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As a SciShow viewer, you can  keep building your STEM skills with 20% off an annual premium  subscription at Brilliant.org/SciShow. [♪ INTRO] When it comes to plant biology, it seems like we should have most of it figured out by now. Sure, we spot a new species or maybe a  funky adaptation every once in a while, but for the most part, it doesn’t seem like there can be all that much  more to discover, right?

Wrong! There is a vining plant  called Boquila trifoliolata that is challenging everything we  know about how plants work, and even raises a pretty bizarre  question: Can plants see? This unassuming climbing vine is  found in the temperate rainforests of Chile and Argentina, where it seamlessly  blends in with its surrounding plants.

In fact, it blends in with  its floral neighbors so well because it literally changes  its leaves to copy them. Boquila can alter almost every aspect of  its leaves, including the size, shape, color, orientation, and  stalk length, all in order to disguise itself like the  trees it grows on for support. This may be an adaptation to avoid predation by both climbing on another leafy plant  and blending in with its host leaves, which might be less tasty to bugs, slugs,  and snails than Boquila leaves are.

Boquila vines have been found to mimic the leaves of more than a dozen species of trees.   And, they don’t stop at just mimicking  the plants they’re climbing on! They can copy other nearby plants  too, without even touching them. Not only that, but they can even grow  multiple leaf shapes on a single vine, meaning they can mimic more  than just one plant at a time.

And the kicker is that scientists still don’t know how these plants are able to do any of it. They do have a couple of ideas, though. One fascinating hypothesis is that the  vines are receiving the genetic blueprint to make these new shapes directly  from those neighboring leaves.

This neat trick is known as  horizontal gene transfer, or the process of passing genetic  material directly from one mature organism to another, as opposed to a parent  giving their offspring their genes. Horizontal gene transfer is pretty  common between single celled organisms like bacteria, which pass around genes  for things like antibiotic resistance; stuff that keeps the whole population healthy. And we also know that genes can  be transferred between members of different species, even in  multicellular organisms.

For example, scientists have previously  discovered that genes have “jumped” between rice and another type of grain  called millet, despite the fact that those two species diverged between  30 and 60 million years ago. But exactly how horizontal gene  transfer works in plants is still a bit of a head scratcher, and has  been considered an unlikely mechanism for something as complex and  sophisticated as rapid mimicry. For a little bit of context, gene  transfer changing a plant’s appearance would be like a handshake changing  your eye color, or someone sneezing on you making your hair curly.

It just, it feels… a little out there. But in 2021, some of the same  researchers that originally described the shape-shifting properties  of Boquila vines came up with a plausible mechanism for  these plants swapping genes. Their idea is that airborne  bacteria carry genetic material from the neighboring plants to Boquila’s leaves, and the leaves can then integrate that information into their own genes and use it to change shape.

This is wild, but it outlines  how strange of a problem it is. So, to test this, they sequenced the  DNA in bacteria from Boquila leaves as well as the leaves from plants it had copied. When they compared the bacterial communities, they found an overlap between  Boquila and the mimicked plants.

Not only that, but there were significant  differences between the bacteria on the Boquila leaves that had changed  shape and the Boquila that hadn’t. These results hint that bacteria may  be playing a role in the exchange of genetic material, which would be a pretty  revolutionary idea, botanically speaking. That said, the authors also acknowledge that more has to be done to lock down this hypothesis.

It’s a pretty extraordinary claim; it  would need pretty extraordinary evidence. But there is another even wilder possibility for how Boquila has become a master of disguise. A recent study has explored the rather  controversial idea that these vines can see.

The science-fiction-y idea that  plants might be able to see has been around since 1905. That’s when Austrian botanist  Gottlieb Haberlandt suggested that the outer layer of cells on a leaf could  act as a lens, focusing the rays of light onto light-sensing cells, which  all together is called an ocellus. We have found some forms of  photoreceptors in plants, but whether they allow plants to  actually see shapes or colors, or even exist at all, has yet to be confirmed.

But that hasn’t stopped researchers from exploring the idea of plant vision in Boquila. In a 2022 study, researchers decided to  give some Boquila plants an eye exam. Since they knew that Boquila  can mimic living plants, they decided to see if the vines  could copy fake, plastic plants too.

Since a plastic plant doesn’t  have any genes to transfer, it would mean that if Boquila  was able to mimic these leaves, it was not doing so by using genetics  or any chemical signals from the host. They also grew other vines below a shelf, blocking their line of sight to the fake plants. As the Boquila vine grew  toward the artificial plant, its leaves started to morph, reportedly  becoming more like the fake leaves, while the Boquila branches hidden by the  shelf got bigger, but didn’t change shape.

All of which, the authors argue,  supports their idea that Boquila can see. Now to be clear, other plant  biologists are pretty skeptical of the plant vision hypothesis, going  as far to call the idea “far-fetched”. Not only that, but several researchers have  criticized the design of that 2022 study, saying the variables that  can influence leaf shape, like the age of the leaves and light  exposure, weren’t properly controlled for.

They also criticized the lack of  explanation for how plant vision could reasonably work, since the  whole hypothesis hinges on the plants, like, actually being able to see stuff. But the study’s authors stand by their work, and are currently doing more  experiments with Boquila plants to further investigate their  plant vision hypothesis. And even the critics will  concede that they won’t say it’s impossible that plants can see.

We might even find that both  horizontal gene transfer and plant vision are at play when  these guys mimic their neighbors. These weird copycats are just one more example of how little we really understand  about the natural world! ‘Cause who knows? Maybe when you look at that houseplant  on your desk, it’s looking back at you.

Regardless of how they do it,  you have to admit that it is pretty cool these plants can shape-shift. They’re 3D objects that change  into different shaped 3D objects! And if that doesn’t immediately send  you reeling, then you can always watch this video again after  taking the Brilliant course on 3D .

Brilliant is an online learning  platform with courses in science, computer science, and math. And this particular course uses  interactive puzzles and lessons to help you appreciate just how  complicated the third dimension is. From cross sections to folding, you will learn how 3D shapes can bend themselves and your mind.

And since you watch SciShow, you  can get 20% off an annual premium Brilliant subscription by clicking  the link in the description down below or by going to Brilliant.org/SciShow. Thanks to you for watching and thanks to Brilliant for supporting this SciShow video! [♪ OUTRO]