The Web of Life (68) Plant Intelligence


Plant behaviour is active, purposeful, and intentional. The plant gathers information about its surroundings, combines this with internal information about its internal state and makes decisions that reconcile its well-being with its environment. ~ Anthony Trewavas

Intelligence is demonstrated by behaviors. Plants are so different from animals that is it commonly thought that plants do not behave at all.

Animals skitter about, bodies and limbs in motion, their communications in sounds, gestures, postures, and expressions. Chemical processes within proceed largely outside animal awareness and control. Decisions regularly take place unconsciously, only coming to awareness in their fruition.

In contrast, phenotypic plasticity and chemical production predominate plant behavior. Plant gestures and expressions are unrecognizable to us.

Plants use microfluidics and optics to move, change color, and pump water. ~ Greek American electrical engineer Demetri Psaltis

Visible plant actions largely comprise growing and discarding parts. Production and allocation of chemical resources is crucial plant behavior.

Plants intake and integrate information from among their various parts, combine it with remembered and genomically available knowledge, and intelligently make decisions. Because plant behavior is largely chemical and phenotypic, the number of choices that a plant at any moment has dwarfs any analogue of animal behavioral options.

Plants live a life of conscious chemistry. Their thoughts and behaviors are exercises of molecular awareness. The contrast to animals is incomparable.

The genomes of DNA-containing cell organelles (mitochondria, chloroplasts) can be laterally transmitted between organisms, a process known as organelle capture. Organelle capture occurs in plants. ~ Belgian biochemist Sandra Stegemann et al

As molecular mavens, plants comprehend the meaning of the informational codes behind genetics. They examine all the DNA that comes to them – whether bacterial, fungal, animal, or from another plant – to determine whether it may have value. This partly explains their ability to establish and regulate relations with other life forms.

Plants control their own genetic destiny: manipulating their genome in a vast variety of ways to achieve goals.

Part of identity is what you aren’t. Especially for plants because they are so changeable and susceptible to environmental conditions, the part of the genome that is not needed, or that might be providing exactly the wrong information, needs to be shut off reliably in each condition. This information is then passed on to daughter cells. ~ American microbiologist Doris Wagner

Deciding priorities and energy allocations is so complex that no plant behavior is autonomic. Unlike animals, there is no plant unconscious.

One aspect of existence that is the same for both plants and animals is memory. Plants remember their ecological interactions and derive meaning from them. Plants have long-term memory.

Animals process memories when they sleep. Plants rest during the night, but it is not known whether this helps them incorporate memories.

As with animals, the lessons that traumas may teach need to be learned, but the emotional impact of traumas must be set aside if a plant is to recover and lead a healthy life.

Stress memories may be maladaptive, hindering recovery and affecting development and potential yield. In some circumstances, it may be advantageous for plants to learn to forget. ~ Australian botanist Peter Crisp et al

Animal emotions play critical roles in memory retention, judgment, and motivation. Evidence of plant emotions is anecdotal, but the evolutionary advantage of emotions is such that it is hard to imagine that plants lack emotive feelings. Plants demonstrable will to live suggests there being an emotional context to their behaviors.

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Plants plan. Decisions about growth or defense are processes of potentiality, aimed at meeting anticipated needs.

Plants anticipate attacks from insects in much the same way that they anticipate the sunrise. ~ American biologist Michael Covington

Assessing the far-red radiation coming off the leaves of competitors, plants can predict potential loss of light in the foreseeable future. One intentional response is shade avoidance – a goal-oriented behavior.

There is an extensive spread of prerain green-up over Africa. ~ Nigerian terrestrial ecologist Tracy Adole et al

A swath of Sub-Saharan Africa has a rainy season with an attendant bloom of vegetation. Plants there anticipate rain coming and green up before the rain arrives. They also know when the rainy season ends and lose their lushness just after the rain stops, thereby conserving their resources.

Associative learning is an essential plant behaviour. ~ Australian biologist Monica Gagliano et al

Experience and calculation of relative gain determine decisions in plants just as they do in animals. Plants constantly assess the probabilities of favorable outcomes given an ample array of possibilities for root and shoot growth vis-à-vis defensive measures. Plants take risks when they feel they need to.

Competition plays a fundamental role in plant ecology. Plants evolved both the ability to detect the presence of neighbours and to plastically adjust their phenotypes in response. Plants can respond to light competition in 3 strategies, comprising vertical growth, which promotes competitive dominance; shade tolerance, which maximises performance under shade; or lateral growth, which offers avoidance of competition. Plants choose according to outcome. Plants adopt optimal scenarios. ~ German botanist Michal Gruntman et al