Most humans believe they are the most intelligent and conscious beings on Earth. But what if that idea is completely wrong? A growing number of scientists are now suggesting that plants may actually be conscious — and, since there are more than three trillion trees on our planet alone, we could be wildly outnumbered!
Plant neurobiologist Stefano Mancuso has found some truly exciting evidence. First, when plants are given anesthesia — the same drug used to put humans to sleep before surgery — they stop responding, just as we do. Second, Mancuso placed a bean plant about one metre from a metal rod in his laboratory. In a time-lapse video, the plant sent out a long hooked shoot that swung back and forth until it caught the rod. The plant clearly "knew" the rod was there. In another experiment, two bean plants were growing toward the same support pole. When one plant reached it first, the second plant immediately sensed this and began searching for a different support. Mancuso called this behaviour a demonstration of consciousness.
His colleague Monica Gagliano studied mimosa plants — famous for folding their leaves when touched. She repeatedly dropped mimosas in a basket. At first, the plants closed their leaves every time. But after many drops, they stopped reacting, apparently learning that the experience was harmless. Weeks later, they still did not react, showing that plants can remember.
There is also a remarkable story from South Africa. Kudu antelopes were mysteriously dying on a game reserve. Zoologist Wouter Van Hoven discovered that acacia trees had poisoned them. When the kudu overgrazed the trees, the acacias increased tannins in their leaves to protect themselves. Even more astonishingly, they sent a chemical warning signal up to 50 metres away so that neighbouring trees could do the same.
In 2025, Mancuso co-authored research suggesting that plants have two levels of thinking — a fast, automatic level and a slower, more deliberate one, similar to the unconscious and conscious minds of humans.
Perhaps it is time to rethink our place in nature. If plants are conscious, the implications are enormous — not just for science, but for how we understand life itself.