Most of us, when we imagine a plant, visualize it sitting there, growing, waiting around to be pollinated, or even eaten. But did you know that the bunchberry dogwood can move faster than a speeding bullet and tomatoes can summon wasps when they sense they are being eaten by a caterpillar? And that is just the tip of the iceberg. Plants can communicate with one another, outsmart mammals, and start forest fires!Plants are truly wondrous. They provide us with food, oxygen, shelter, beauty, and much more. In this fast paced world, their true magic, may sometimes get overlooked.
1. The Bat Seducer
Come in, please (Image: Ralph Mangelsdorff and Ralph Simon)
First up in this magnificent mix of Viridiplantae is a flower hailing out of the Cuban rain forests, Marcgravia evenia. Like Gotham City has the ‘Bat Signal,’ so too does this beautiful flower. A scientist by the name of Ralph Simon noticed the peculiar leaf shape of this plant and suspected that it might be an adaptation.
A study was conducted, using a loudspeaker-microphone combination, Simon and colleagues played sounds at the plant and analyzed the resulting echoes. They found striking differences between the acoustic properties of disc-shaped leaves and the flatter ordinary leaves.
Ordinary leaves produced a strong echo when face-on to the loudspeaker-microphone, but the signal strength dropped – and its acoustic signature changed – as the loudspeaker-microphone swung round to a position edge-on to the leaf. The signal from a disc-shaped leaf remained strong and characteristic no matter where the loudspeaker-microphone was placed within an 80-degree arc in front of the leaf.
To test the theory that this disc-shaped leaf was specifically evolved to guide bats into the flower, Simon trained three male nectar-feeding bats (Glossophaga soricina) to search for a feeder 2.5 centimetres wide – roughly the same size as a single nectary – in a chamber filled with artificial foliage.
The results showed that the bats found the feeder 50 percent faster when a replica of the disc-shaped leaf was placed above it. The ordinary leaf replica showed no difference in search times.
That’s right, the Marcgravia evenia actually evolved specially adapted echoing transmitter leaves that serve to guide bats into the flower of the plant! It is no coincidence that the Marcgravia evenia depends solely on the bat to disperse its seed.
2. Dodder Vine, The Cunning Hunter
Credit: Justin Runyon/De Moraes and Mescher Labs
Next up is the cunning dodder vine, a weed that can ‘sniff out’ its victims. The dodder is a parasitic plant that cannot survive on its own. It cannot produce food through photosynthesis, and doesn’t even grow roots. It must find a host as soon as it sprouts or it will die.
Scientists found that this parasitic weed can sense airborne chemicals released by nearby plants and seek them out.
According to Live Science, scientists had thought the parasitic plant used a hit-or-miss tactic, and any hook-up was the result of a chance encounter.
But a lab experiment found 80 percent of the dodders grew toward a tomato plant. And when they tried to trick the dodder with artificial tomato plants and pots of moist dirt, the dodder didn’t take the bait. Its shoots didn’t grow in any particular direction.
In an even more impressive feat, the dodders could distinguish between a good host plant, such as the tomato, and a poor one such as wheat. When placed in the middle of wheat and tomato plants, the dodders swayed above ground in circular movements in the direction of the tomato plants. Considering the latest revelations about the negative health effects of wheat, that is one smart plant.
3. The Flower that is Faster than a Speeding Bullet
Credit: D. Whitaker, M. Laskowski, A. Acosta, J. Edwards.
The bunchberry dogwood is one of the fastest movers in the entire animal kingdom. Found in forests from the East coast of the US all the way to Canada, this ‘super speeder’ moves 100 times faster than a Venus flytrap, and over twice as fasts as the famous, ultra-fast striking mantis shrimp.
The bunchberry dogwood, spreads its pollen in a catapult-like manner at incredible speed in less than 0.5 milliseconds.
Using high-speed video observations, Joan Edwards and her colleagues at Edwards of Williams College, timed the tiny explosions of Cornus Canadensis, the bunchberry dogwood.
The results, the dogwoods petals restrain the pollen-holding stamens in a folded position. When the petals flip open, the four stamens unfurl – accelerating at 2,400 times the force of gravity, or about 800 times what an astronaut might experience during liftoff.
These amazing flowers bloom in a shorter time than it takes a fired bullet to reach the end of the rifle barrel! How’s that for fast?
4. The Unforgiving Fig
Fig trees are completely reliant upon tiny wasps for pollination. Fig wasps are the sole pollinators of fig trees, they can breed nowhere else other than inside the fig. The wasp pollinates the fig by burrowing inside figs as this is the plant’s flower turned outside in. This is a classic example of mutualism, where neither of the parties can survive without the other.
But what happens to the freeloaders? Sometimes, a wasp will use the fig for room and board but not actually pollenate the fig. The fig tree “punishes” these “cheaters” by prematurely dropping the unpollinated fruit, killing the wasp’s offspring inside! That’s right, the tree will abort the offspring of the freeloader wasps!
According to a study conducted by researchers working at the Smithsonian Tropical Research Institute this punishment may be critical to maintaining the relationship between the wasp and the fig.
“Relationships require give and take. We want to know what forces maintain this 80-million-year-old arrangement between figs and their wasp pollinators.” said lead author, Charlotte Jandér, graduate student in Cornell University’s Department of Neurobiology and Behavior, who conducted the study as a Smithsonian pre-doctoral fellow. “What prevents the wasps from reaping the benefits of the relationship without paying the costs?”
The fig wins the award for nature’s strictest landlord.
5. Eucalyptus Trees, Natures Arsonists.
Eucalyptus trees have evolved a particularly devious tactic in which to eliminate their competition in the forest.
Eucalypts slowly cast their leaf litter and branches on the forest floor over time. Eventually this litter accumulates and waits patiently for a spark of some sort. Eucalyptus oil is highly flammable, so much so that some trees have even been known to explode!
Eucalyptus trees encourage fires because they are resistant to them when their competition is not. Eucalypts obtain long-term fire survivability from their ability to regenerate from epicormic buds situated deep within their thick bark, or from lignotubers, or by producing serotinous fruits.
Eucalypts are the John Orr’s of the forest and while that can be good for them, sometimes it can lead to catastrophic firestorms. In fact the Oakland firestorm of 1991 that destroyed thousands of homes was attributed in part to a forest of non-native eucalyptus trees.
So the question is, if a Eucalyptus tree secretly plots to scorch the forest and no one is around to hear it, does it make a sound?
6. Tomato the ‘Wasp Whisperer’
From Wikimedia Commons
Upon a brief observation one may make the assumption that plants are but passive victims of the predators that choose to feed on them. However this is not the case with the tomato.
According to a study conducted by UC Davis, when the tomato is attacked by insects, it launches an immune-like chemical defense which can summon beneficial insects.
In this UC Davis study of tomato plants, Jennifer Thaler, a UC Davis postdoctoral fellow, found that wasps on tomato plants whose defense systems had been artificially stimulated killed twice as many caterpillars as did wasps on untreated plants.
How’s that for plant defense? “You wanna eat me caterpillar? Say hello to my little friends!”
7. The Socializers, Plants Can Communicate
Scientists are finding traits in plants that show them capable of having behaviors once thought to be unique to animals. While research into plant behavior is still somewhat new, some of the findings are paradigm shattering.
A paper published in the American Journal of Botany, describes how Impatiens pallida, a common flowering plant, devotes less energy than usual to growing roots when surrounded by relatives. In the presence of genetically unrelated Impatiens, individuals grow their roots as fast as they can.
This is typical in the animal world, known as kin recognition, in which animals help their family members and not just themselves. The idea that plants can communicate, however, has long been taboo. However, to further support this idea of plant kin recognition, a paper was published that showed how American searocket plants accelerated their root growth when placed in pots of strangers, but slowed it down when potted with siblings. Were they animals, they’d be described as sharing water and food.
So while these plants aren’t actually talking, they are emitting a sort of chemical signal which allows them to adjust behavior based on the genetic code of their surrounding plants. It is positively mind blowing to ponder this ability.