This Wild Yam Tricks Birds With Fake Berries to Survive

A Chinese scientist bent down to collect what looked like plump, shiny berries in 2019, only to discover nature had just played a brilliant trick on him.

Ecological biologist Gao Chen had stumbled upon the black-bulb yam, a climbing vine that produces fake berries so convincing they fool both scientists and birds. These aren't fruits at all but bulbils, tiny clones the plant uses to reproduce since it lost the ability to make seeds millions of years ago.

Most plants that reproduce this way simply drop their clones at their feet, forcing parent and offspring to compete for the same soil and sunlight. The black-bulb yam found a better solution: make your clones look delicious.

Chen and his team at the Chinese Academy of Sciences spent three years studying this evolutionary workaround. They compared the fake berries to real ones from 27 nearby plant species and found something remarkable. To bird eyes, the yam's bulbils are nearly identical to actual berries in size, color and shine.

The researchers set up cameras to catch the deception in action. While most visiting birds ignored the fake berries when real fruit was plentiful, 22 different bird species eventually took the bait when food became scarce. The brown-breasted bulbul, a small songbird common in Southeast Asia, turned out to be one of the yam's most reliable transportation services.

The best part? The birds get zero nutritional benefit from eating these bulbils, yet the fake berries pass through their digestive systems in about 30 minutes, emerging intact and ready to sprout. Based on flight patterns, some bulbils could travel nearly half a mile before being deposited in their new homes, far from competing with their parent plants.

The Bright Side: The black-bulb yam isn't alone in its clever tactics. Dozens of tropical plants produce "mimetic seeds" wrapped in fruit-like coatings that look tasty but offer little nutrition. The marble berry and common peony both use similar strategies. Some plants go even further: the silver arrowreed produces seeds that look and smell like antelope droppings, tricking dung beetles into burying them in perfect growing conditions.

This discovery shows how creative evolution can be when survival is on the line. A plant that lost its ability to make seeds didn't give up; it adapted, creating an entirely new strategy that benefits from the appetites of unsuspecting birds.

Nature's ingenuity continues to surprise us in the most delightful ways.