Plants Have Social Networks

Plants may be mostly stationary, but they have
meaningful conversations through the grapevine

Plants are so well connected, in fact, that they have both intranets, extranets and internets. Inside their own vessels, they communicate with proteins and RNA molecules from root to shoot (04/23/2010); outside, they have many social relationships with other organisms.  They even “friend” their partners, just like humans do on Facebook.

Ferris Jabr wrote about plant communication on New Scientist this week. “The botanical underground is a social network of powerful alliances and nepotism,” the article began. “Decoding its messages could lead to radical change in farms and forests.” Jabr wrote in terms of Darwinian competition, survival, antagonism, defense and kin selection, but the story is really about amazing mechanisms plants employ to communicate.

We’ve known for some time that plants respond to one another, but only now are we realising how subtle and sophisticated their interactions can be. Plants continually eavesdrop on each other’s chemical chatter – sometimes sympathetically, sometimes selfishly. Some plants, like the Scandinavian rhododendron, assist their neighbours by sharing resources. Others recognise close relatives and favour them over strangers. And at least one parasitic plant homes in on its host’s telltale chemical scent….

“Plants don’t go out to parties or to watch the movies, but they do have a social network,” says Suzanne Simard, a forest ecologist at the University of British Columbia in Vancouver, Canada. “They support each other and they fight with each other. The more we look at plant signalling and communication, the more we learn. It’s really incredible.”

Attributing selfishness or pugnacity to plants is, of course, an unjustified anthropomorphism. Without eyes, ears or brains, plants have uncanny abilities to send signals and respond to them. Some of these, Jabr described in the article, are volatile compounds wafted through the air. Even more amazing, though, are highways of fungal filaments in the soil that can relay messages and nutrients from plant to plant:

Beneath the forest floor, each spoonful of dirt contains millions of tiny organisms. These bacteria and fungi form a symbiotic relationship with plant roots, helping their hosts absorb water and vital elements like nitrogen in return for a steady supply of nutrients.

Now closer inspection has revealed that fungal threads physically unite the roots of dozens of trees, often of different species, into a single mycorrhizal network. These webs sprawled beneath our feet are genuine social networks.

Through these fungal highways, plants share not only nutrients, but information, Jabr said. “When a caterpillar starts to munch on a tomato plant, for example, the leaves produce noxious compounds that both repel the attacker and stimulate neighbouring plants to ready their own defences.” Plants recognize their own species and work together for the common good. But plants are also within communities of diverse organisms that benefit from each other’s contributions to the community.

We can’t yet speak the language of plants, but we know they speak through codes made of “soluble compounds including phenols, flavonoids, sugars, organic acids, amino acids and proteins, secreted by roots into the rhizosphere.” Even though “How these indicate relatedness is still a mystery,” a practical application would be for farmers to plant crops with the plants’ “friends” – “the strategic positioning of different crops or garden plants so they benefit one another by deterring pests, attracting pollinators and improving nutrient uptake.” In other words, instead of planting pesticide-drenched monoculture crops, they could go back to methods of Native Americans, who used such techniques for centuries.

Did these capabilities evolve slowly over millions of years?  Darwin’s “abominable mystery” – the emergence of flowering plants, the largest and most diverse group of plants on earth – was dealt another blow this week. Beautiful, detailed leaves that look like they were pressed in a book were found exquisitely preserved in the Jehol strata in China, reported New Scientist. Being dated at 123 million years old puts an advanced angiosperm “roughly contemporary with the ancestors of all flowering plants around today.”

Reporter Colin Barras claimed that “Flowering plants had an evolutionary edge over the conifers and other gymnosperms that were around at the time, and rapidly took over.” The problem with such explanations, though, is not the survival of the fittest, but the arrival of the fittest. Even assuming their own timeline, evolutionists have no explanation for how complex plants, communications networks and all, seemed to appear abruptly, fully formed, without ancestors.

Darwinism is the hacker in the social network, the malware among people just wanting to share good news.