With Valentine’s Day coming up, lots of us are preoccupied with finding a partner. Aside from receiving flowers and an attractive personality, one trait that people often look for in a relationship is good communication. People are not alone in this quest. In fact, many organisms also look to communicate with each other, although it may look a bit different. There are many mutually beneficial relationships in the world of animals, plants and microorganisms.
For example, bioluminescent bacteria (V. fischeri) can live inside of squid (Euprymna scolopes) to help them glow and evade predators and hide from prey. In this mutualistic symbiotic relationship, colonization of the bacteria triggers developmental events in the squid through the release of the correct sugars and amino acids. They quite literally grow up and spend the rest of their lives together. How romantic!
Another common, somewhat risqué natural relationship is bacterial conjugation, also known as “bacteria sex” (or the subject of my IS). In this process, a bacteria senses a specific chemical inhabitant (like an antibiotic or cleaning solution) and will not survive unless it has a certain resistance gene to that compound. If the gene is present on one microorganism but not another, it will reach a segment of its filament out and pass the genetic information onto the other. This allows both organisms to serve in the inhibitory conditions. In certain conditions, they cannot live without each other. < 3
However, my favorite example of relationships in nature comes not from ocean animals or my own IS, but from plants. Even seemingly solitary trees in forests form partnerships among themselves and the bacteria at their roots. According to a research article by Dr. Suzzanne Simard, professor at the University of British Columbia, trees form partnerships in many ways. Chemical signals from one tree can be interpreted by another to warn them of danger. Tree roots and fungi can form a partnership, known as mycorrhizae, in which the fungi envelopes and fuses with the tree roots to help them extract water and nutrients. This can supply the trees with up to 40% of their nitrogen supplies and allows trees to share between 10-40% of the carbon stored in their roots. A true give and take relationship!
The roots are a communication method within themselves. Stress signals upon the changing of leaves can transfer stress signals to nearby trees and cause them to increase and speed up their production of defensive enzymes. This may sound crazy, so how do we know that trees are in constant communication? Dr. Simard sent radioactive carbon molecules to one tree, caused distress (by putt a cloth over) a neighboring tree so it was shaded from the sun and then waited to see if the radioactive carbon would show up in the neighboring tree. It did. Through these back and forth conversations, trees can help each other out and increase the resilience of the whole community, much like a kindhearted neighbor loaning you some sugar. Given how long trees are around and how frequently and altruistically they communicate with each other, it makes the hope of a long and happy partnership seem more and more possible.
For more information on talking trees, go to this TED Talk: https://www.ted.com/talks/suzanne_simard_how_trees_talk_to_each_other?language=en