The discovery that some plants react to the presence of carnivores in their environment by altering their metabolic rate and increasing their root-system was counter-intuitive . But why should it have been? After all, where there are carnivores, there will be herbivores for them to eat, and a meat-eater with any sense won't wipe out its entire food supply. The plants have every reason to brace themselves for being nibbled by herbivores if there are carnivores out there.
Hmmm ... Plants and animals apparently observing, reasoning and acting accordingly? Research in Scotland has uncovered something else, pretty smart, going on in the under-world of plants.
Below ground there's a huge network of fungi whose thread-like strands exist in close association with plant roots. These fungi are already known to play an important role in the plants' mineral uptake, their tolerance to both root and shoot pathogens, and to water redistribution during drought stress; they're also known to facilitate seed establishment.
Now it has been shown that this fungal network can act as a plant-to-plant communication system, used to send signals to warn neighbours of a pest attack.
The fungal telegraph system can also, it seems, exert a positive or negative effect on neighbouring plants, and stimulate immune- and pest-defenses.
All these plants which are chatting to each other through their roots, and waving to their surroundings with their shoots, become our food.
Before our food can be incorporated into our tissues, however, it's processed in our gut.
Gut 'processing' involves mechanical and chemical digestion, but it also involves interaction with another whole living, interactive world: the gut microflora.
Our internal micro-ecosystem is highly dynamic, comprising around 1,000 different species of microbe and more than 7000 strains. Their actual profile varies not only with the individual but with time, diet, age, location and any disease state.
Our health is highly dependent of the health of our gut contents. Wider microflora influences include the stimulation of the immune system to release 'good' or 'bad' fermentation products, inter-bug competition or facilitation, and gut barrier functions. In particular, immune activation, and the generation of neuro-active metabolites by the gut microbes are being increasingly implicated in brain function change. Effects may impact on learning and memory, anxiety and depression, and well-being. Also see 
Interesting experiments which used probiotics to improve the profile of the gut microbes have indicated their role, for example, in stress reduction, reduced pain in IBS, and even temporary improvements in autism which is known to be associated with gut microflora idiosyncrasies.
In summary, we have living connections throughout our ecosystem above ground, below ground, and inside us which are total, intelligent, communicative, and necessary to maintain the whole in healthy balance.
Contrast this with our modern, conventional, mechanistic approach to agriculture with its carefully applied agri-chemical nutrients, chemical pesticides, hybrid crops and GM plants. Who would have linked all that dirt under the plants to the human brain?
For decades, conventional agriculture has applied microbiocidal, fungicidal, insecticidal and herbicidal chemicals at to every stage from soil preparation and the seed coatings, to the whole growing plant, and even post-harvest. The soil and plants in it are brain-dead.
The cocktail of chemicals in the crop is there to deal with pests which have taken hold there. The pests have taken hold because the agri-chemicals themselves have damaged the living systems, such as the microbial balance and fungal telegraph pest-alert in the soil, which would otherwise protect the plants. Being unable to respond to the natural world about them, the plants are dependent on agri-chemicals for protection. A self-fulfilling prophecy.
Most agri-chemicals affect microbes. Your gut microflora feeding off conventional food with its load of chemicals residues doesn't stand a chance. All the areas of your physical- and mental-health which are dependent on the gut microbes end up distorted beyond recognition.
In particular, glyphosate-based herbicides have been implicated in both soil and gut microbial disturbance [3,4,5]. When GM glyphosate-tolerant crops are sprayed, a huge proportion of the herbicide ends up in the soil and the rest is accumulated inside the crop. Glyphosate is also used in between plantings to prepare the soil especially in no-till agriculture, and immediately before harvesting to make the vegetation more manageable. Very soon, a whole array of GM crops which tolerate other problematic herbicidal chemicals are likely to come on stream .
Having seen the soil, your crops and your digestive system in this new, holistic, light, what do you say to the prospect of an orchestrated flooding of your food with novel microbes which never used to be there? See [6,7]
If your brain's beginning to hurt at the idea of this huge web of life all around you, tell the government to stop letting industry make holes in it.
 ARE PESTS NEEDED TO CONTROL CLIMATE CHANGE? - November 2013
 FOOD GENES INSIDE YOU - October 2013
 Prof. Don Huber warnings (GM Watch) - Glyphosate and GMOs impact on crops, soils, animals and man - Dr Don Huber
 ROUNDUP PROMOTES BOTULISM - June 2013
 GM REALITY CHECKS - December 2013
 N-FIX - TOO GOOD TO BE TRUE? - November 2013
 GENES ON THE MOVE - (Document link) GMFS Archive, December 2010
- Dr. Eva Sirinathsinghji, How Microbes Influence our Minds, Institute of Science in Society Report 20.11.13
- Dr. Eva Sirinathsinghji, Plants Warn One Another of Pest Attack through Mycorrhizal Fungal Network, Institute of Science in Society Report, 28.10.13