Plants are intelligent problem solvers that know how to adapt

Goldenrod can detect nearby plants by sensing far-red light ratios reflected off leaves, allowing it to adapt its responses to herbivores based on its surroundings. According to a new study led by Cornell University, this adaptability might indicate plant intelligence, if intelligence is defined as solving problems based on environmental information. 

Goldenrod, for example, emits chemicals to repel pests and signals neighboring plants to activate their defenses. Thus, plants may function as superorganisms, with each cell contributing to overall intelligence without central coordination.

Information processing among intelligent plants 

“There are more than 70 definitions that are published for intelligence and there is no agreement on what it is, even within a given field,” said lead author Andre Kessler, a chemical ecologist at Cornell.  

Many people think intelligence needs a central nervous system that uses electrical signals to process information. Some plant biologists liken plant vascular systems to central nervous systems, suggesting plants have a centralized entity for information processing and response. However, Kessler disagrees with this notion.

“There is no good evidence for any of the homologies with the nervous system, even though we clearly see electrical signaling in plants, but the question is how important is that signaling for a plant’s ability to process environmental cues?” he said.

Plants can change their own behavior 

To argue for plant intelligence, Kessler and his doctoral student Michael Mueller defined it simply as “the ability to solve problems, based on the information that you get from the environment, toward a particular goal.”

Kessler’s earlier research demonstrated that goldenrod emits volatile organic compounds (VOCs) to signal neighboring plants when attacked by herbivores, prompting them to produce their own defenses. This response changes depending on the presence of nearby plants, indicating that goldenrod adapts its behavior based on environmental cues. 

“Depending on the information it receives from the environment, the plant changes its standard behavior,” Kessler explained. This ability to predict the future presence of herbivores and act accordingly is a key aspect of what the authors describe as plant intelligence.

Decentralized model of plant intelligence 

Furthermore, Kessler is intrigued by the idea proposed by mathematicians in the 1920s, suggesting plants function more like beehives, where each cell operates independently but contributes to a collective response. “The brain in the plant is the entire plant without the need of central coordination,” he said. 

Plants use chemical signaling, rather than electrical, to communicate and trigger collective responses. This decentralized model of intelligence emphasizes the sophisticated sensory capabilities of individual plant cells, which can detect specific volatile compounds and light spectra to coordinate their behavior.

According to the experts, considering plants as intelligent entities can generate new hypotheses about their chemical communication mechanisms and broaden our understanding of intelligence itself. This perspective is particularly relevant in the context of artificial intelligence, as it challenges traditional notions of problem-solving and goal-oriented behavior.

What makes plants intelligent?

The concept of plant intelligence revolves around the idea that plants exhibit complex behaviors and responses to their environment that resemble intelligent actions. Here are several factors that contribute to this notion:

Communication 

Plants can communicate with each other through chemical signals. For example, when a plant is attacked by herbivores, it can release chemicals that warn nearby plants of the danger, prompting them to produce defensive compounds.

Memory

Some plants have been shown to remember and learn from past experiences. For instance, the Mimosa pudica plant, known for its rapid leaf folding response to touch, can learn to ignore harmless stimuli over time.

Problem-solving 

Plants can adapt to changing conditions and optimize resource use. Their roots can navigate through the soil to find water and nutrients, and they can adjust their growth patterns to maximize light exposure.

Sensing and responding

Plants have sophisticated sensory systems that detect changes in their environment, such as light, gravity, water, and chemical signals. They can then alter their growth and development in response to these stimuli.

Symbiotic relationships 

Plants engage in mutually beneficial relationships with other organisms, such as mycorrhizal fungi, which help them absorb nutrients, or nitrogen-fixing bacteria in their roots.

Complex behavior

Plants exhibit behaviors that can be considered complex, such as opening and closing flowers, orienting leaves and stems toward light, and even moving leaves to capture insects in carnivorous plants.

The study is published in the journal Plant Signaling & Behavior.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–