Scientists were always confused about how competitive plants are when sharing a space with other plants.
After multiple contrasting studies, the recent one has solved some doubts for us all. We are always told that humans are the most selfish species on the planet, but are we? There are many instances of humans being selfish and not considering what may happen to the other species and even their own. But it may be consoling to know that we aren’t the only ones who are the most competitive and selfish. It looks like the good ol’ plants aren’t so good after all.
Plants Compete For Space
Researchers have always wondered for several years have ever wondered and tried to understand the competition between plants. Still, the results have always been juxtaposed about plant competition in the botanical world. However, one study has caught the eyes of many as they could have found out about plants’ battle.
To put the study in easier words, imagine yourself as a cute plant, with lovely flowers, ready to bear fruits and leaves are as green as emeralds, all sturdily tall in soil. But there’s a problem, there is another cute plant quite close to you, standing tall on the same ground. You both need the same amount of water and nutrients from the soil. How will you procure it without facing any malnourishment?
Multiple studies with different results have spun the heads of many researchers for years. A study reveals that plants do have some competition based on a model which the plants in a real simulated world ideally would follow. These were the initial tests. Like any other part of the plant, it takes energy and nutrients to grow roots and keep them healthy. Plants also extract more nutrients from the soil as compared to utilizing them. Plants can detect the amount of water and mineral levels in the ground, act accordingly, and spread their roots.
Contentious 'Behavior' of Plants- Game Theory
If a plant is an alone dweller in the region, it will utilize the minerals to the best of its advantage and thrive without putting in extra efforts to cultivate the nutrients. But when it shares the region with other fellow plants, the equation changes. This is simple enough. Interestingly, scientists helped the study by using the apparatus from the game theory.
Game theory is the detailed analysis of models based on diplomatic interactions and enhances decision-making among rational decision-makers. Yes, it sounds like only avid gamers may use this theory, but it is quite widespread in economics, computer sciences, and even life sciences. This study was published about two weeks ago in ScienceMag.
A study published in 2001 postulated that plants that grow close together in a given area result in a “tragedy of the commons.” This essentially means that each plant will try to branch out further, thus increasing its spatial distribution. However, these plants end up extracting lesser nutrients than expected. This has also been observed in real-world experiments where plants sharing their spaces had a more extensive root mass than plants that grow alone.
Now you may think, well, that’s the end, isn’t it? We can declare that plants are selfish now, right? Well no. Remember how we mentioned previously that the studies were juxtapositioned? This what we exactly meant.
What Does A Plant's Competitiveness Mean?
Some studies have found the results to be the complete opposite. They revealed that plants sharing a space did not grow out many roots and increase their root mass. Other studies saw no difference between plants that grew alone and plants growing with other neighboring plants.
Ciro Cabal, a Ph.D. student in ecology and evolutionary biology at Princeton University who is also the lead author of the recent study, said, “There was all this controversy.” He thought, what if the model he and his team made and the other previous models had some critical elements missing? Despite all the plant roots having an equal treatment, it was still observed that the distance of the roots growing away from the stem of the plant had to spend more energy and nutrients to ensure that they’re healthy.
Cabal and his co-authors constructed a new model. “We incorporated space, and we found this new theory,” he said. However, in this model, the plants outsmarted us all. Plants competing with other plants will grow less of the far distanced roots, therefore, saving energy, but will flourish their root system, which is closer to the plant stem. This not only conserves their life and gives them enough nutrition but also prevents its roots from getting tangled with other plant root systems while sneakily extracting all the nutrients for themselves.
Now that’s what we term as a pro gamer move!
Give Us Space!
So the answer was space. Not only us, but even plants need their own space. According to Cabal, “Whether plants with neighbors over-or underproduce roots in comparison with solo plants relies on how far distant are the two competing plants. So those results from previous studies that seemed to contradict each other are “all possible according to our model.”
Now, the researchers tested out this model in the real world. A bunch of sweet papers was planted in different circumstances. Some of the plants were grown alone, and some were raised in pairs with a distance of 2-4 inches between them. The roots of the paired plants were stained in different colors as compared to their chlorophyll competitor.
After a few months, the researchers mapped out the spatial distribution off the roots and observed that the real world plants exactly followed their mathematical model. The origins of the paired plants were denser towards the stems and more sparse the more it grew away from the plant compared to the single plants.
According to Jochen Schenk, a professor of plant biology at the California State University Fullerton who wasn’t part of the study said, it “provides a reliable baseline probability for how root systems might act in the presence of neighbors. It brings together hypotheses and findings that previously seemed contradictory.”
But he did caution that the results shouldn’t be overgeneralized. “I would not accept the assertions that a single test with one plant species can predict what plants will generally do,” he said.
Distinctive Spatial Adaptation
There is a possibility that different species will respond in different ways when faced with competition. Latest studies also indicate that organisms like fungi and microbes also play a role in how some plants will interact below the ground. Even Cabal himself hadn’t expected those results. “I truly believe that the conclusions we present are true,” he said. He plans to experiments with the same model on a few species of Mediterranean shrub.
If this strategy seems to be used by many plants, it can be used in several aspects of agriculture. The competitive trait could be slowly weeded out with breeding, which will lead to an increase in healthier agricultural yields. So, in the end, yes, plants are a little sneaky when it comes to sharing nutrients, but it’s not yet enough to take the spot of humans. It could be comforting, or terrifying, to know that we still may be the most selfish creatures on Earth.