The Largest Living Thing On Earth Is A Fungus

Blue whale is not a largest living thing on Earth. The actual largest living thing on the planet is a fungus. It is living in the Blue Mountains of Eastern Oregon, USA. This fungus is commonly known as ‘honey mushroom’. Its scientific name is Armillaria ostoyae. As like common mushrooms, it forms fruiting bodies in soil or on wood. It forms root-like structures (rhizomorphs) underground. The rhizomorphs of this ‘humungous fungus’ covers more than 3.4 square miles. This makes it a largest living organism. The rhizomorphs of this fungus are as thick as shoe lace and are used to find food. Armillaria infects commercially useful coniferous trees. The age of this fungus is estimated to be between 2,400 and 8,650 years.

(Armillaria 0stoyae - Wikimedia)

In 1980s, a group of scientists from Canada and USA reported about another humungous fungus from the same genus. They found Armillaria gallicain Upper Peninsula of Michigan, USA. This fungus spread over 37 hectares and weighed over 10⁵kg. At that time, they estimated its age as 1,500 years old. This fungus species is found in North America, Europe and Asia. The same scientists’ group revisited the site and reexamined the fungus. They have studied the growth rate of the fungus and determined that the fungus is 2,500 years old now. The weight of the fungus is also increased four times (4 x 10⁵kg) than the previous measurements. 

(Armillaria mellea - Wikimedia)

The scientists have collected 245 samples from the fungus. They extracted the DNA from the samples and sequenced them. The DNA sequences revealed that the samples were from the same individual fungus. They have also found that the rate of mutation in the fungus is ‘extremely low’. It indicates that they are well adopted to their environment. A. gallica fungus feeds on dead woods and also infects living trees. Since Armillaria fungi decompose the dead woods, they, along with the wood-decaying bacteria, are important for the environment.

(Armillaria gallica - Wikimedia)