Do you know that mushrooms can "bleed"? The bleeding tooth fungus (Hydnellum peckii) can amazingly ooze out red fluid as if it had been pricked with a needle, but this is actually caused by a process similar to water seeping out at the edges of a plant's leaves.

When the soil surrounding the fungus is too wet, the bleeding tooth fungus will have excess water inside, which creates pressure to force the water to "bleed out." Although scientists don't know what this gooey fluid is, they infer that its red color comes from a pigment found in the fungus. 

Interestingly, this "bleeding" phenomenon only happens when the bleeding tooth fungus is still young and growing. When it matures, it loses the red sap on the top and becomes rather dull in appearance. So, every "bleeding" mushroom you find is an adolescent. People even call it "strawberries and cream," but you surely don't want to have a bowl of it. By the way, it is not toxic despite its sinister look. 

You might wonder why it is called "tooth" fungus because it doesn't always look like a molar. Well, it gets the name for the tooth-like spines beneath the "bleeding" cap, where its spores are produced. 

If you want to find the bleeding tooth fungus in the forest, you'd better look for coniferous trees first. The fungus develops a symbiotic relationship with coniferous trees. In other words, the tree provides carbon dioxide to the fungus, while the fungus helps the tree better absorb amino acids and minerals in the soil. Its presence often indicates that the forest is rich in biodiversity. 

The bleeding tooth fungus surprisingly has many potential uses. People often dry it and make it into a beige dye. It can also create blue-green hues when combined with substances like alum or iron. Besides, scientists have discovered that the fungus contains anti-coagulant substances that can keep blood clots from forming and thelophoric acid, which may be used in the treatment of Alzheimer's disease in the future.

About 'Alien Fungi'

What is the most ancient land-based life after bacteria? Fungi! An industrious decomposer in the natural world, fungi have existed for almost a billion years, at least 500 million years older than the first land plants. In the series "Alien Fungi," CGTN explores some peculiar-looking fungi with alien features and observes how they enjoy their eternal, cryptic lives on damp floors, decaying wood and hidden areas.

Read more:

Octopus stinkhorn: 'Octopus' in the woods

Turkey tail mushrooms: The medicinal 'swirling clouds'

Common puffball: The pear-shaped fungi that release gas

Stag's horn fungus

Dead man's fingers

Porcelain fungi: Glistening translucent beauties

Cup fungi: The little cups

Ink caps: The mushrooms with dripping ink

Coral mushroom: The corals of the land

Do you dare to eat these violet mushrooms?

Death cap: The deadly fungi with a harmless look

Fly agaric: The mushroom that inspired 'Alice in Wonderland' creators

Bioluminescent fungi: The mushrooms that glow in the dark

Bridal veil stinkhorn: A girlish mushroom that loves to wear 'skirt'

Bird's nest fungi: Dandelion-like drifting life

Barometer Earthstar: The fallen star praying for moisture

(All images via Getty)

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