillett’s bold (if not a little dangerous) exploration of the canopy of an ancient redwood and details some of the fascinating discoveries he made.